DDW-2025-001176

West Haven Capacity Calculation.xlsx Page 1 of 2/3/2025
Division of Drinking Water — Water System Capacity Calculation Sheet (Last Update 3/30/2017)
*Enter the green cells only*
System Name West Haven Special Service District System Number Utah 29120
1.1 Indoor Water Use
Number of residential connections - - - - - - - - - - -- - - - - - - - - - - - - - - - - - -- - - - - - - - -373
Number of other connections - - - 2 ERCs of other connections 2.0 (Example: water use of 2 factories
equals to water use of 55 homes.)
Total Equivalent Residential Connections (ERCs)375.0
MIN. REQUIREMENTS FOR INDOOR WATER USE
Source Storage
gpd/ERC Total (gpm)Gallons/ERC Total (gallons)
800 208.3)400 (150,000)
1.2 Outdoor Water Use
Is the drinking water used for outdoor irrigation?
Residential ERCs using drinking water for irrigation - - - - - - - - - - - - > > >180
Percentage of Residential ERCs using DW for irrigation - - - - - - - - - - - - > > >48%Map Zones
Average irrigated acreage per residential connection - - - - - - - - - - - - > > >0.10 1
Total irrigated acreage of other connections (park, school, etc.)- - - - - - - - - - - - > > >2.00 2
(Enter notes here regarding whether and what % of
irrigation water is supplied by PWS.)
Irrigation zone 1 3
4
5
MIN. REQUIREMENTS FOR IRRIGATION USE 6
Source Storage
gpd/ERC Total (gpm)Gallons/ERC Total (gallons)
325 45.2 178 35,640
1.3 Fire Flow Water Use
Does the water system provide fire protection?
Maximum fire flow demand (in gpm) for water system or pressure zone 1,455
Maximum fire suppression duration (in hours) for water system or pressure zone 1
Required Fire Suppression Storage (in gallons) - - - - - - - - - - - - - - - - - - - - > > >87,300
(*Verify req'd fire flow and duration with local fire code officials.* Enter notes here, e.g. fire
official contact info or comments.)
2. Summary of Water System Capacity Requirements
MINIMUM REQUIREMENTS FOR WATER SYSTEM
Source (indoor + outdoor)Storage (indoor + outdoor + fire)
gpd/ERC Total (gpm)Gallons/ERC Total (gallons)
1,125 253.5 578 272,940
2.1 Does this system have adequate source capacity (per R309-510-7)?
This source capacity assessment is a general overall system calculation. It may not reflect the variations in individual areas or pressure zones.
Required Source Capacity 253.5 gpm
Existing Source Capacity 3,200.0 gpm
Source Capacity Deficit None gpm
Existing % of Total Req'd 1262.2%
2.2 Does this system have adequate storage capacity (per R309-510-8)?
This storage capacity assessment is a general overall system calculation. It may not reflect the variations in individual areas or pressure zones.
Total Required Storage 272,940 gal
Existing Storage Capacity 1,000,000 gal
Storage Capacity Deficit None gal
Required Fire Storage 87,300 gal
Is storage deficiency solely due to
fire storage?Not Applicable
Existing % of Total Req'd 366.4%
West Haven Capacity Calculation.xlsx Page 2 of 2/3/2025
3. Transient PWS Indoor Water Use — ERC Calcuation (See R309-510, Tables 510-1, 2, & 4 for other facility types.)
MINIMUM REQUIREMENTS FOR INDOOR USE
Source Storage
Facility Type GPD/person*GPD/site or pad Gallons/person Gallon/site
or pad ERC/site or pad Total # of sites/pads ERCs
Modern Recreation Camp 60 0 30 0 0.00 0 0.0
Semi-Developed Camp w/ flush toilets 20 0 10 0 0.00 0 0.0
Semi-Developed Camp w/o flush toilets 5 0 2.5 0 0.00 0 0.0
RV Park N/A 100 N/A 50 0.13 0 0.0
Number of people per camp site 0
Source
(GPD/vehicle)
Storage (Gal.
/vehicle)
ERC/1000
vehicles served
Vehicles
served/day ERCs
Roadway Rest Stop w/ flushometer valves 7 3.5 8.8 0 0.0
4. Data Input for Calculating ERCs, Source and Storage 4.2 Summary - Existing Sources (enter in green cells below)
West Haven Special Service District Total Existing Source Capacity (in gpm)3,200
4.1 Projected ERCs Calculation (optional)WS001 Roy 29016 10"2000
Total Projected ERCs 447 WS001 Roy 29016 6"1200
Existing Residential Connections 400
Obligated Future ERCs (enter below)47
47 Future residential units
Maximum ERCs (assuming indoor use only)5760
4.3 Summary - Existing Storage Tanks (enter below)
Total Existing Storage Cap. (in gallons)1,000,000
WS001 Roy PWS#29016 1,000,000
WS001 Roy City consective connection with garanteed 1,000,000 storage.