HomeMy WebLinkAboutR21-541336
RESOLUTION NO. R21-541
A RESOLUTION ADOPTING THE CITY OF PLAINVIEW LONG RANGE
WATER SUPPLY PLAN
WHEREAS, the City of Plainview is a home -rule municipality and a political
subdivision of the State of Texas duly organized and operating under the laws of the State
of Texas; and
WHEREAS, the City of Plainview provides water to the public for wholesale,
commercial and residential use with the source of such water coming from water
purchased and delivered to the City by the Canadian River Municipal Water Authority and
supplemented with water from the Ogallala Aquifer pumped by wells owned by the City
of Plainview; and
WHEREAS, in 2020, the City Council of the City of Plainview directed City staff to
develop a plan to provide adequate water supplies to meet the future water supply needs
of wholesale, commercial and residential water customers to ensure the long-term
viability of meeting the City's water needs; and
WHEREAS, to that end, in 2020, the City of Plainview commissioned HDR
Engineering, Inc. to develop a Long -Range Water Supply Plan to guide the City in meeting
future water supply needs with the following objectives:
(i) provide sufficient annual supply volume to meet the City's needs;
(ii) provide sufficient capacity to meet projected maximum daily water demands;
and
(iii) promote conservation and education; and
WHEREAS, the attached Long -Range Water Supply Plan developed by HDR
Engineering, Inc., provides a roadmap for the City to meet the future water supply needs
of the City's water customers, including meeting the objectives outlined above, detailing
projections of future water supply demands through 2070, evaluating the capability of the
City's current water supply system to meet those projected demands, and evaluating
several water supply strategies to address projected future shortages.
NOW THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF
PLAINVIEW THAT:
1. The recitals and findings outlined above are approved, adopted and
incorporated herein as though set forth fully herein.
2. The attached Long -Range Water Supply Plan developed by HDR
Engineering, Inc., is hereby accepted and adopted by the City Council and the City
Resolution R21-541 Page 1 of 2
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Manager of the City of Plainview or his designee is hereby authorized to develop
strategies and/or programs for City Council consideration to meet the objectives and
goals as outlined in such plan.
Approved by the City Council this 14th day of December, 2021.
CITY OF PLAINVIEW, TEXAS
(A/ UP. If I,.
Charles Sfarne4 Mayor
ATTEST:
&JJLA,01
Belinda Hinojosa, City e etary
Resolution R21-541 Page 2 of 2
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Long -Range Water Supply Plan
Prepared for:
PLAINVIEW,TX
explore the opportuntttes
City of Plainview, Texas
Prepared by:
HDR Engineering, Inc.
TBPE Firm No. F-754
December 1, 2021
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Contents
ExecutiveSummary
......................................................................................................................1
1 Introduction
..........................................................................................................................5
1.1
Purpose and Scope.....................................................................................................5
2 Water Demand Projections..................................................................................................
5
2.1
Current Water Use......................................................................................................
5
2.2
Future Water Demands...............................................................................................8
2.2.1 Annual Water Demands..................................................................................
9
2.2.2 Maximum -Day Water Demands....................................................................12
2.2.3 Effects of Demand Reduction Assumptions..................................................15
2.2.4 Population Projections Inferred from Growth in Residential
Connections..................................................................................................
16
3 Current
Water Supplies......................................................................................................
18
3.1
CRMWA Supplies.....................................................................................................18
3.2
City -Owned Groundwater Supplies...........................................................................19
3.3
Potential Reclaimed Water Supplies.........................................................................
20
3.4
Overall Water Supply Reliability................................................................................
21
3.4.1 Annual Supplies............................................................................................
21
4 Future
3.4.2 Maximum -Day Supplies................................................................................
Water Supply Needs...............................................................................................
22
22
4.1
Annual Supply Needs................................................................................................22
4.2
Maximum -Day Needs................................................................................................24
5 Evaluations
of Strategies to Meet Needs...........................................................................
26
5.1
Water Conservation..................................................................................................
28
5.1.1 Strategy Description......................................................................................
28
5.1.2 Adopted Best Management Practices...........................................................
29
5.1.3 Estimated Costs............................................................................................
30
5.2
Additional Groundwater Development......................................................................
32
5.2.1 Additional City -Developed Groundwater from the Ogallala Aquifer ..............
32
5.2.2 Additional City -Developed Groundwater from the Dockum Aquifer ..............
32
5.2.3 Optimization of the City's Current Wellfield...................................................36
5.3
Additional CRMWA Supplies.....................................................................................38
5.3.1 Strategy Description......................................................................................
38
5.3.2 Water Availability...........................................................................................
38
5.3.3 Estimated Cost..............................................................................................39
5.4
Terminal Storage Reservoir......................................................................................
40
5.4.1 Strategy Description......................................................................................
40
5.4.2 Project Assumptions and Costs....................................................................41
5.5
Aquifer Storage and Recovery..................................................................................44
5.5.1 Project Description and Analysis...................................................................44
5.5.2 Project Assumptions and Estimated Cost .....................................................
45
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5.6 Reuse of Treated Effluent.........................................................................................
46
5.6.1 Strategy Costs...............................................................................................49
5.6.2 Summary.......................................................................................................50
5.6.3 Permitting Issues...........................................................................................51
6 Long -Range Water Supply Plan.........................................................................................
51
6.1 Objectives and Issues...............................................................................................51
6.2 Solutions...................................................................................................................
52
6.3 Preferred Long -Range Water Supply Plan................................................................
55
6.4 Implementation of the Long -Range Water Supply Plan ............................................
57
6.4.1 Impacts of the Plan on Utility Finances.........................................................
57
6.4.2 Recommended Future Actions......................................................................58
Tables
Table 1. Growth factors used to determine future water demands.............................................10
Table 2. Historical, expected, high, and low annual and maximum -day demands.....................13
Table 3. Effects of demand reduction assumptions....................................................................16
Table 4. Population projections inferred from growth in residential connections ........................18
Table 5. Annual supplies currently available to the City of Plainview.........................................21
Table 6. Projected annual surpluses and needs for the City of Plainview, 2040 through
2070................................................................................................................................
23
Table 7. Expected maximum -day surpluses and needs for the City of Plainview, 2040
through2070...................................................................................................................25
Table 8. Parameters used for estimating project costs...............................................................
27
Table 9. Summary of supplies and costs of evaluated water supply strategies ..........................
28
Table 10. Water conservation baseline metrics and goals.........................................................
29
Table 11. Implementation schedule of Best Management Practices for the City of
Plainview.........................................................................................................................
29
Table 12. Costs and projected savings from BMPs based on Individual measures
implemented....................................................................................................................
30
Table 13. Summary of estimated cost for Dockum Aquifer wellfield...........................................
35
Table 14. Additional supplies potentially available from CRMWA member cities .......................
39
Table 15. Terminal storage reservoir options and costs.............................................................42
Table 16. Cost estimate summary for Option 3 of the Terminal Storage Reservoir with
storage for 14 days of maximum -day demands..............................................................43
Table 17. Summary of estimated cost for aquifer storage and recovery ....................................46
Table 18. TCEQ quality standards for reuse water.....................................................................49
Table 19. City of Plainview reuse costs (September 2018 dollars) .............................................
50
Table 20. Preferred Long -Range Water Supply Plan and triggers to implement specific
strategies.........................................................................................................................
56
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Figures
Figure 1. Monthly water production (January 2013 through December 2019)..............................
6
Figure 2. Maximum daily water production (Sept 2014 through December 2019)........................
7
Figure 3. Seasonal daily water demands......................................................................................
7
Figure 4. Monthly water billed by use type....................................................................................
8
Figure 5. Historical and projected annual water demands..........................................................12
Figure 6. Historical and projected maximum -day water demands..............................................13
Figure 7. Historical and projected population estimates inferred from growth in residential
connections.....................................................................................................................17
Figure 8. Changes in saturated thickness and well pumping rates from the City of
Plainview groundwater system........................................................................................
20
Figure 9. Projected annual supplies, demands, and needs for the City of Plainview ..................
23
Figure 10. Projected maximum -day supplies, demands, and needs for the City of
Plainview.........................................................................................................................
25
Figure 11. Existing wells in the Dockum aquifer identified with (a.) district numbers and
information on water quality (TDS, mg/L) and (b.) potential yield (gpm) near the
cityof Plainview...............................................................................................................
32
Figure 12. Total depth (feet) of existing wells in the Dockum aquifer .........................................
34
Figure 13. Simulated saturated thickness and production rates through time for the
Plainview wellfield when pumping is distributed uniformly across all currently
activewells......................................................................................................................
37
Figure 14. Simulated saturated thickness and production rates through time for the
Plainview wellfield when pumping rates are scaled based on initial saturated
thickness.........................................................................................................................
38
Figure 15. Site map of terminal storage reservoir.......................................................................41
Figure 16. Cost curve for terminal storage reservoir...................................................................
42
Figure 17. Simulated saturated thickness and production rates through time for the
Plainview wellfield when 1,000 acft/yr of recharge occurs ..............................................
45
Figure 18. City of Plainview Reuse Option, Phase 1..................................................................47
Figure 19. City of Plainview Reuse Option, Phase 2..................................................................48
Figure 20. Cost to implement the Long -Range Water Supply Plan per 1,000 gallons of
future demands (High Demands projection)...................................................................
57
Figure 21. Contribution of individual strategies to cost to implement the Long -Range
WaterSupply Plan..........................................................................................................
58
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Acronyms/Abbreviations
acft/yr
acre-feet per year
ASR
aquifer storage and recovery
BMP
best management practice
BOD5
biochemical oxygen demand, 5-day test
CBOD5
carbonaceous biochemical oxygen demand, 5-day test
CFU
colony -forming unit
City
City of Plainview
CRMWA
Canadian River Municipal Water Authority
gal
gallons
gpcd
gallons per capita per day
gpm
gallons per minute
HDR
HDR Engineering, Inc.
HPAS-GAM
High Plains Aquifer System Groundwater Availability Model
LRWSP
Long -Range Water Supply Plan
mg/L
milligrams per liter
mgd
million gallons per day
ml
milliliter
NTU
nephelometric turbidity units
TCEQ
Texas Commission on Environmental Quality
TDS
total dissolved solids
TWDB
Texas Water Development Board
UCM
Uniform Cost Model
WTP
water treatment plant
WWTP
wastewater treatment plant
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Long -Range Water Supply Plan ���
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Executive Summary I
In 2020, the City of Plainview (City) commissioned HDR Engineering, Inc. (HDR) to develop a
Long -Range Water Supply Plan (LRWSP) to guide the City in meeting future water supply
needs. This LRWSP was developed to meet the following objectives:
1. Provide sufficient annual supply volume,
2. Provide sufficient capacity to meet projected maximum day water demands, and
3. Promote conservation and education.
In coordination with City staff, HDR developed three alternative projections of future water
supply demands through 2070, for both annual supply volume and maximum -day demands,
evaluated the capability of the City's current water supply system to meet those projected
demands, and evaluated several water supply strategies to address projected future shortages.
Three alternative water demand projections were developed through consultation with City staff:
• Expected Demands
• High Demands
• Low Demands
These demand projections are based on projected growth rates of single- and multi -family
residential, commercial, and irrigation connections and projected rates of water use for each
connection type. Additional large single block increases in commercial/industrial demand were
also incorporated into the Expected Demands and High Demands scenarios to reflect the
possibility of one or more large commercial or industrial users locating in the City. Projections
were made for annual water demand in acre-feet per year (acft/yr) and maximum -day demand
in million gallons per day (mgd) through 2070.
The City uses two sources of supply — surface water (Lake Meredith) and groundwater provided
by the Canadian River Municipal Water Authority (CRMWA) and groundwater from a City -
owned wellfield with 15 active wells located throughout the City. Supplies from CRMWA can be
considered firm, with a total annual contractual volume of 3,799 acft/yr, although CRMWA
allocates water to its 11 member cities based on ongoing water demand projections and not
based on the maximum supply stipulated in contractual terms. The City's groundwater supply is
from the Ogallala Aquifer, which is projected to decline substantially over the next two decades
from regional agricultural pumping. This decline will negatively affect the City's wells and the
City's wellfield cannot be considered a long-term sustainable supply. If managed proactively, the
wellfield is expected to be able to support an annual supply of 1,200 acft/yr until the late 2030's
at which time supplies will begin to decline.
Figure ES 1 presents the annual and maximum -day demands, projected supplies available from
CRMWA and the City's wellfield, and projected needs (shortages) when the demands exceed
the annual supply or maximum production capacity. Based on this analysis, the City will
experience water supply shortages in the early 2040s as regional groundwater declines impact
the supply from the City's wellfield.
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During the development of this LRWSP, three primary issues were identified that should be
addressed:
• Diminishing local groundwater supplies
This will impact the capability of the City to supply maximum -day demands as well as
annual demands.
• Potential interruption of CRMWA supplies
The CRMWA transmission system is aging and has experienced pipeline failures in
recent years. Supplies from CRMWA could be interrupted from a number of events
including pipeline failures. A strategy to increase the reliability of the supply from
CRMWA should be initiated.
• Limited supply options
Located in the High Plains Region of Texas, limited options are available for new
supplies of water.
To address these issues, the following water supply strategies were evaluated and costs to
implement each strategy were estimated.
