DDW-2025-002376

Utah Department of Environmental Quality
Division of Drinking Water
Minimum Sizing Standards
Date Standard Effective: Wed Mar 12 15:49:58 MDT 2025
Peak Day Source Demand per ERC (gal/day): 822
Average Annual Demand per ERC (gal/year): 179,318
Equalization Storage per ERC (gal): 491
WASHINGTON CITY PWS ID: UTAH27021
Admin Name: LESTER CARL DALTON
Address: 1305 East Washington Dam Rd
City, State, Zip: Washington, UT 84780
Phone: [phone]
Email: [e-mail]
System Type: Community
Population: 38,015
MINIMUM SIZING STANDARD
MINIMUM SIZING STANDARD CALCULATIONS VARIABILITY
Data from these reporting years: 2022, 2023, 2024
Peak Day Source Demand per ERC (gal/day): 822
Average Annual Demand per ERC (gal/year): 179,318
Equalization Storage per ERC (gal): 491
x
x
x
(1 + 0.0)
(1 + 0.0)
(1 + 0.0)
=
=
=
822
179,318
491
DWRi WATER USE DATA REPORTED
Equalization per ERC (gal): 491
Existing Storage (gal): 12,128,932
ERCs: 19,999
Required Storage w/o Fire Flow: 9,819,509
Required Fire Storage (gal): 360,000
Required Storage w/Fire (gal): 10,179,509
Storage Deficiency: 0
Storage Deficiency (%): 0.0
No Storage Deficiency
Peak Day Source Demand per ERC (gpm):
0.57 Existing Source Capacity (gpm): 12,806
ERCs: 19,999
Required Source Capacity (gpm): 11,399
Source Deficiency: 0
Source Deficiency (%): 0.0
No Source Deficiency
Year Peak
Day
Source
Demand
(gal/day)
Average
Annual
Demand
(gallons)
ERCs Peak
Demand
per ERC
(gal/day)
Avg
Annual
Demand
per ERC
(gal/year
Equaliza
tion
Storage
per ERC
(gal)
OP
Days
2024 14,549,247 3,101,397,681.84 19,999 728 155,082 424 366
2023 13,405,510 2,779,574,200.2 17,044 787 163,083 447 365
2022 13,636,864 2,975,586,610.74 16,594 822 179,318 491 365
Variability:0.205 0.0 0.0 0.0
Year Peak Month Average
(gal/day)
Peak Month Average
per ERD (gal/day)
Ratio of PD/ERC to
Peak Month Avg/ERC
2024 12,867,225 643 1.13
2023 11,926,041 700 1.12
2022 12,236,756 737 1.11
CAPACITY CALCULATIONS FOR STORAGE
CAPACITY CALCULATIONS FOR SOURCES
SYSTEM STORAGE AND SOURCE INVENTORY
Storage ID Storage Name Effective Volume (GAL)
ST001 RED CLIFF TANK 1 MG 1,000,000
ST002 RED CLIFF TANK 2.3 MG 2,300,000
ST003 GRAPE VINE TANK 1 MG 1,000,000
ST004 WARNER VALLEY TANK 1,000,000
ST005 WASHINGTON DAM RD TANK 2 MG 2,000,000
ST006 WATER TREATMENT PLANT TANK 500K 328,932
ST007 RED CLIFFS 2 MG TANK 2,000,000
ST009 LONG VALLEY 2.5 MG TANK 2,500,000
Storage Totals: 12,128,932 GAL
Source ID Source Name Flow Rate (GPM)
WS007 WELL 2 600
WS008 WELL 3 180
WS009 WELL 4 650
WS010 WELL 5 750
WS011 WELL 6 600
WS012 GRAPEVINE WELL 1 180
WS013 GRAPEVINE WELL 2 90
TP014 WASHINGTON CITY MEMBRANE FILTRATION PLAN
WS015 UTAH27094 WCWCD-QUAIL LAKE 7,267
RW003 QUAIL CREEK SAND HOLLOW VIRGIN RIVER
WS016 UTAH27073 WASHINGTON CO WCD-SAND HOLLOW
WS017 GRAPEVINE #3 80
WS018 GRAPEVINE #4 100
WS019 GRAPEVINE #5 93
WS020 GRAPEVINE #6 133
Source Totals: 12,806 GPM
2,083