DDW-2025-000964

Utah Department of Environmental Quality
Division of Drinking Water
Minimum Sizing Standards
Date Standard Effective: Wed Jan 29 08:02:32 MST 2025
Peak Day Source Demand per ERC (gal/day): 1,649
Average Annual Demand per ERC (gal/day): 186,399
Equalization Storage per ERC (gal/day): 511
ROCKY RIDGE TOWN WATER SYSTEM PWS ID: UTAH12019
Admin Name: CASEY J REYNOLDS
Address: 195 E. Mountain Ridge Rd
City, State, Zip: Rocky Ridge, UT 84645
Phone: [phone]
Email: [e-mail]
System Type: Community
Population: 1,297
MINIMUM SIZING STANDARD
MINIMUM SIZING STANDARD CALCULATIONS VARIABILITY
Data from these reporting years: 2021, 2022, 2023
Peak Day Source Demand per ERC (gal/day): 1,649
Average Annual Demand per ERC (gal/year): 186,399
Equalization Storage per ERC (gal): 511
x
x
x
(1 + 0.0)
(1 + 0.0)
(1 + 0.0)
=
=
=
1,649
186,399
511
DWRi WATER USE DATA REPORTED
Equalization per ERC (gal): 511
Existing Storage (gal): 600,000
ERCs: 181
Required Storage w/o Fire Flow: 92,491
Required Fire Storage (gal): 120,000
Required Storage w/Fire (gal): 212,491
Storage Deficiency: 0
Storage Deficiency (%): 0.0
No Storage Deficiency
Peak Day Source Demand per ERC (gpm): 1.15
Existing Source Capacity (gpm): 1,326
ERCs: 181
Required Source Capacity (gpm): 208
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/day)
Equaliza
tion
Storage
per ERC
(gal/day)
OP
Days
2023 244,388 30,515,946.15 181 1,350 168,597 462 365
2022 276,973 30,532,238.7 168 1,649 181,740 498 365
2021 202,027 30,196,612.17 162 1,247 186,399 511 365
Variability:0.117 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
2023 190,149 1,051 1.29
2022 180,374 1,074 1.54
2021 197,402 1,219 1.02
CAPACITY CALCULATIONS FOR STORAGE
CAPACITY CALCULATIONS FOR SOURCES
SYSTEM STORAGE AND SOURCE INVENTORY
Storage ID Storage Name Effective Volume (GAL)
ST001 100,000 GALLON TANK 100,000
ST002 500,000 GALLON TANK 500,000
Storage Totals: 600,000 GAL
Source ID Source Name Flow Rate (GPM)
WS001 WELL # 1 SOUTH 95
WS002 WELL # 2 NORTH 165
WS003 WELL #3 1,066
Source Totals: 1,326 GPM