• Water conservation
• Obtain additional CRMWA supplies
• Develop additional City -owned groundwater
• Reuse water from the City's Water Reclamation Plant
• Aquifer storage and recovery (ASR)
• Terminal storage reservoir for CRMWA supplies
Based on the evaluations of these strategies, the LRWSP summarized in Table ES 1 is
recommended. The City has sufficient annual supplies and production capacity to meet
projected demands through at least 2040 if demands grow as projected and the City's
groundwater wellfield is able to sustain current well capacities. In lieu of establishing "need by"
dates, the plan identifies conditions that the City should monitor that should "trigger"
implementation of specific strategies. The expected year for the trigger to occur is shown, but
only to provide an estimated timeframe. Triggers are identified such that the City is expected to
have sufficient time to implement the strategy before needing the resource.
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6,000
e -
2020 2025 2030 2035 2040 2045 2050 2055 2060 2065 �7e
12
19
9 8
m
E
z
9
Y
Plainview GW Supply
0
4
s — 40 Demand Proiedion
Epeded Demand PtWdian91 CRAtIMA Supply
6 Low Demand PiopOon
2 — - Hgh Demand Needs
K 6q*ded Demand Needs
Low Demand Needs
2020 2025 2030 2036 204D 2045 2050 2055 me fMe s»
Year
Figure ES 1. Projected annual and maximum -day demands, supplies and needs.
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Table ES 1. Preferred Long -Range Water Supply Plan and triggers to implement specific strategies.
The City should adopt its updated water conservation plan
Water Conservation None
2021
and proactively begin implementing the BMPs identified in
the plan.
The City should continue to manage this resources and
Actively Manage Wellfield None
2021
attempt to limit annual pumping to 1,200 acft/yr, relying on
the groundwater supply to supplement CRMWA supplies
during high demand periods.
The reservoir will not increase annual supply from CRMWA,
Terminal Storage Reservoir None
2026
but will alleviate some dependence on groundwater and
immediately improve the reliability of the City's water supply.
Static water levels
This will occur in advance of substantial reductions in well
decline 10 feet
Aquifer Storage and Recovery
2027
capacities. The intent is to begin supplementing and
from current
maintaining well capacities prior to noticeable declines in
levels
production capacity.
Annual demands
A demand of 4,000 acft/yr is 80% of the combined CRMWA
Develop Phase I Non -Potable Reuse exceed 4,000
2031
and City annual supplies. Note that 4,000 acft/yr exceeds
acft/yr
the 2070 Expected Demands projection and this project
would only be needed under the High Demands projection.
Implement when demands exceed 80% of available annual
Annual demands supply. Could be implemented with discharge into the
Develop Phase II Potable Reuse exceed 4,400 2041 terminal storage reservoir. Note that 4,400 acft/yr exceeds
acft/yr the 2070 Expected Demands projection and this project
would only be needed under the High Demands projection.
BMP = best management practice, acft/yr = acre-feet per year, CRMWA = Canadian River Municipal Water Authority
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1 Introduction
The City of Plainview (City) is located in Hale County in the High Plains region of Texas. The
2020 U.S. Census reported a 2020 population of 20,187 persons'. Located roughly 47 miles
north of Lubbock and 76 miles south of Amarillo, Plainview
is the largest city in Hale County and serves as the seat of
"The future availability of potable
the county government. The City boasts a modern, 100-bed
water remains a common
hospital and hosts Wayland Baptist University and the
concem. There is interest in
South Plains College Plainview Center, which provides a
learning about and implementing
number of technical education programs and general
water conservation strategies."
education transfer courses, serving a 15-county area of the
— 2012 Comprehensive Plan
High Plains.
The City of Plainview continually strives to provide reliable and high -quality water to citizens to
foster growth and prosperity.
1.1 Purpose and Scope
In 2020, the Plainview City Council directed City staff to develop a plan to provide adequate
water supplies to meet the future water supply needs of retail and wholesale water customers to
ensure the long-term viability of the City.
This LRWSP provides a roadmap for the City to meet the future water supply needs of the City's
water customers, with the following objectives:
1. Provide sufficient annual supply volume,
2. Provide sufficient capacity to meet projected maximum -day water demands, and
3. Promote conservation and education.
This LRWSP presents the results of analyses and summarizes future water demands projected
through year 2070, estimates of current and future water supplies, needs (shortages) and
strategies to meet the needs. The strategies, if implemented, would help to meet the water
supply objectives of the City through year 2070.
2 Water Demand Projections
2.1 Current Water Use
The City obtains its primary water supply from the Canadian River Municipal Water Authority
(CRMWA) and supplements CRMWA supplies with local water supply wells owned by the City.
Based on billing data from January 2013 through December 2019, annual water usage has
ranged between 52 to 130 million gallons. Monthly water production from CRMWA and the
City's wells is shown in Figure 1. Maximum daily production from the combined sources is
shown in Figure 2. Annual and maximum daily production vary from year to year as climatic
' https://www.census.gov/quickfacts/plainviewcitvtexas
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conditions vary — more water is used during hot, dry years than in cooler, wetter years. As is
typical with most municipalities, the City's water customers use more water during the summer
months of May, June, July, and August, as shown in Figure 3, when significant quantities of
water are used to irrigate lawns and gardens.
The majority of the City's water demand is single-family residential use, followed closely by
commercial use. The amount billed in each water use category is shown in Figure 4.
This recent water use information was used as the basis for projecting future water demands.
140
120
0
0
M
rn
0 100
E
c
0
80
0
0
a
60
T
L
C
O
2 40
01
■City Groundwater
■ CRMWA
2013 2014 20^5 2016 2017 2018 2019
Figure 1. Monthly water production (January 2013 through December 2019).
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6
N
C
0 5
M
OI
C
O
C 4
O
U
7
O
a` 3
T
f0
0
E
7
E
X 2
l0
1
0
2014 2015 2016 2017 2018
Figure 2. Maximum daily water production (Sept 2014 through December 2019).
5
4
0
0
J F M A
Figure 3. Seasonal daily water demands.
2019
M J J A S O N D
Month
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140
120
100
40
20
0
2013 -
■ Irrigation
■ Multi -Family
■ Commercial
■ Residential
Figure 4. Monthly water billed by use type.
2.2 Future Water Demands
Water demand projections drive decisions concerning the City's future water supplies. Three
alternative water demand projections were developed for the LRWSP: Expected, Low, and
High. These projections are based on past water use patterns and three alternative projections
for future numbers of single-family and multi -family residential connections, commercial
connections, and irrigation connections through 2070. These projections were coupled with
assumptions regarding future water use by each type of connection to determine future water
demands by type of connection. The projections also reflect assumptions regarding the addition
of one or more single large commercial water users at certain future years. Potential new
municipal wholesale customers were not considered in the demand projections.
Annual water demands are the total volume of water needed by the City in a year, expressed in
units of acre-feet per year (acft/yr)2. Annual water demands are equivalent to average -day water
demands when expressed in units of million gallons per day (mgd).
2 An acre-foot is the volume of water that covers an area of one acre with one foot of depth. It is equal to
325,851 gallons.
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Maximum -day water demands represent the capacity of the water system needed to supply
water during the largest demand day of the year. Maximum -day demands are typically
expressed in units of mgd. Maximum -day demands for a municipality are usually about twice the
average day demands (expressed in mgd). For the City of Plainview, the maximum -day
demands from 2015 — 2019 have averaged 1.99 times the average -day demands. For purposes
of this LRWSP, annual demands are expressed in units of acft/yr and maximum -day demands
as mgd to differentiate between the two'.
2.2.1 Annual Water Demands
Future numbers of each type of connection were projected on an annual basis through 2070
using a series of annual growth rates, with faster growth rates occurring earlier in the planning
period and slower growth rates in later years.
Average daily use per connection type was determined from monthly billing data provided by the
City. Use per connection was assumed to decline annually for the Expected Demands and High
Demands projections due to increased awareness of the City's water conservation efforts and
general adoption of more water efficient plumbing fixtures. No reductions were assumed for the
Low Demands projection.
Future numbers of connections were multiplied by future water use per connection to estimate
future water demands for each type of connection. The individual projections for each of the four
connection types were added together to arrive at a total billed water demand. For the Expected
Demands and High Demands projections, additional commercial use was added to reflect the
addition of one or more large commercial users that would not be reflected by uniform annual
growth rates.
The water use per connection is based on monthly billing data which reflects only the water
measured through customer water meters. Total water produced is always greater than billed
because of unbilled water use such as firefighting and water main flushing and system leakage.
The projections were increased to account for an estimated 16 percent overall unbilled water
use.
Expected Demands — The Expected Demands projection assumes the following:
The number of residential, multi -family, commercial, and irrigation connections will
increase annually by 0.50, 0.25, 0.15, and 0.04 percent, respectively, through 2030, with
these rates slowing at different future dates.
• The water use per residential, multi -family, commercial, and irrigation connections will
decline annually by 0.25, 0.13, 0, and 0.25 percent, respectfully, through 2030, with
smaller rates of decline at different future dates.
• An additional 0.25 mgd of commercial demand starting in 2026.
3 Annual demands expressed in units of acft/yr can be converted to average -day units of mgd by dividing
by 1,120.
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Low Demands — The Low Demands projection assumes smaller rates of growth in residential
and multi -family connections and no change in the use per connection for any customer
classes. No additional commercial demand is contemplated in this scenario.
High Demands — The High Demands projection assumes greater annual increases in the
number of all connection types than the Expected Demands projection, with similar decreases in
use by each connection type through 2050, but no further decreases after 2050. This projection
includes additional commercial uses of 0.25 mgd in 2026, increasing to 0.50 mgd in 2031 and
0.70 mgd in 2051.
The starting (year 2020) number of connections and use per connection are shown in Table 1,
followed by a summary of the annual growth factors used to determine the future annual water
demands for each projection.
Table 1. Growth factors used to determine future water demands.
Number of connections in 20201 M Use per Connection in 2020 (gal/day)2 232.34 763.82 863.58 630.19
Expected Demands
nnual increase i e t'o '
° 0.25 0.15 0.04a
hrough 2030 (/°)
MI It
nnual increase in connections,
031 — 2050 (%) Mkx
20Vnnual increase in connections,
51 — 2070 (%) A
Annual decrease in use All _0.25mi -0.13
through 2030 (%) IMrW5
Annual decrease in use, 'O.M 1 -0. 1511 -0.08 IMI'-0.15
2031 through 2050 (%)
Annual decrease in use, 156 ft -0.05 IMIVI.
10
2051 through 2070 (%) MAW.
Additional commercial demand,
starting in 2026 (mgd) 0.25
Ir
Low Demands
Annual Increase in connections 0.10 0.05 0
through 2070 (%)
Annual decrease in use 0 0 0
through 2070 (%)
Additional commercial demand, 0
starting in 2026 (mgd)
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High Demands
Annual increase in connections
through 2035 (%)
�� 1.00�
MMM
Annual increase in connections,
MMM.O3
2036 — 2050 (%)
.50
Annual increase in connections,
2051 — 2070 (%)
0.01
Annual decrease in use,
through 2050 (%)
-0.251'
11=81
-0.13 160 � -0.25
Annual decrease in use,
2051 2070
0 0 0
V"L
through (%)
Additional commercial demand,
0.25
starting in 2026 (mgd)
Additional commercial demand, 0.50
2031 — 2040 (mgd)
Additional commercial demand, 0.70
2041 — 2070 (mgd)
1. The number of connections in 2020 is based on the number of connections in 2019 plus 0.15
percent (residential), 0.15 percent (multi -family), .08 percent (commercial), and .04 percent
(irrigation).
2. Water use per connection type is established as the average of years 2013 through 2019.
mgd = million gallons per day
Historical and projected annual water demands are shown in Figure 5 and Table 2. Each
demand projection is less than projected by the Texas Water Development Board (TWDB) for
the 2021 Llano Estacado (Region O) Regional Water Plan, except for the High Demands
projection which approaches the TWDB volumes starting in 2050.
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5,000
i
i
4,500
F
i
4,000 i
3,500
3,000
o }
a
c
m
c 2,500.
t
3
w 2,000
0
c
a �
1,500 1.
1,000
500 }
0
2010
2020 2030 2040 2050 2060 2070
Year
Figure 5. Historical and projected annual water demands.
2.2.2 Maximum -Day Water Demands
Maximum -day water demands were projected by multiplying the annual water demand
projections (expressed as average day demands in mgd) by projected maximum -day to
average -day demand ratios. The starting maximum -day ratio of 1.99 was established from the
average of the measured ratios from 2015 through 2019. This ratio was reduced by 0.1 percent
annually from 2026 through 2050 for the Expected Demands projection and by 0.1 percent
annually from 2026 through 2070 for the High Demands projection to estimate changes in
maximum -day water use due to different demand management strategies which may be
implemented by the City. The maximum -day ratio was not reduced for the Low Demands
projection.
Expected Growth — The maximum -day to average -day ratio is reduced by 0.1 percent annually
beginning in 2026 and continuing through 2050, with no reductions after 2050. This results in a
ratio of 1.94 in years 2051 through 2070.
Low Growth — This scenario assumes no change in the maximum -day to average -day ratio.
High Growth — The maximum -day to average -day ratio is reduced by 0.1 percent annually
beginning in 2026 and continuing through 2070. Using this assumption, the ratio is projected to
reduce to 1.94 by 2050 and to 1.90 by 2070.
Historical and projected maximum -day demands are shown in Figure 6 and Table 2.
12 1 December 1, 2021
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9
8
7
2
1
0
2010 2020 2030 2040 2050
Year
Figure 6. Historical and projected maximum -day water demands.
Table 2. Historical, expected, high, and low annual and maximum -day demands.
Expected Demands High Demands■
Annual D. D.
•• .-
2013 4,254
2014 3,481
2015 3,090 1' 4.40W
2016 3,366 9 6.04 'A Historical Der
2017
3,141 In
6.200
2018
3,323 10
5.72M
2019
3,196 1
5.69
2021
3,420
6.07 3,424 6.08
2022
3,431
6.09 3,440 6.10
2060 2070
3,413 6.06
3,417 6.06
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2023
3,443
6.11
3,456
6.13
3,422
6.07
2024
3,455
6.13
3,473
6.16
3,427
6.08
2025
3,461
6.14
3,489
6.19
3,432
6.09
2026
3,747
6.64
3,786
6.71
3,436
6.10
2027
3,753
6.65
3,802
6.73
3,441
6.11
2028
3,760
6.65
3,819
6.76
3,446
6.11
2029
3,766
6.66
3,836
6.78
3,450
6.12
2031
3,780
6.67
4,150
7.32
3,460
6.14
2032
3,788
6.67
4,167
7.34
3,465
6.15
2033
3,796
6.68
4,184
7.37
3,469
6.16
2034
3,804
6.69
4,202
7.39
3,474
6.16
2035
3,812
6.70
4,219
7.41
3,479
6.17
2036
3,820
6.70
4,226
7.42
3,484
6.18
2037
3,829 #
6.71
4,232
7.42
3,488
6.19
2038 3,83700 6.72 4,238 7.42 3,493 6.20
2039 3,845 6.73 4,244 7.43 3,498 6.21
2041
3,861
6.74
4,480
7.82
3,507
6.22
2042
3,870
6.75
4,487
7.83
3,512
6.23
2043
3,878
6.76
4,493
7.83
3,517
6.24
2044
3,886
6.77
4,499
7.83
3,522
6.25
2045
3,894
6.77
4,505
7.84
3,527
6.26
2046
3,903
6.78
4,512
7.84
3,532
6.27
2047
3,911
6.79
4,518
7.84
3,536
6.27
2048
3,920
6.80
4,524
7.84
3,541
6.28
14 1 December 1, 2021
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2049 3,928 6.80 4,530 7.85
2051
3,940 6.82 4,543
2052
3,943 6.82 4,549
2053
3,946 6.83 4,556
2054
3,949 6.83 4,562
2055
3,952 6.84 4,568
2056
3,955 6.84 4,575
2057
3,958 6.85 4,581
2058
3,961 6.85 4,588
2059
3,964 6.86 4,594
2061
3,971 6.87 4,606
2062
L 6,880 4,612
2063
3,9771 IL 6,.8Mt 4,618
2064
3,980 l_ft,4,624
2065
3,983 "M 4,631
2066
3,986 6.90W 4,637
2067
3,990 6.90 4,643
2068
3,993 6.9M 4,649
2069
3,996 6.91 4,655
M... • . �.
acft/yr =
acre-feet per year; mgd = million gallons per day
Long -Range Water Supply Plan ���
City of Plainview
3,546 6.29
7.85
3,556
6.31
7.86
3,561
6.32
7.86
3,566
6.33
7.86
3,570
6.33 4d
7.87
3,575
6.34
7.87
3,580
�i
6.35 .
7.87
3,585
6.36
7.88
3,590
6.3�A
7.88
3,595
6.38-M
7.88
3,605
6.40
7.89
3,610
6.40
7.89
3,615
6.41 ,
7.89
3,620
6.42
7.89
3,625
6.43
7.90
3,630
6.44
7.90
3,635
6.45
7.90
3,640
6.46
7.90
3,645
6.47
2.2.3 Effects of Demand Reduction Assumptions
The Expected Demands and High Demands projections reflect assumptions regarding
decreases in water use over time for each connection type, as shown in Table 1, and reductions
in the maximum -day ratio. These changes reduce annual water demands by 38 acft in 2031 and
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66 acft in 2070, and reduce maximum -day water demands by 0.47 mgd in 2031 and 0.72 mgd
in 2070, as shown in Table 3.
Table 3. Effects of demand reduction assumptions.
2031 Demands
No Use Reduction 3,818 4,216 3,460 6.78 7.48 6.14
w/Use Reduction 3,780 4,150 3,460 6.67 7.32 6.14
2031 Savings 38 66 0 0.11 0.16 0.006
2070 Demands
No Use Reduction 4,165 4,864 3,650 7.39 8.63 6.48
w/Use Reduction 3,999 4,661 3,650 6.92 7.91 6.48
2070 Savings 1 G4 0 0.47
acft/yr = acre-feet per year; mgd = million gallons per day
2.2.4 Population Projections Inferred from Growth in Residential Connections
The growth rates projected for each connection type were developed through consultation with
City staff. Future expected population for the City of Plainview can be inferred from those growth
rates by assigning an average number of persons to each single- and multi -family residential
connection. Based on past population estimates from the U.S. Census Bureau and connection
counts provided by the City, the average persons per residential connection (combined single -
and multi -family connections) from 2013 through 2019 was 3.24 persons per connection.
Historical population (2000 through 20204) and projected populations (2021 through 2070) are
compared in Figure 7 with projections provided by the TWDB for the 2021 Llano -Estacado
(Region O) Regional Water Plan.
The 2010 U.S. Census established the population of the City to be 22,194. In 2013, the Cargill
processing plant, the largest employer in the City at the time, closed due to a lack of incoming
cattle caused by the ongoing drought in the area.5 The closing of the Cargill plant resulted in the
relocation of an estimated 2,300 employees living in and around Plainview. This business was
also one of the largest customers serviced by the City's water system.
Populations for 2000, 2010, and 2020 are determined by the U.S. Census for those years. Populations
for 2013 through 2019 are mid -year estimates developed by the U.S. Census Bureau.
5 Manny Fernandez, "Drought Takes Its Toll on a Texas Business and a Town," The New York Times,
February 27, 2013.
16 1 December 1, 2021
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In 2020, the U.S. Census established the population of Plainview at 20,197, which is a 10
percent decline from the 2010 Census population caused primarily by the closing of the Cargill
facility. All three growth scenarios were developed considering that the population decline
caused by the Cargill closure will reverse and the City will again experience future periods of
population growth.
In 2013 the City adopted the Plainview Comprehensive Plan6, which forecast a population in
2040 of between 24,000 and 26,000 persons. This work was completed prior to the closing of
the Cargill facility and did not anticipate that event. Adjusted for the population lost from the
Cargill closing, the projections presented above are in agreement with City's 2012
Comprehensive Plan.
30,000
25,000
20,000
o
75 15,000 ----
0. —0— Historical
0
a +TWDB Prot(
—High Proted
10,000 Expected Pi
—Low Project
5,000
0 �.
2000 2010
2020 2030 2040 2050 2060 2070
Year
Figure 7. Historical and projected population estimates inferred from growth in residential connections.
6 https://www.i)lainviewtx.org/336/Comprehensive-Plan
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Table 4. Population projections inferred from growth in residential connections.
2025
21,265
20,905
21,788
2030
21,791
21,059
22,876
2040
22,881
21,370
24,613
2050
24,027
21,686
25,846
2060
24,662
22,007
26,487
2070
25,232
22,332
27,144
3 Current Water Supplies
3.1 CRMWA Supplies
CRMWA provides a combination of surface water from Lake Meredith and groundwater from the
Ogallala Aquifer in Roberts County. Groundwater from Roberts County is developed and
transmitted by the John C. Williams Aqueduct and Wellfield to a location south of Fritch, TX,
where it is blended with supplies from Lake Meredith. The blended supply is transmitted to
CRMWA's 11 member cities through a 322-mile aqueduct system that extends from Lake
Meredith through Amarillo and Lubbock to Lamesa. The aqueduct is roughly parallel to
Interstate 27, with a branch transporting water west to Levelland and Brownfield. CRMWA has
obtained additional groundwater rights in other areas of Roberts County and in Grey,
Hutchinson, and Wheeler counties intended to provide a long-term supply to CRMWA's member
cities.
Per contractual provisions between the City and CRMWA, the City has a right to 4.15 mgd of
the CRMWA Aqueduct capacity. The City's pro-rata share of the annual supply from CRMWA is
1,238 million gallons per year, or 3,799 acft/yr, a current allocation of 3.691 percent of
CRMWA's total supply. This equates to an average -day supply of 3.39 mgd, so the
authorization to take 4.15 mgd provides some capability to take greater than the average -day
supply for limited periods of time. Although production from the existing CRMWA wellfield will
likely decrease over time as aquifer levels decline, these supplies are considered firm under the
assumption that CRMWA will add additional wells, as necessary, to maintain existing production
capacity.
With the additional undeveloped supplies from Roberts, Grey, Hutchinson, and Wheeler
counties, supplies from CRMWA appear to be reliable and sustainable for many years, well
beyond the timeframe of the City's LRWSP. However, the CRMWA supplies can be considered
somewhat vulnerable because supply is dependent on the CRMWA Aqueduct, which was
constructed in the 1960s. The aqueduct system is aging, and failure along any part of its 322
miles could interrupt deliveries to Plainview until repairs are completed. In late 2015 and early
2016, the aqueduct experienced three failures that removed the aqueduct from service for at
least a week. CRMWA has performed a condition assessment and has installed emergency
bypasses around areas known to be vulnerable.
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Long -Range Water Supply Plan
City of Plainview
CRMWA has a long-term plan to construct an additional pipeline to deliver water from a
separate Roberts County wellfield to the CRMWA Aqueduct that would increase the total
groundwater supply from CRMWA by 58,240 acft/yr, of which Plainview's share (3.691 percent)
would be 2,150 acft/yr. CRMWA has not committed to a timeframe for construction of this
additional infrastructure. Based on its current capacity, the CRMWA Aqueduct would not be able
to transport the full volume of additional supply.
The maximum annual supply received by the City from CRMWA since 2013 was 2,595 acft in
2017. Because Lake Meredith water is often blended with groundwater from the Roberts County
wellfield, the City must treat the CRMWA supply as a surface water supply and operates a water
treatment plant that treats the CRMWA supplies to drinking water standards before introducing
the water into the City's water distribution system.
The City's water treatment plant has a rated capacity of 6.52 mgd, with the clarifiers currently
establishing the plant's production capacity. The water treatment plant provides greater
treatment capacity than can be supplied by CRMWA and treatment capacity does not limit the
City's water supplies.
3.2 City -Owned Groundwater Supplies
The City has 15 active wells, all located within the City and tied directly into the City's water
distribution system. Fourteen of the 15 wells have recorded production in the last 5 years. Texas
Commission on Environmental Quality (TCEQ) records' provide a "tested" yield for each of the
wells when it was drilled. The sum of these 15 tested yields is 12.2 mgd, although well yields in
an unconfined aquifer such as the Ogallala Aquifer will tend to decline with time as saturated
thicknesses decrease. The total capacity of the wells has not been fully used; the wells have
delivered as much as 5.98 mgd in recent years (July 13, 2016). This is equivalent to recent
maximum -day system demands of roughly 6 mgd.
Assuming a long-term supply from CRMWA of 2,600 acft/yr, based on recent annual deliveries
from CRMWA, the groundwater system might be required to provide an annual supply of as
much as 4,661 acft. In the Ogallala Aquifer, a minimum saturated thickness is required to
achieve the pumping rates desired in municipal wells. The assumption built into the planning
simulations performed with the High Plains Aquifer System Groundwater Availability Model
(HPAS-GAM) is that as saturated thickness approaches 30 feet, pumping rates will be reduced
and productivity will decrease. A simulation using the HPAS-GAM indicates that a pumping rate
of 4,661 acft/yr rate could be sustained for less than 10 years before significant declines in well
capacity occur.
A second simulation of the City's groundwater system indicated that 1,200 acft/yr could be
sustained for nearly two decades before some reduction in well capacities may occur. By 2070,
saturated thicknesses are projected to decline to the extent that the effective well capacities will
be zero. These simulations account for regional agricultural pumping pressures that cause
' TCEQ Drinking Water Watch, https:Hdww2.tceg.texas.gov/DWW/.
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water levels in the City to drop by one to two feet per year, regardless of whether the City uses
its wells. Results of the HPAS-GAM simulation are shown in Figure 8. Note that the simulation
reflected in Figure 8 assigned the 1,200 acft/yr pumping to the individual wells in proportion to
each well's use in the last five years, i.e., wells the City has used more in the last five years
were assigned proportionally greater pumping.
Based on the modeled simulations, the long-term supply of 1,200 acft/yr from the City's current
wells is not expected to be sustainable much past the 2050 decade due to regional declines in
saturated thickness resulting from continued agricultural pumping. For purposes of this plan,
City -owned groundwater supply was assumed to be unusable when the simulated annual
pumping declined below 300 acft/yr. This is projected to occur in 2055.
Change in Saturated Thickness at the Wells
—4
120 --- 7
- a
\. 11 \
100 12
--- 13
14
is
80
17
60
is
20
n \\\ -............_._.. _ _ _ _ 21
N 401 \' .Tn--------------------- ---------- 22
201 �.�.—
I
..... ...... ..................•-..a..u.0
. . .......:rr........=.'.«.��-nnnnn nnnn..n...... �
2020 2030 2040 2050 2060 2070
Change in Pump Rate at the Wells
— 4
12001------ ----------------------------------- --- 7
--s
11
1000� - 12
m --- 13
r - 14
c� w0i 15
A - — 16
- 17
a 6DOi - - is
20
221
-------------------------------- --- 22
-- --- TOWI
......................:::::::..........................
Figure 8. Changes in saturated thickness and well pumping rates from the City of Plainview groundwater
system.
3.3 Potential Reclaimed Water Supplies
The City operates the City -owned Water Reclamation Plant, which is authorized under Texas
Pollution Discharge Elimination Permit (TPDES) No. WQ0010537001 to discharge an annual
average of 3.3 mgd of effluent to Running Water Draw, a tributary of the White River. Production
20 1 December 1, 2021
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City of Plainview
reports from 2012 to 2019 indicate that the City has been discharging an average of 1.29 mgd,
with a minimum discharge of 1.18 mgd in 2018.
For purposes of establishing supply available for reuse, 1.18 mgd (1,322 acft/yr) of effluent is a
reasonably conservative estimate to use for planning purposes.
3.4 Overall Water Supply Reliability
3.4.1 Annual Supplies
The City of Plainview currently has 7,261 acft/yr of annual supply, comprised of 2,600 acft/yr
from CRMWA and 4,661 acft/yr of City -owned groundwater, based on recent usage of both
resources. As supply from the City's wellfield decreases, total available supply will decrease to
4,999 acft/yr in the mid-term (approximately 2040), consisting of the full 3,799 acft/yr contractual
supply from CRMWA and 1,200 acft/yr from the City's wells. This supply will further decrease as
the City's well capacities continue to decline and, ultimately, the City's supply will consist solely
of the 3,779 acft/yr supply from CRMWA.
The effluent from the City's Water Reclamation Plant could provide an additional 1,322 acft/yr
should the City decide to incorporate direct potable or non -potable reuse into the City's water
supply portfolio. This would increase available annual supplies to 6,321 acft/yr in 2040 and
5,121 acft/yr in 2070.
Overall, the City's current CRMWA and City -owned groundwater supplies are sufficient to meet
annual water demands projected under the High Demands projection through 2040 (4,250
acft/yr), and potentially through 2070 (4,661 acft/yr) if groundwater supplies decline less than
anticipated by the modeling or the City pursues direct potable or non -potable reuse to
supplement CRMWA supplies.
Table 5. Annual supplies currently available to the City of Plainview.
CRMWA 2,600 3,799 3,799
City -Owned Groundwater 4,661 1,200 0
Total Current Supply 7,261 4,999 3,799
Reuse 0 1,322 1,322
Total 7,261 6,321 5,121
1. Short-term supplies are based on current use of resources.
2. Mid-term supplies are based on full contractual quantity from CRMWA, reduced use of
City -owned groundwater to a sustainable annual quantity, and potential reuse supplies.
3. Long-term supplies are based on full contractual quantity from CRMWA and assumed
loss of current groundwater well capacity.
acft/yr = acre-feet per year
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Long -Range Water Supply Plan
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3.4.2 Maximum -Day Supplies
The City's water supply system must be capable of not only providing the required annual
volume to meet water demands but must also be able to provide those supplies at a rate to
meet the City's maximum -day demands. Maximum -day demands typically occur during the
summer months. During winter months, use is generally much less than average and during the
summer months maximum -day water use is roughly double the daily average.
Maximum -day supplies from CRMWA are limited to the 4.15 mgd contractual quantity.
Maximum -day supplies from the City's groundwater system are assumed to be 6 mgd through
2029, decrease to 4 mgd from 2030 through 2040, then decrease following a pattern similar to
the declines in annual pumping capacity.
Maximum -day demands are currently about 6 mgd and are expected to increase to 6.92 mgd
under the Expected Demands projection and to 7.91 mgd by 2070 under the High Demands
projection. Current City supplies can provide more than the projected maximum -day demands,
but this requires the City's groundwater sources be available because the CRMWA supply is
limited to the contractual capacity of 4.15 mgd. If the CRMWA contractual rate were increased
to facilitate maximum -day demands, the City's water treatment plant would also need to
increase capacity from its current 6.52 mgd. If groundwater levels decline as projected and
severely limit well capacities, the City will need to incorporate an alternative method of meeting
maximum -day demands.
4 Future Water Supply Needs
Future water supply need is the difference between future demand and existing supply,
accounting for the projected decline in groundwater availability. When future demand is greater
than the existing supply, the difference is referred to as a "need."
4.1 Annual Supply Needs
Annual supplies, projected demands, and resulting needs for the 2020-2070 period are shown
in Figure 9. Needs for additional annual supply are anticipated for the Expected Demands
projection starting in 2055. Under the High Demands projection, annual needs are projected
starting in 2045. Under the Low Demands projection, no needs are anticipated. Surpluses and
needs for the 2040 through 2070 period are shown in Table 6.
22 1 December 1, 2021
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City of Plainview r
6,000
5,000
Plainview GW Si
a 4,000
R
z
3,000
a
a
c
a
E
2.000
n
UDemandR�echon
d Demand Roiedion
1,000
a and Pr*dionmand Needsd Demand Needs
2020 2025 2030 2036 2040 2045 2050 2055 2060
Year
Figure 9. Projected annual supplies, demands, and needs for the City of Plainview.
Table 6. Projected annual surpluses and needs for the City of Plainview, 2040 through 2070.
2040
1,146
749
1,496
2041
944
325
1,298
2042
848
231
1,206
2043
761
146
1,122
2044
681
68
1,045
2045
607
(4)
974
2046
537
(72)
908
2047
474
(133)
849
2048
415
(189)
794
2049
361
(241)
743
2050
310
(290)
696
2051
268
(335)
652
2052
230
(376)
612
2053
195
(415)
575
2065 2070
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City of Plainview
ExpectedDemands High Demands Low Demane
Surplus/(Need) Surplus/(Need) Surplus/(Ne.
2054
162
(451)
541
2055(153)
_
al,
(769)
224
2056
2�! (156)
�*
(776)
219
2057
N (159)
(782)
214
F_ 2058
N& (162)
NJ
(789)
209
1 2059
Mir(165)
' W
(795)
204
ba 2060
NJ (169)
(801)
199
OF 2061
' (172)
(807)
194
p 2062
■ ' (175)
EL
(813)
189
1. 2063
on (178)
SM(819)
184
1 2064
we (181)
■IW
(825)
179
1 2065
(184)
NOW
(832)
174
2066
(187)
ML..
(838)
169
2067
(191)
on
(844)
164
2068
(194)
(850)
159
2069
(197)
(856)
154
2070
(200)
(862)
149
acft/yr = acre-feet per year
4.2 Maximum -Day Needs
Maximum -day supplies, demands, and needs are shown in Figure 10. Needs for additional
maximum -day supply capacity are anticipated under all three projections prior to 2048, with the
earliest (2042) and largest needs occurring under the High Demands projection. Surpluses and
needs for the 2040 through 2070 period are shown in Table 7. Even under the Low Demands
projection, for which annual supplies are sufficient through 2070, the City will require additional
supply capacity to meet maximum -day demand conditions, due to the expected reduction in the
well capacities of the City's groundwater supplies.
24 1 December 1, 2021
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Long -Range Water Supply Plan ���
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a.
c-No ernandProledm ---"----------------
y—Eqeded Deward Prgecilion CRMWA SuPPIY
a
c —taw Derrand Projecbon
E 2 ---EwDarrend
emand Needs
---ed Derrard Needs
— — Needs
0-
2020 2025 2030 2035 2040 2045 2050 2055 2060 2065 2070
Year
Figure 10. Projected maximum -day supplies, demands, and needs for the City of Plainview.
Table 7. Expected maximum -day surpluses and needs for the City of Plainview, 2040 through 2070.
2040
1.42
0.72
1.94
2041
1.26
0.18
1.78
2042
0.92
(0.15)
1.44
2043
0.61
(0.46)
1.13
2044
0.33
(0 74)
0.85
2045
0.07
(0.99)
0.58
2046
(0.17)
(1.23)
0.34
2047
(0.39)
(1.44)
0.12
2048
(0.59)
(1.64)
(0.08)
2049
(0.78)
(1.82)
(0.26)
2050
(0.95)
01 99)
(0.43)
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0
2051
2052
2053
2054
2055
f±
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
mgd = million gallons per day
(1.10)
(2.14)
(0.59)
(1.24)
(2.27)
(0.73)
(1.37)
(2.40)
(0.87)
(1.49)
(2.52)
(0.99)
(2.69)
(3.72)
(2.19)
(2.69)
(3.72)
(2.20)
(2.70)
(3.72)
(2.21)
(2.70)
(3.73)
(2.22)
(2.71)
(3.73)
(2.23)
(2.72)
(3.73)
(2.24)
(2.72)
(3.73)
(2.25)
(2.73)
(3.74)
(2.25)
(2.73)
(3.74)
(2.26)
(2.74)
(3.74)
(2.27)
(2.74)
(3.74)
(2.28)
(2.75)
(3.75)
(2.29)
(2.75)
(3.75)
(2.30)
(2.76)
(3.75)
(2.31)
(2.76)
(3.75)
(2.32)
(2.77)
(3.76)
(2.33)
5 Evaluations of Strategies to Meet Needs
Several water supply strategies were identified and evaluated that the City of Plainview should
consider pursuing to address the projected annual supply and maximum -day needs. Strategies
to increase annual supplies include a more aggressive water conservation program, developing
additional groundwater supplies from the Ogallala and Dockum aquifers, obtaining additional
supplies from CRMWA member cities that aren't using their full contracted amounts, aquifer
storage and recovery, and reuse of treated effluent. Each of those strategies also could
potentially address shortages in maximum -day supplies.
26 1 December 1, 2021
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In addition to the above strategies that would increase annual supplies and increase maximum -
day capacity, a terminal storage reservoir was evaluated that would temporarily store CRMWA
supplies to improve the reliability of the CRMWA supplies in the event of a pipeline failure and
provide the capability to increase maximum -day supplies.
The six water management strategies are evaluated on a consistent cost basis and subject to
similar technical assumptions. Unless otherwise noted, capital and annual operations and
maintenance cost estimates were prepared using the Uniform Cost Model (UCM) developed for
the TWDB to promote consistency in the 2021 regional water planning process. Current cost
estimates are based on September 2018 price indices so that the City's LRWSP is consistent
with the 2021 Regional and 2022 State Water Plans. Table 8 summarizes specific assumptions
adopted for parameters used in the UCM.
Table 8. Parameters used for estimating project costs.
Interest During Construction 3.00%
Rate of Return on Investments During 0.50%
Construction
Engineering, Legal, & Contingencies (Pipelines) 30% of Capital Costs
Engineering, Legal, & Contingencies (All Other 35% of Capital Costs
Facilities)
Debt Service Period 30 years
Annual Interest Rate 3.50%
Operations & Maintenance (Pipelines) 1.00% of Capital Costs
Operations & Maintenance (Pump Stations) 2.50% of Capital Costs
Power Costs $0.08/kilowatt-hour
Right of Way Land Acquisition Width 50 feet
Those potential strategies are listed in Table 9 along with their reliable supply, total project cost,
and annual unit cost in 2018 dollars.
• Total Project Cost — The costs for all project components including materials, labor,
equipment, engineering, legal, land acquisition and surveying, permitting, contingencies,
and interest during construction. In other words, the total cost to construct the project.
Annual Cost — The cost to deliver supplies on an annual basis including debt service
payments for construction costs, operation and maintenance, energy costs, and
payments for leases or water contracts.
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• Unit Cost — The annual cost per acre-foot to deliver supplies determined by dividing the
total annual cost during the debt service period by the annual reliable supply volume.
Detailed evaluations of each strategy are presented in the sections following Table 9.
Table 9. Summary of supplies and costs of evaluated water supply strategies.
Water Conservation
115
$34,265
$298
Additional Groundwater
2,000
$26,642,000
$1,834
Development
Additional CRMWA
862
N/A
$521
Supplies
Terminal Storage
N/A'
$10,815,000
N/A
Reservoir
Aquifer Storage and
1,000
$2,725,000
$212
Recovery
Reuse of Treated
1,120
$26,168,000
$1,207
Effluent
1. The terminal storage reservoir would not increase supplies from CRMWA, but would provide additional
flexibility in how supplies from CRMWA are used.
acft/yr = acre-feet per year; $/acft = dollars per acre-foot
5.1 Water Conservation
5.1.1 Strategy Description
Conserving existing water supplies through demand reduction is a cost-effective strategy
available to Plainview to extend available supplies and reduce maximum -day demands.
Water conservation is defined as "those practices, techniques, and technologies that will reduce
the consumption of water, reduce the loss or waste of water, improve the efficiency in the use of
water, or increase the recycling and reuse of water so that a water supply is made available for
future or alternative uses" (Texas Water Code §11.002 (a) (8) (B)). Because the City of
Plainview serves over 3,300 connections, the State of Texas requires the City to develop,
submit, and implement a water conservation plan and prepare updates to the plan every five
years (31 Texas Administrative Code, Chapter 363).
Pursuant to this study, the City has updated its water conservation plan to establish more
aggressive water conservation goals and to implement additional best management practices to
help achieve those goals. The Water Conservation Plan specifies a 5-year goal to reduce per
capita water use from the current 135 gallons per capita per day (gpcd) to 130 gpcd by 2026,
and a 10-year goal to further reduce water use to 127 gpcd by 2031. The plan identifies
additional gpcd reductions specifically for residential water use. The plan also established a goal
to reduce water loss to 14 percent by 2026 and to 13 percent by 2031.
28 1 December 1, 2021
00
Table 10. Water conservation baseline metrics and goals.
135
64
15%
gpcd = gallons per capita per day
131
59■_
14%
Long -Range Water Supply Plan L��
City of Plainview r
5.1.2 Adopted Best Management Practices
The following best management practices (BMPs) were included in the updated Water
Conservation Plan. Many of the BMPs outlined in the plan have already been implemented or
are ongoing. New BMPs are planned to be implemented as shown in Table 11.
Table 11. Implementation schedule of Best Management Practices for the City of Plainview.
Continuing Public
Education and
Information
Plumbing Codes
Water Conservation
Retrofit Program
Conservation -Oriented
Water Rate Structure
Production Meters
Universal Metering and
Meter Repair and
Replacement
Water Conserving
Landscaping
Water Loss Control
Measures
Already in place, however, the City
will expand public information
campaign in 2022. The City is
Yes current developing a one -page
handout to be made available to
the public and handed out at
conservation -oriented events.
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Leak Detection and Yes
Repair
Recycling and Reuse3':
Water rates will be monitored on
an annual basis and may be
adjusted depending on City goals.
The City is completing this Long -
Range Water Supply Plan to
explore opportunities.
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Water Conservation
No End of 2021 or
Coordinator
early 2022
Outdoor Water Use
No End of 2021 or
Restrictions
early 2022
Plumbing Fixture, Washer, and Landscape Rebate Program:
Toilet Rebates
No End of 2021 or
early 2022
Showerhead and Aerator No End of 2021 or
Kit Rebates early 2022
Clothes Washer Rebates No End of 2021 or early
2022
Urinal Rebates No End of 2021 or early
2022
The City Manager will appoint a
Water Conservation Coordinator.
Will be enacted upon adoption of
the Water Conservation Plan.
The City currently provides a
limited number of high efficiency
toilets to residents annually. The
City will discontinue this practice
and develop a system of rebates
for high -efficiency toilets,
showerhead and aerator kits, and
clothes washers for residences
and commercial establishments,
and urinals for commercial
establishments.
Waterwise Landscaping End of 2021 or early The City will explore options and
Rebates o No 2022 develop a program of rebates for
retrofit of existing landscaping.
5.1.3 Estimated Costs
The cost of implementing or expanding conservation programs can vary widely among the
individual programs depending on the level of effort and infrastructure required. Costs and
projected water savings were estimated using the Municipal Water Conservation Planning Tool
developed by the TWDBB and are presented in Table 12.
Table 12. Costs and projected savings from BMPs based on Individual measures implemented.
Individual Measures
High Efficiency
Toilet Rebate Single $113 26.3 44 $4,972 286.04 0.03
Family
High Efficiency
Toilet Rebate $113 34.7 33 $3,729 293.28 0.03
Multi Family
8 https://www.twdb.texas.gov/conservation/municipal/plans/doc/TWDB MWCPT vl.xlsm
30 1 December 1, 2021
376
High Efficiency
Toilet Rebate
Industrial,
$138
Commercial,
Institutional
Measures
Showerhead and
Aerator Kit
$10
Single Family
Showerhead and
Aerator Kit
$10
Multi Family
Clothes Washer
Rebate
$156
Single Family
Clothes Washer
Rebate
$156
Multi Family
Urinal Rebate
Industrial,
7
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14.2
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Long -Range Water Supply Plan
City of Plainview
L 92.27 � 1 L0.02
44 $440 40.49 0.004 1
33 $330 27.40 0.003
55 $8,580 171.55 0.02
33 $5,148 165.59 0.02
Commercial, $138 17 22 $3,036 102.21 0.01
Institutional
Measures
Clothes Washer
Rebate
Industrial, $ 33 _ .
Commercial, 0-4
InstitutionalR—
Measures
Total (Individual Measures) $34,265 1,610 0.17
System -Wide Measures
Water Loss
Reduction by 2% N/A N/A N/A N/A 2,356 0.25
over 10 years
Seasonal
Restrictions on N/A N/A N/A N/A 33,394 3.56
Outside Water Use
Total (System -Wide Measures) N/A 35,750 3.81
Total Annual Savings (1,000 gal) 37,360 3.98A
Total Annual Savings (acftlyr) 114.6
gpd = gallons per day; gpcd = gallons per capita per day; acft/yr = acre-feet per year
1
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The water demands for the Expected Demands and High Demands projections include specific
anticipated reductions in water use by connection type, as shown in Table 1. These reductions
in water use reduce projected annual demands and reflect increased awareness of the City's
water conservation efforts and general adoption of more water efficient plumbing fixtures. The
conservation savings shown above (114.6 acft/yr in 2031) reflect additional conservation
savings that are expected to be achieved through implementation of the BMPs described above.
5.2 Additional Groundwater Development
5.2.1 Additional City -Developed Groundwater from the Ogallala Aquifer
Due to the projected declines in groundwater levels shown in Figure 8, additional City -
developed groundwater from the Ogallala Aquifer would not be a viable long-term strategy.
While additional wells in the Ogallala Aquifer could increase supplies for the short term, it is not
a potential long-term supply strategy.
5.2.2 Additional City -Developed Groundwater from the Dockum Aquifer
This alternative envisions new wells drilled in the Dockum Aquifer near Plainview. The goal is to
produce about 2,000 acft/yr from a Dockum Aquifer wellfield.
5.2.2.1 WATER QUALITY, WELL YIELD, AND WELL DEPTH IN THE DOCKUM AQUIFER NEAR PLAINVIEW
The TWDB defines the official Dockum Aquifer as the portion of the aquifer where total
dissolved solids (TDS) is less than 5,000 milligrams per liter (mg/L). The TWDB estimate of
where this 5,000 mg/L transition zone occurs is on the southwest edge of the City as shown in
Figure 11.
ID-85.?2J�wisher Drill Yield-600
TDS_rJa \_—Flow�lieb=n/ Sher
1
r urnY ItID=85324 ID=85326 _ Drill Yleltl-760\III View-n/a
TDS-3590 TDS=n/a - Fbw Y.Cld-590 I Flow Meld=850 --
ID-90043 Drill Yield=n/a
TDS=2601 I0-85329 , Drill Vicki=n/a Flow Yield-n/a
TDS=2010 I Flow Y.6d=973y
I0=85288 ID=89003 Drill Yfeld=800 DrJI Yieltl=1000
TD5-2062 TDS=n/a Flow Yield=Na Fbw Yield=182
--WIINNE1lI-..
ID=30159 ID-29791 Drill Yield-500 Dr81 veld= 180
TDS=31700 Ii rDs=Nay Flow riela-Na�V Flow Yield=Nam
Y ID-26711 Dell Yield=6 -
TDS-771 Fbw Yield-n/a
my rrnty
legend Legend
Dohum Aaulfer Dockum AmNer
L.-
Well OOO m<ft TDs 0 2.5 5 7.5 10 ml Well �„�l TDS
0 2 5 5 7.5 L. -
-Mepr Roeds -..._ I —Mew RoeM !
Figure 11. Existing wells in the Dockum aquifer identified with (a.) district numbers and information on water
quality (TDS, mg/L) and (b.) potential yield (gpm) near the city of Plainview.
(Data collected from https://dockumstudy.hpwd.org/.)
In general, water quality in the Dockum Aquifer improves moving updip towards the outcrop, as
the age of the water decreases and less time has been available for dissolution of constituents
32 1 December 1, 2021
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Long -Range Water Supply Plan
City of Plainview
from the porous media. Updip in the Dockum Aquifer from Plainview is generally to the
northeast.
Two sources of information were used to inform the yield and water quality near the City: the
TWDB driller log database, and the HPWD Dockum Study database. The TWDB groundwater
database was not used because it contains no records of nearby Dockum wells. The TWDB
driller log database was used to look for records of both active and plugged Dockum wells. The
majority of records of Dockum wells being drilled in the area have plugging records, indicating a
dry hole or some other unfavorable condition.
Based on the HPWD Dockum study database, there are currently four existing wells within 20
miles northeast of the City with available data on either water quality (TDS, mg/L), potential yield
(gallons per minute [gpm]), or both (Figure 11). There are two additional wells approximately 20
miles to the east-southeast of the City with quality and/or yield information, and several wells
within 30 miles north-northwest. Lastly, Azteca Milling has one active Dockum well south of the
City within the >5,000 mg/L zone of the aquifer.
Water quality records are based on either grab sampling or a probe conductivity measurement.
The data on water quality in the area 20 miles northeast of the City is relatively consistent, on
the order of 2,000 mg/L TDS. The Azteca well to the south shows a TDS of 31,700 mg/L. The
water quality beneath Plainview is likely between those two values. However, where and how
fast the transition occurs is unknown, and would require a test -drilling program to determine.
Data on potential yield was estimated at the time of drilling or with HPWD-performed flow tests,
and with both methods in several cases (Figure 11 b). For potential yield data, most of the wells
show between 500 and 1,000 gpm, with the exception of well ID 85288 which shows a flow -test
yield of 182 gpm. The time -of -drilling yield of 1,000 gpm was either based on the permit (i.e.
what the permittee was hoping to achieve) or an overestimate by the driller, since the flow yield
provides the definitive estimate of productivity.
Information on the depth to the base of wells (feet) is available from driller's logs (Figure 12).
While not explicitly stated, it is assumed that most wells are drilled to the bottom of the Dockum
Aquifer. The Azteca Milling well to the south has a depth of 914 feet, while wells 20 miles to the
northeast have depths of approximately 800 feet. Wells drilled near the City are expected to be
approximately 900 feet deep.
5.2.2.2 PROJECT ASSUMPTIONS AND COSTS
When locating a Dockum Aquifer wellfield near the City, the strategy must balance the
improvement in water quality that could be achieved by locating the wellfield some distance to
the northeast, and the cost of constructing a pipeline to transport the raw water to a City
treatment plant. Typical brackish water treatment plants in Texas treat a raw water quality of
between 2,500 and 3,500 mg/L TDS9. Treating the seawater -like quality groundwater from the
Azteca Milling well would greatly increase the costs of the treatment plant.
9 hftps://www.twdb.texas.gov/innovativewater/desal/doc/Cost of Desalination in Texas rev.pdf
December 1, 2021 1 33
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Long -Range Water Supply Plan
City of Plainview
For the purposes of estimating cost, the wellfield was assumed to be located 5 miles northeast
of the City to achieve a raw water quality of 2,500 to 3,500 mg/L. If the City were to actively
pursue this strategy, a test -drilling program should explore the Dockum Aquifer water quality
near the northeast City limits, and then move further updip only as necessary to achieve the
target water quality.
N
Total -Depth =_860� is
t ',,�o un
Total Depth = 930 Total Depth = 830�
Total Depth = 760
Total Depth = 8100'Total Depth = 811
l ti
Total Depth = 760
f
�Td al Depth = 914 Total Depth = 618y
Total Depth = 673
my
Legend
Dockum Aquifer
• well 0 2.5 5 7.5 10 mi
> 5,000 mg/L TDS
— Major Roads
Figure 12. Total depth (feet) of existing wells in the Dockum aquifer.
(Data collected from hops://dockumstudy.hpwd.org/.)
The TWDB UCM was used to estimate the bulk of the project costs. The cost of the concentrate
disposal well (estimated at $3,000,000) was based on a personal communication from STRATA
Technologies, who specialize in Texas injection wells. Other key assumptions include:
1. Well capacities of about 500 gpm, with three wells required.
34 1 December 1, 2021
Long -Range Water Supply Plan ���
City of Plainview
2. Land acquisition of about 1,300 acres (basically two adjacent sections) to meet the 1.5
acre-foot per acre HPWD requirement.
3. Well depths of 900 feet.
4. Topography is basically flat between the City and land 5 miles to the northeast.
5. Two 5,280-foot, 8-inch pipelines to tie two of the wells to the third, near where the main
line begins. 5,280 feet is the minimum well spacing required by HPWD for >500 gpm
wells. While wells in the same wellfield may be allowed a variance from spacing rules,
the amount of interference that is likely to occur with high -capacity Dockum wells
warrants a wide spacing.
6. 5-mile, 12-inch main pipeline from wellfield to treatment plant.
7. 120 hp lift station to provide mainline pressure.
8. Brackish groundwater RO treatment plant.
9. A 4,800-foot injection well for disposing of brine concentrate. This depth is based on
existing saltwater disposal wells in Hale and Lubbock counties.
Table 13 shows the estimated cost of the Dockum Aquifer wellfield water supply strategy.
Overall project cost is estimated at $26,642,000.
Table 13. Summary of estimated cost for Dockum Aquifer wellfield.
Primary Pump Station (2 MGD)
Transmission Pipeline (12 in dia., 5 miles)
Wellfields (Production Wells, Disposal Well, Pumps, and Piping)
Water Treatment Plant (2 MGD)
TOTAL COST OF FACILITIES
Engineering and Feasibility Studies, Legal Assistance, Financing, Bond Counsel,
and Contingencies (30% for pipes & 35% for all other facilities)
Environmental & Archaeology Studies and Mitigation
Land Acquisition and Surveying (34 acres)
Interest During Construction (3% for 1 years with a 0.5% ROI)
TOTAL COST OF PROJECT
ANNUAL COST
Debt Service (3.5 percent, 20 years)
$1, 064, 000
$1,947,000
$5,758,000
$8,013,000
$16,782,000
$5,776,000
$1,686,000
$1,684,000
714 000
$26,642,000
$1,875,000
1
December 1, 2021 1 35
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Long -Range Water Supply Plan
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Operation and Maintenance
L
r
Pipeline, Wells, and Storage Tanks (1% of Cost of Facilities)
Intakes and Pump Stations (2.5% of Cost of Facilities)
Water Treatment Plant
Pumping Energy Costs (1793605 kW-hr @ 0.08 $/kW-hr)
TOTAL ANNUAL COST
Available Project Yield (acft/yr)
!F
Annual Cost of Water ($ per acft), based on PF=1
Annual Cost of Water after Debt Service ($ per acft), based on PF=1
Annual Cost of Water ($ per 1,000 gallons), based on PF=1
Annual Cost of Water after Debt Service ($ per 1,000 gallons), based on PF=1
5.2.3 Optimization of the City's Current Wellfield
$77,000
$27,000
$1,546,000
$143,000
$3,668,000
2,000
$1,834
$897
$5.63
$2.75
When simulating the yield through time to estimate future supplies available from the City's
existing wellfield, three simulations were performed to explore whether changing the average
production rates in the wellfield would increase overall longevity. The three simulations included:
Pumping wells at rates proportional to current pumping rates (the City currently uses
some wells, such as 13, 14, and 22 more than others). This simulation is reflected in the
current supply analysis shown in Figure 8.
2. Pumping distributed uniformly across all wells.
3. Setting well pumping rates based on initial saturated thickness.
The results of the three simulations are shown in Figure 8, Figure 13, and Figure 14. When
wells are pumped uniformly (Figure 13), rates begin to decline sooner than when wells are
pumped at rates proportional to current usage (Figure 8). Scaling the well rates by initial
saturated thickness (Figure 14) increases the longevity of the wellfield compared to uniform
pumping rates, but still does not perform as well as the existing City pumping strategy.
36 1 December 1, 2021
I •
120
100
e so \
V
F 60
40
20
2020
Long -Range Water Supply Plan ���
City of Plainview
—4
--- 7
-- 8
...... 11
' 12
�. --- 13
14
15
16
--- 17
18
20
21
_ _ --- 22
2030 2040 2050 2060 2070
1
— 4
1200
--------------- -,-
--- 7
- - 8
•••••• 11
1000
_ --
- 12
n
--- 13
````````•�-_-
- - 14
t� 800
- - ---
--- - - - - - _ _ . _ -- - --- - --- - -- - -- .. 15
16
--- 17
d 600
-- 18
20
E
__ — 21
400
--- 22
--- Total
200
--
--y---------
-
........ .......... ,,
0
2020 2030 2040 2050 2060 2070
Figure 13. Simulated saturated thickness and production rates through time for the Plainview wellfield when
pumping is distributed uniformly across all currently active wells.
1
December 1, 2021 1 37
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Long -Range Water Supply Plan
City of Plainview
— 4
120 --- 7
— - 8
�.` 11
100 �.� 12
--- 13
14
Y80 \ <� \\\ �'� \ 15
16
--- 17
$ 60 N. —.
c.. - 18
20
\\\\\� ` `21
_ — 22
-----------—
.. \` �� -----------------
20 '��� -.
:::::
..a•� ..........:::....................................
Change in Pump Rate at the Wells
-- — 4
1200-------------------------------- ---
11
7
1000
— 12
aoo About 17 years before _ 14
rates decline - 15
A _ -- 16
- --- 17
u
m 600 — - 18
oc ...... 20
a
E 21
400
-- 22
--- Total
200
uyyn vin n.nw—lTfl �.. �.. �.. �.. �...,. ss
0 2020 2030 2040 2050 2060 2070
Figure 14. Simulated saturated thickness and production rates through time for the Plainview wellfield when
pumping rates are scaled based on initial saturated thickness.
5.3 Additional CRMWA Supplies
5.3.1 Strategy Description
CRMWA provides surface water and groundwater to 11 member cities, including Amarillo,
Lubbock, Pampa, Borger, Plainview, Levelland, Brownfield, Lamesa, Slaton, Tahoka, and
O'Donnell. Some of the CRMWA member cities are not using their full contracted amounts.
These cities are potential partners to cooperatively develop a strategy to buy excess water in
their contract, which would provide additional CRMWA supply to Plainview and reduce some of
the costs for the cooperating members.
5.3.2 Water Availability
Member cities identified as potential candidates are limited to those that are "downstream" from
Plainview in the CRMWA Aqueduct. The proration of aqueduct capacities is contractually based
and member cities located "upstream" of Plainview would not have the contractual ability to
assign their supplies to Plainview because they do not have capacity in the aqueduct
38 1 December 1, 2021
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City of Plainview
downstream from their delivery locations. Note that City of Lubbock officials have indicated they
are not willing to participate.
Current contractual amounts, maximum usage from 2016-2020, and potential available supplies
are shown in Table 14 for CRMWA member cities potentially able to participate. Note that
CRMWA plans annual supplies based on member cities informing CRMWA of their planned
usage in the coming year. Therefore, CRMWA does not plan to supply the full contractual
amounts of its member cities annually, but appears to have the surface water, groundwater, and
transmission capacity to do so if needed.
Table 14. Additional supplies potentially available from CRMWA member cities.
Levelland
935,000
2,869
1,797
62.6%
1,072
Brownfield
736,000
2,259
1,472
65.2%
787
Lamesa
733,000
2,249
1,333
59.3%
916
Slaton
528,000
1,620
1,040
64.2%
580
Tahoka
154,000
473
323
68.2%
150
O'Donnell
94,000
288
126
43.8%
162
acft/yr = acre-feet per year; gal = gallons
Projected annual supply needs in 2070 are 200 acft under the Expected Demands projection
and 862 acft under the High Demands projection. Those needs could be met from one or more
of the potential member cities identified in Table 14. Under the High Demands projection need,
an additional 862 acf/yr of supply would increase the total CRMWA supply available to
Plainview to 4,563 acft/yr. This is equivalent to an average daily supply of 4.07 mgd, which is
less than the maximum contractual delivery rate from CRMWA of 4.15 mgd and within the
capabilities of the CRMWA system to deliver.
While obtaining additional CRMWA supplies from other CRMWA member cities would not by
itself provide sufficient maximum -day supply capacity to meet the projected maximum -day
needs, the additional supply could be received during lower -demand winter months, stored in
the terminal storage reservoir discussed in the next section, and then accessed as needed to
meet maximum -day demands.
5.3.3 Estimated Cost
Costs for obtaining additional CRMWA supplies would be the annual costs charged by CRMWA
to its member cities proportioned to the additional supply and aqueduct capacity used by
Plainview, plus some potential renumeration to the cooperating member cities for agreeing to
allow Plainview to use some of their contractual supplies from CRMWA.
1
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An additional supply of 862 acft/yr represents 0.837 percent of the total CRMWA contractual
obligations, so the City would be expected to increase its payments to CRMWA from its current
allocation basis of 3.691 percent to 4.528 percent.
Based on the CRMWA fiscal year 2019/20 report, the average cost applied to CRMWA member
cities was $1.27 per 1,000 gallons for the total volume supplied to member cities. This cost
varied from $0.88 to $1.60 based on how operating and capital costs are assigned to member
cities. Based on the maximum unit cost allocated to a member city ($1.60 per thousand gallons
for Levelland), the annual cost for an additional supply of 862 acft would be $449,414, or
$521 /acft.
5.4 Terminal Storage Reservoir
5.4.1 Strategy Description
Construction of a terminal storage reservoir will increase the reliability of water purchased from
CRMWA by providing storage should CRMWA experience a temporary disruption of service,
such as might occur from a pipeline failure. A reservoir could also be used to potentially
increase annual supply if used in conjunction with another source. The terminal storage
reservoir would be sited adjacent to the current location where CRMWA supplies are delivered
to the City. It was assumed that pressure from the CRMWA Aqueduct would be sufficient to fill
the reservoir. Water from the reservoir would be pumped to the City's water treatment plant
through a new pump station located adjacent to the reservoir through the existing raw water
transmission line. The pump station would be sized to deliver the High Demands projection
maximum -day demand of 7.91 mgd. A valve box would be installed on the current transmission
line from CRMWA to control flows into the reservoir and allow flows from CRMWA to bypass the
reservoir and flow directly to the water treatment plant. A potential configuration of the project is
shown in Figure 15.
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Figure 15. Site map of terminal storage reservoir.
5.4.2 Project Assumptions and Costs
Five alternative reservoir sizes were evaluated with storage volumes ranging from 73 to 752
acre-feet. Each alternative was assumed to be square and store water at a depth of 20 feet. The
cost for each alternative was computed using the TWDB Uniform Cost Model using the special
off -channel reservoir capability of the tool. Table 15 and Figure 16 show the estimated cost for
the 5 options, inclusive of appurtenant facilities. The preferred option is Option 3, which stores
340 acre-feet, equal to two weeks of maximum -day demands under the High Demands
projection. This is slightly greater than 31 days of CRMWA average -day supply. Additional
operational analyses that account for other financial and risk considerations beyond the scope
of this master plan can be completed to optimize the size of the project.
The terminal storage reservoir was assumed to be located near the CRMWA Aqueduct on land
currently zoned for agricultural use. For the purposes of estimating cost, we assume a small
pipeline to the reservoir and a valve box installed on the existing City of Plainview raw water
transmission line to control flows into the reservoir.
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The TWDB UCM was used to estimate the project costs. Key assumptions include:
1. Water depth of 20 feet
2. Normal freeboard of 6 feet
3. Slopes 3:1
4. Crest width of 8 feet
5. Surface area variable according to storage capacity
Table 15. Terminal storage reservoir options and costs.
Option 1: Store 3 days of
Maximum -Day Demands
Option 2: Store 7 days of
Maximum -Day Demands
Option 3: Store 14 days of
Maximum -Day Demands
Option 4: Store 21 days of
Maximum -Day Demands
Option 5: Store 31 days of
Maximum -Day Demands
acft = acre-feet
$10,000,000
$14,000,000
2 $12,000,000
a�
N
$10,000,000
O)
O
$8,000,000
E
H $6,000,000
O
Cj $4,000,000
$2,000,000
$0
$7,103,000.00
73
4
20
$8,325,000.00
170
8
20
$10,815,000.00
340
17
20
`
MM
$11,776,000.00
516
25
20
$13,655,000.00
752
38
20
I
I
i
I
I
i
I
i
i
0 100 200 300 400 500 600 700 800
Storage (acft)
Figure 16. Cost curve for terminal storage reservoir.
A summary of the estimated cost of the terminal storage reservoir and appurtenant facilities are
show in Table 16. Overall project cost is estimated at $10,815,000.
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Table 16. Cost estimate summary for Option 3 of the Terminal Storage Reservoir with storage for 14 days of
maximum -day demands.
Off -Channel Storage/Ring Dike (Conservation Pool 340 acft, 17 acres) $5,220,000
Primary Pump Station (7.91 MGD) $2,097,000
Pipeline $151,000
Integration, Relocations, & Other $50,000
TOTAL COST OF FACILITIES $7,518,000
Engineering and Feasibility Studies, Legal Assistance, Financing, Bond $2,946,000
Counsel, and Contingencies (30% for pipes & 35% for all other facilities)
Environmental & Archaeology Studies and Mitigation $30,000
Land Acquisition and Surveying (26 acres) $31,000
Interest During Construction (3% for 1 years with a 0.5% ROI) $290,000
TOTAL COST OF PROJECT $10,815,000
ANNUAL COST
Debt Service (3.5 percent, 20 years) $249,000
Reservoir Debt Service (3.5 percent, 30 years) $396,000
Operation and Maintenance
Intakes, Pipelines and Pump Stations (2.5% of Cost of Facilities) $54,000
Dam and Reservoir (1.5% of Cost of Facilities) $78,000
Pumping Energy Costs (27,720 kW-hr @ 0.08 $/kW-hr) $2,000
TOTAL ANNUAL COST $779,000
Available Project Yield (acft/yr) 340
Annual Cost of Water ($ per acft), based on PF=26.06 $2,291
Annual Cost of Water After Debt Service ($ per acft), based on PF=26.06 $394
Annual Cost of Water ($ per 1,000 gallons), based on PF=26.06 $7.03
Annual Cost of Water After Debt Service ($ per 1,000 gallons), based on $1.21
PF=26.06
Note: One or more cost element has been calculated externally.
Available yield of the project assumes one cycle of reservoir storage annually.
December 1, 2021 1 43
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5.5 Aquifer Storage and Recovery
5.5.1 Project Description and Analysis
An ASR strategy was considered that would include drilling ASR wells inside the footprint of the
City's wellfield, and recharging water to the Ogallala Aquifer during winter months when
demands are low. The ASR wells would be dual-purpose wells, i.e. they would provide both
recharge and recovery, when needed. Single -purpose wells were considered that would provide
recharge only (near existing production wells) but given the need to periodically backflush the
wells by setting temporary pumps, the labor resources required make setting permanent pumps
the recommended option.
Operation of four ASR wells were simulated at locations near existing wells 13, 14, 15, and 22.
The wells were assumed to be able to store 1,000-acre feet total during the low -demand months
starting in 2030. This would equate to each well recharging at about 300 gpm for 6 months out
of the year. The simulations were carried out using an annual stress period, so the actual
months and recharge rates were not specified.
Figure 17 shows the results of the simulation. The change in saturated thickness for wells 13,
14, 15, and 22 shows a slight increase in 2030 as a result of the recharge. The wellfield can
sustain pumping of 1,200 acft/yr until about 2040, which decreases to about 1,000 acft/yr by
2070. A comparison between Figure 17 and Figure 8, indicates that the ASR strategy increases
the wellfield's ability to sustain 1,200 acft/yr by about 4 years, but more importantly increases
the 2070 productivity by more than 400 acft/yr, providing a long-term sustainable supply of
1,000 acft/yr from the City's wellfield. This would also maintain the wellfield's capability to supply
maximum -day demands of at least 3 mgd.
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Change in Saturated Thickness at the Wells
— 4
120 ___ 7
— - 8
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100 �.\ 12
--- 13
14
Y 80 \' 15
16
9 17
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20
21
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=— — — — — — — — — — — — — — — — —
— — — — — — — — — — — — — — — — — — —
— — — — — — — —
------------------ ..
::::::t:::::i:i:ii::::ii:::i:::i:i::i::ii::: i:::l:::i:i iiiiiieii:::::::T
.....................................................................
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0
2020 2030 2040
2050 2060
2070
Figure 17. Simulated saturated thickness and production rates through time for the Plainview wellfield when
1,000 acft/yr of recharge occurs.
5.5.2 Project Assumptions and Estimated Cost
The TWDB UCM was used to estimate the cost of the project. Key assumptions:
1. Well capacities of 300 gpm
2. Well depths of 330 feet, based on the range in depths of nearby existing wells
3. Wells located on existing City -owned land
4. System pressures sufficient to force recharge (no lift stations)
5. 500 feet of 8-inch line per well for connecting to the existing distribution system
Table 17 shows the estimated cost of the project, which comes to $2,725,000. This cost does
not include costs to treat the additional water used for recharge.
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Table 17. Summary of estimated cost for aquifer storage and recovery.
L Wellfields (Wells, Pumps, and Piping)
06. TOTAL COST OF FACILITIES
r
Engineering and Feasibility Studies, Legal Assistance, Financing, Bond
ounsel, and Contingencies (30% for pipes & 35% for all other facilities)
Environmental & Archaeology Studies and Mitigation
Interest During Construction (3% for 1 years with a 0.5% ROI)
TOTAL COST OF PROJECT
ANNUAL COST
Debt Service (3.5 percent, 20 years)
h Operation and Maintenance
bPipeline, Wells, and Storage Tanks (1% of Cost of Facilities)
TOTAL ANNUAL COST
5.6 Reuse of Treated Effluent
$1,958,000
$1,958,000
$685,000
$9,000
73 000
$2,725,000
$192,000
$20,000
$212,000
Wastewater reuse uses treated wastewater effluent as a replacement for potable water supply,
reducing the overall potable water demand. Wastewater reuse typically involves a capital project
connecting the treatment plant discharge facilities to an individual area that has a relatively high,
localized use that can be met with non -potable water. Examples most frequently include the
irrigation of golf courses and other public lands and specific industries or industrial use areas.
Wastewater reuse can be classified into two forms, defined by how the reuse water is handled.
• Direct Reuse —Treated wastewater is delivered directly from the wastewater plant to the
place of use (also called "flange -to -flange").
• Indirect Reuse —Treated wastewater is discharged to a river, stream, or lake for
subsequent diversion downstream (also called "bed and banks").
The City of Plainview currently does not use any wastewater effluent as a reuse water supply;
however, the City is evaluating a project to provide a portion of their effluent discharge as a
reuse supply to local golf courses and other open areas with a possible second phase to deliver
highly -treated effluent back to the water treatment plant. Phase 1 of the project would use up to
50 percent of the average effluent discharged from the wastewater treatment plant (WWTP), or
about 0.5 MGD (Figure 18). This reuse would be treated to Type II reuse standards with tertiary
treatment and disinfection being added at the WWTP. This treated effluent would then be
delivered to a local golf course through a 12-inch diameter pipeline. The pipeline would be sized
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to deliver 2 mgd as a peak use irrigation supply. Other potential areas that could utilize the
reuse supply are shown in Figure 18. These would require additional transmission lines to
deliver the treated effluent to those locations.
Figure 18. City of Plainview Reuse Option, Phase 1.
Phase 2 of the project would use up to 100 percent of the average effluent from the WWTP, or
about 1.0 mgd (Figure 19). With this phase, the original pipeline would be extended to allow the
effluent to be delivered to the City's water treatment plant. In addition, a 1-mgd advanced
treatment facility would be added to the existing WWTP. This would provide operational
flexibility to take all the reuse water for direct potable use or meet non -potable reuse demand
along the pipeline route (golf course, airport, recreation fields, or cemeteries).
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Figure 19. City of Plainview Reuse Option, Phase 2.
All direct reuse water supply options assume that treated wastewater remains under the control
(in pipelines or storage tanks) from the wastewater treatment plant to the point of use.
Wastewater reuse quality and system design requirements are regulated by the TCEQ through
30 Texas Administrative Code §210. TCEQ allows two types of reuse as defined by the use of
the water and the required water quality:
• Type 1 — Public or food crops generally can come in contact with reuse water; and
• Type 2 — Public or food crops cannot come in contact with reuse water.
Current TCEQ criteria for reuse water are shown in Table 18. Trends across the country
indicate that criteria for unrestricted reuse water will likely become more stringent over time. The
water quality required for Type 1 reuse water is more stringent with stricter requirements for
oxygen demand (BOD5 or CBOD5), turbidity, and fecal coliform levels.
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5 mg/L
3 NTU
20 CFU / 100 ml'
75 CFU / 100 m12
20 mg/L
15 mg/L
200 CFU / 100 ml;MM
Table 18. TCEQ quality standards for reuse water.
BOD5 or CBOD5
Turbidity
Fecal Coliform
Fecal Coliform (not to exceed)
BOD5
or CBOD5
Fecal Coliform
Fecal Coliform (not to exceed)
BOD5 30 mg/L
Fecal Coliform 200 CFU / 100 ml'
Fecal Coliform (not to exceed) 800 CFU / 100 m12
geometric mean
2 single grab sample
mg/L = milligrams per liter; ml = milliliter
BOD5 = biochemical oxygen demand, 5-day test
CBOD5 = carbonaceous biochemical oxygen demand, 5-day test
NTU = nephelometric turbidity units
CFU = colony -forming unit
5.6.1 Strategy Costs
Costs associate with this strategy are presented in Table 19. Assumptions associated with
these costs include the following.
• The advanced water treatment plant would be constructed on City -owned land adjacent
to the WWTP,
• The capacity of the pump station, advanced water treatment plant and transmission
pipeline include an estimated 5 percent downtime; and
• The project is assumed to have a 2-year construction period.
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Table 19. City of Plainview reuse costs (September 2018 dollars).
Primary Pump Station (2 MGD)
Transmission Pipeline (12 in dia., 19897 feet)
Transmission Pump Station(s) & Storage Tank(s)
Two Water Treatment Plants (2 MGD and 2 MGD)
Advanced Water Treatment Facility (1 MGD)
TOTAL COST OF FACILITIES
Engineering and Feasibility Studies, Legal Assistance, Financing,
Bond Counsel, and Contingencies (30% for pipes & 35% for all other
facilities)
$1,006,000
$1,072,000
$3,328,000
$5,148,000
$1,297,000
$1,297,000
$1,707,000
$1,707,000�
--
$9,445,000
$7,338,000
$18,669,004
$2,402000 $6,277,000
Environmental & Archaeology Studies and Mitigation $108,000 $160,000
Land Acquisition and Surveying (30 acres) $224,000 $361,000
Interest During Construction (3% for 1 years with a 0.5% ROI) $277,000 $701,000
TOTAL COST OF PROJECT $10,349,000 $26,168,000
ANNUAL COST
Debt Service (3.5 percent, 20 years)
Operation and Maintenance
Pipeline, Wells, and Storage Tanks (1% of Cost of Facilities)
Intakes and Pump Stations (2.5% of Cost of Facilities)
Water Treatment Plant
Advanced Water Treatment Facility
Pumping Energy Costs (57226 kW-hr @ 0.08 $/kW-hr)
TOTAL ANNUAL COST
Available Project Yield (acft/yr)
Annual Cost of Water ($ per acft)
Annual Cost of Water After Debt Service ($ per acft)
Annual Cost of Water ($ per 1,000 gallons)
Annual Cost of Water After Debt Service ($ per 1,000 gallons)
$728,000 $1,841,000
$46,000
$64,000
$25,000
$27,000
$602,000 $602,000
$0
$642,000
$5,000
$17,000
$1,406,000
$3,193,000A
560
1,120 11114
$2,511
$2,851
$1,211
$1,207-1
$7.70
0§ $8.7a
$3.71
111
$3.70 4
5.6.2 Summary
The advanced treatment facilities would be constructed on City -owned property, which is
currently being used for similar purposes and environmental issues should be minimal. The
transmission line corridor that would convey the reclaimed should be selected to avoid
potentially sensitive areas.
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Due to the nature of the project, it is assumed that a public outreach plan is needed for the
proposed reuse project. Advanced treatment design considerations should include real-time
monitoring and regular sampling to ensure process performance and avoid any acute episode of
pathogens in the reclaimed water.
5.6.3 Permitting Issues
The drinking water produced for the potable reuse project would meet or exceed all state and
federal drinking water standards. TCEQ is currently developing potable reuse guidance
requirements to be applied to proposed projects and to be used as the basis for reviewing
permit applications. TCEQ will require a pilot study prior to regulatory approval and for
determining design values for the treatment technologies. Treatment requirements for any
reclaimed water as a drinking water source may consider the pretreatment program, influent
wastewater quality, vulnerability assessment of the collection system, results of effluent quality
sampling/monitoring data, and wastewater treatment process.
Stream crossings would be subject to Section 404 of the Clean Water Act. Due to the minimal
and temporary impacts associated with the pipeline installation, it is likely that most of the
proposed project would be authorized by Nationwide Permit 12.
6 Long -Range Water Supply Plan
6.1 Objectives and Issues
This LRWSP is developed to meet three primary objectives:
• Provide sufficient annual supply volume to meet the projected future annual demands.
• Provide sufficient supply capacity to deliver maximum -day demands.
• Promote efficient use of water through conservation and education.
Through this planning process, the following tasks were completed:
• Annual water demands were projected for three alternative future projections.
• Maximum -day water demands were projected for the three same scenarios.
• The current and future annual and maximum -day supply capacities of the City's two
current water supplies were established.
• The reliability of the City's existing supplies was evaluated.
• The City's Water Conservation Plan was updated to include new, more aggressive Best
Management Practices.
• Strategies were identified and evaluated to meet the three objectives — annual supply,
maximum -day supply, and efficient use of water.
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Three primary issues were identified that the LRWSP needs to address.
Diminishing Local Groundwater Supplies — The City's low-cost, seemingly reliable
groundwater supply is declining due to regional groundwater pumping for irrigation. In
the future, declining regional groundwater levels will reduce the capacities of the City's
wells and the ability of the wells to provide a reliable annual supply. More importantly,
however, the City will not be able to rely on the wells to meet maximum -day demands as
regional groundwater levels continue to decline and well capacities diminish.
Potential Interruption of CRMA Supplies — CRMWA has developed a long-term (greater
than 100-years) supply of water from wellfields in Roberts County and the surrounding
area, which is supplemented with surface water from Lake Meredith when supplies are
available from the reservoir. Unfortunately, the supply from CRMWA is transmitted to the
CRMWA member cities through an aging aqueduct and supplies can be interrupted with
a pipeline failure or other disruption of the CRMWA facilities. The City has relied on its
own wellfield to supplement CRMWA supplies but diminishing regional groundwater will
eventually eliminate or limit the viability of this resource. The City will no longer be able
to provide short-term replacement of CRMWA supplies or supplement CRMWA supplies
to meet maximum -day demands at the required pumping rates.
Limited Supply Options — Located in the High Plains Region of Texas, limited options are
available for new supplies of water.
Combined, the contracted supply from CRMWA and the supply from the City -owned wellfield
appear sufficient to meet the City's annual water supply requirements through 2044 under the
High Demands projection and through 2054 under the Expected Demands projection. The
CRMWA supply is insufficient by itself to meet current maximum -day demands and is
supplemented during high demand conditions by the City's wellfield. As the capacity of the
City's wells decreases, the City will lose the capability to supplement CRMWA supplies. The
combined CRMWA and City -owned wellfield are projected to not meet maximum -day demands
by 2042 under the High Demands projection and 2046 under the Expected Demands projection.
Under the Low Demands projection, the CRMWA supplies are sufficient to meet annual water
demands through 2070, but by 2046 declining regional groundwater levels will cause the City's
wellfield capacity to be insufficient to supplement CRMWA supplies to meet maximum -day
demands.
6.2 Solutions
Multiple solutions were identified and evaluated to mitigate the issues identified above. A brief
discussion of each is provided below, followed by a preferred Long -Range Water Supply Plan.
Note that no single strategy that has been evaluated in this study will be sufficient to meet both
the annual and maximum -day demands projected under the three alternative scenarios.
Increase water use efficiency and reduce maximum -day demands. — The City's updated Water
Conservation Plan is more proactive than previous plans and is intended to facilitate more
efficient water use by its citizens and customers. However, as shown in Table 3, the demand
projections already incorporate a level of savings in per -connection use and the City's
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maximum -day to average -day demand factor. Those reductions are consistent with the
expected results of the City's recently adopted Water Conservation Plan. Solutions provided in
this plan are necessary over and above the City's planned water conservation efforts. Water
savings due to proactive conservation measures are important but are insufficient by
themselves to meet the City's water supply needs.
Provide an alternative supply to replace the City's diminishing groundwater. — This plan
identifies and evaluates three alternatives to replace the groundwater supply that is gradually
being lost due to regional declines in groundwater levels.
• Obtain additional CRMWA supply
Additional CRMWA supply could be obtained from other CRMWA member cities. A
relatively modest annual amount of 788 acft would provide sufficient annual supply.
However, the CRMWA system appears configured to provide primarily average -day
demands and the additional CRMWA supplies would be insufficient to help the City meet
future maximum -day demands.
• Develop additional City -owned groundwater
Additional wells developed in the Ogallala Aquifer could be added to supplement the
City's existing wellfield, but they would be subject to the same regional groundwater
declines and would provide only a temporary solution.
The City could develop a supply from the deeper, brackish/saline Dockum Aquifer.
Information regarding the Dockum is limited, and an extensive groundwater investigation
would be needed to identify feasible locations for wells. This solution would also require
an expensive desalination system to treat the water to potable quality.
Reuse water from the City's Water Reclamation Plant
This strategy is recommended for the City in the 2021 Llano -Estacado Regional Water
Plan. This would provide a reliable, sustainable supply of water entirely owned and
controlled by the City that would not be subject to climatic conditions. Implementation of
a reuse water supply could be phased, such that non -potable water is used initially (for
irrigation) followed by additional water treated to potable water quality as demands
increase. Supplies from a reuse system would provide limited maximum -day supply
capacity, essentially equivalent to the average -day supply provided by the reuse system.
Supplement the City's groundwater to extend the supply. — Groundwater model simulations
indicate the City's wellfield capacity will decrease rapidly under current production volumes.
Groundwater supplies can be extended past 2040 if annual pumping from the City's wellfield is
limited to 1,200 acre-feet. Two alternatives were identified and evaluated to supplement the
City's groundwater and extend its supply.
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• Actively manage the current wellfield
Groundwater production data provided by the City indicate that the City relies on some
wells more heavily than others, recognizing that some wells are more reliable and
provide greater capacity. It appears that the manner in which the City currently divides
production between its wells optimizes the long-term supply. HDR recommends that the
City continue to obtain supplies from its wellfield similar to its recent distribution but
reduce the annual amount pumped to about 1,200 acft. This supply volume should be
pumped primarily during summer months to supplement CRMWA supplies to meet
higher summer demands.
• Aquifer Storage and Recovery (ASR)
CRMWA Supply. The City currently has an excess of annual supply available from
CRMWA per its total contracted quantity. The City could request CRMWA to increase its
annual allocation to Plainview and use the extra supply to provide water to an ASR
system using potable water provided by the City's water distribution system.
Reuse Supply. As the City water demands begin to more fully use the supply from
CRMWA, the City could transition over time to use reuse supply as the source of water
for the ASR system. This might come from the Direct Potable Reuse identified as Phase
II in the evaluation presented previously or the City could construct a dedicated
transmission system to deliver water to the ASR wells.
Reuse Supply through the Terminal Storage Reservoir. If the City elects to construct the
terminal storage reservoir to improve the reliability of the CRMWA supplies and provide
a source to meet maximum -day demands, reclaimed water could also be stored in the
reservoir before being treated by the City's water treatment plant and used to provide
water for ASR through the City's water distribution system. This would likely require a
level of treatment similar to Phase 11 of the reuse strategy.
Improve the reliability and maximum-dav capacity of the CRMWA suDDly. — The
CRMWA supply is subject to being interrupted by pipeline failures and does not provide
sufficient capacity to meet maximum -day demands. This will become particularly
important as the City's groundwater supply capacity diminishes over time and its ability
to provide peaking supply decreases.
Terminal Storage Reservoir
Construction of a terminal storage reservoir would provide two distinct benefits to
Plainview:
1. Improve the reliability of the CRMWA supplies. Following a series of recent pipeline
failures, CRMWA completed a condition assessment that identified locations
specifically vulnerable to failure and CRMWA has constructed bypasses around
those pipeline sections. However, the entire CRMWA system is aging and long
pipelines like the CRMWA Aqueduct are vulnerable lifelines. Providing a multi -day
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volume of storage local to Plainview would greatly improve the reliability of the City's
supply, particularly as groundwater capacity declines in the future.
2. Provide a source to meet maximum -day demands. The City's water treatment plant
has the capacity to meet current maximum -day demands but the maximum delivery
rate from CRMWA will not allow the plant to fully use this capacity when needed. As
the City's groundwater capacity continues to decline it will become increasingly
important to maximize the ability to provide water from CRMWA.
• Option: Increase capacity of the City's water treatment plant.
If groundwater levels decline and the wellfield capacity is not maintained as envisioned,
it may be necessary to increase the capacity of the water treatment plant to 8 mgd to
provide the capacity to supply maximum -day demands in the absence of supplemental
groundwater supplies.
Based upon the forgoing discussion, the following outlines a preferred plan for the City to
implement to provide sufficient annual supply and the capacity to meet projected maximum -day
demands. The focus of the plan is meeting the more aggressive High Demands projection.
Should future demands follow the Expected Demands projection the plan would be similar, but
the reuse supply projects would be unnecessary. A plan for meeting the Low Demands
projection would focus primarily on providing sufficient capacity to meet maximum -day demands
if the City's wellfield capacity decreases as expected.
6.3 Preferred Long -Range Water Supply Plan
An overall plan is presented in Table 20 with the recommended strategies in the order
recommended for implementation. The City has sufficient annual supplies and production
capacity to meet projected demands through at least 2040 if demands grow as projected and
the City's groundwater wellfield is able to sustain current well capacities. In lieu of establishing
"need by" dates, the plan identifies conditions that the City should monitor that should "trigger"
implementation of specific strategies. The expected year for the trigger to occur is shown, but
only to provide an estimated timeframe. Triggers are identified such that the City is expected to
have sufficient time to implement the strategy before needing the resource.
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Table 20. Preferred Long -Range Water Supply Plan and triggers to implement specific strategies.
Water Conservation
None 2021
44M
Actively Manage Wellfield
The City should adopt its updated water conservation plan
and proactively begin implementing the BMPs identified in
the plan.
The City should continue to manage this resources and
attempt to limit annual pumping to 1,200 acft/yr, relying on
the groundwater supply to supplement CRMWA supplies
during high demand periods.
The reservoir will not increase annual supply from CRMWA
Terminal Storage Reservoir None 2026 but will alleviate some dependence on groundwater and
immediately improve the reliability of the City's water supply.
Static water levels This will occur in advance of substantial reductions in well
decline 10 feet capacities. The intent is to begin supplementing and
Aquifer Storage and Recovery from current 2027 maintaining well capacities prior to noticeable declines in
levels production capacity.
Annual demands A demand of 4,000 acft/yr is 80% of the combined CRMWA
Develop Phase I Non -Potable Reuse exceed 4,000 2031 and City annual supplies. Note that 4,000 acft/yr exceeds
acft/yr the 2070 Expected Demands projection and this project
would only be needed under the High Demands projection.
Implement when demands exceed 80% of available annual
Annual demand i supply. Could be implemented with discharge into the
Develop Phase 11 Potable Reuse exceed 4,400 0 ; terminal storage reservoir. Note that 4,400 acft/yr exceeds
acft/yr the 2070 Expected Demands protection and this project
would only be needed under the High Demands projection.
BMP = best management practice-, acft/yr = acre-feet per year, CRMWA = Canadian River Municipal Water Authority
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6.4 Implementation of the Long -Range Water Supply Plan
6.4.1 Impacts of the Plan on Utility Finances
The strategies recommended in the LRWSP represent a substantial cost to be borne by the
City's water customers. One method for determining the impact of the plan on customer costs is
to divide the annual costs of the strategies by the projected annual water demands and
determine the annual costs of the strategies per 1,000 gallons of future demand. As costs
increase as strategies are implemented, unit costs are somewhat mitigated as demands also
increase. The cost per 1,000 gallons to implement the plan are shown in Figure 20 under the
High Demands projection.
Implementing the strategies recommended in the LRWSP will contribute a maximum of $4.05
per 1,000 gallons to the average cost of water.
$4 50
0
$3 00
0
m
o $2 50
0
0
a: $2 00
a
m
$150
m
�2 $100
0
U
$0 50
2025 2030 2035 2040 2045 2050 2055 2060 2065 2070
Year
Figure 20. Cost to implement the Long -Range Water Supply Plan per 1,000 gallons of future demands (High
Demands projection.
Figure 21 shows the contribution of each strategy to the cost per 1,000 gallons under the High
Demands projection.
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$4 50
$4 00
c
Q $3.50
0
c $3 00
0
m
rn
o $2 50
0
n $2 00
ai
$150
m
rn
o $1.00
W
0
U
$0.50
•Cons at,.r •Ten^. ai Storage Rese—I •AquAer Storage and Recovery ■Phase i No, -Potable Reuse •Phase 1! Potable Reuse III
I
2025 2030 2035 2040 2045 2050 2055 2060 2065 2070
Year
Figure 21. Contribution of individual strategies to cost to implement the Long -Range Water Supply Plan.
6.4.2 Recommended Future Actions
6.4.2.1 COORDINATION WITH TWDB FOR FUNDING
The projects in this LRWSP represent a considerable investment by the City of Plainview. The
TWDB has a number of funding programs available that include low -interest loans, grants, and
loans with some principal forgiveness. Coordination with the TWDB should be started well in
advance of needing the funds because some of the programs can take over a year to secure
funding.
6.4.2.2 COORDINATION WITH THE LLANO-ESTACADO REGIONAL WATER PLANNING GROUP
To be eligible for certain types of low-cost funding from the TWDB, a project must be identified
as a recommended water management strategy in the applicable regional and state water
plans. The City should coordinate with the Llano -Estacado Regional Water Planning Group so
that each of the projects identified in the LRWSP is included in the regional water plan.
6.4.2.3 WATER CONSERVATION
The City Council should adopt the updated Water Conservation and Drought Contingency Plan
as an ordinance in 2021/2022. Plans for implementing the rebate programs should be finalized
and the programs kicked off in early 2022. The outside watering restrictions should be well -
publicized on the City's website and in appropriate media outlets and on social media prior to
March 2022.
6.4.2.4 ACTIVELY MANAGE WELLFIELD
City staff should prioritize reducing dependance on the City's wellfield as a routine supply and
plan to use the wellfield during high demand conditions only (May through September). CRMWA
should be notified of the City's anticipated water needs for 2022 so that CRMWA can make the
necessary arrangements to allocate the appropriate annual supply to Plainview. City staff
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City of Plainview
should develop a plan for monitoring long-term static water levels in all City -owned wells, and
annually review those water level changes to quantify long-term declines.
6.4.2.5 TERMINAL STORAGE RESERVOIR
A preliminary engineering study should be conducted which should include a siting study and
confirmation of the design parameters for the reservoir, including the size most advantageous to
the City's goals. Land should then be acquired for the project. The reservoir embankment
design should be optimized to minimize earthwork costs while maintaining the target storage.
Following preliminary design, final design, permitting, and construction should be completed.
6.4.2.6 AQUIFER STORAGE AND RECOVERY
Development of the ASR system can be accomplished in a phased manner with development of
a single ASR well at a time. The City's first step in this process should be to complete a more
detailed hydrogeology study to identify those areas within the City's existing wellfield best suited
for operation of an ASR well and confirm the compatibility of the City's existing potable water
with the aquifer medium in which the water will be stored. The City should then conduct a pilot
study with a smaller pilot well to confirm the suitability of the concept.
6.4.2.7 PHASE 1 NON -POTABLE REUSE
Specific customers for the non -potable reuse supply should be identified and their required
water demands confirmed. Commitments to purchase the supply should be obtained and the
preliminary engineering design completed to develop an operational plan for the reuse system
and size the system's components. A "210" reuse authorization will need to be obtained from
the TCEQ. This will require that the City be able to provide appropriate quality effluent from the
City's Water Reclamation Plant and any treatment improvements implemented prior to delivery
of the supply to the end user. Final engineering design, permitting, and construction of the reuse
system should then be completed.
6.4.2.8 PHASE II POTABLE REUSE
TCEQ will require a pilot study prior to regulatory approval and for determining design values for
the treatment technologies. Treatment requirements for any reclaimed water as a drinking water
source may consider the pretreatment program, influent wastewater quality, vulnerability
assessment of the collection system, results of effluent quality sampling/monitoring data, and
wastewater treatment process.
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