1. (1) Peak Day Demand and Average Yearly Demand.

   1. (a) The water system's source capacity shall be able to meet the anticipated water demand on the day of highest water consumption, which is the peak day demand.
   2. (b) The water system's source capacity shall also be able to provide one year's supply of water, which is the average yearly demand.

   Sources shall legally and physically meet water demands under two conditions:

2. (2) Indoor Water Use.

   Tables 510-1 and 510-2 shall be used as the minimum sizing requirements for peak day demand and average yearly demand for indoor water use unless a public water system has obtained a reduction per R309-510-5.

   TABLE 510-1

   Source Demand for Indoor Use

   Peak Average

   Type of Connection Day Demand Yearly Demand

   Year-round use

   Residential 800 gpd/conn 146,000 gal./conn

   Equivalent

   Residential

   Connection (ERC) 800 gpd/ERC 146,000 gal./ERC

   Seasonal/Non-residential

   use

   Modern Recreation Camp 60 gpd/person (See Note 1)

   Semi-Developed Camp

3. a. with pit privies 5 gpd/person (See Note 1)

4. b. with flush toilets 20 gpd/person (See Note 1)

   1. (gpd)

      (Notes 2 and 3)

      Airports

   Hotel, Motel, and Resort 150 gpd/unit (See Note 1)

   Labor Camp 50 gpd/person (See Note 1)

   Recreational Vehicle

   Park 100 gpd/pad (See Note 1)

   Roadway Rest Stop 7 gpd/vehicle (See Note 1)

   Recreational Home

   Development

   (i.e., developments

   with limited

   water use)

   (See Note 2) 400 gpd/conn (See Note 1)

   NOTES FOR TABLE 510-1:

   Note 1. Average yearly demand shall be calculated by

   multiplying the number of days in the designated water system

   operating period by the peak day demand unless a reduction has

   been granted in accordance with R309-510-5.

   Note 2. To be considered a Recreational Home Development

   (i.e., developments with limited water use) as listed in Table

   510-1, dwellings shall not have more than 8 plumbing fixture

   units,in accordance with the state-adopted plumbing code, and

   shall not be larger than 1,000 square feet. For a new

   not-yet-constructed development to be considered as a

   development with limited water use, it must have enforceable

   restrictions in place that are enforced by the water system or

   local authority and are accepted by the Director.

   TABLE 510-2

   Source Demand for Indoor Use -

   Individual Establishments (Note 1)

   Type of Establishment Peak Day Demand

5. a. per passenger 3

6. b. per employee 15

   Boarding Houses

7. a. for each resident boarder and employee 50

8. b. for each nonresident boarders 10

   Bowling Alleys, per alley

9. a. with snack bar 100

10. b. with no snack bar 85

    Churches, per person 5

    Country Clubs

11. a. per resident member 100
12. b. per nonresident member present 25

13. c. per employee 15

    Dentist's Office

14. a. per chair 200

15. b. per staff member 35

    Doctor's Office

16. a. per patient 10

17. b. per staff member 35

    Fairgrounds, per person 1

    Fire Stations, per person

18. a. with full-time employees and food prep. 70

19. b. with no full-time employees and no food prep. 5

    Gyms

20. a. per participant 25

21. b. per spectator 4

    Hairdresser

22. a. per chair 50

23. b. per operator 35

    Hospitals, per bed space 250

    Industrial Buildings, per 8 hour shift,

    per employee (exclusive of industrial waste)

24. a. with showers 35

25. b. with no showers 15

    Launderette, per washer 580

    Movie Theaters

26. a. auditorium, per seat 5

27. b. drive-in, per car space 10

    Nursing Homes, per bed space 280

    Office Buildings and Business Establishments,

    per shift, per employee (sanitary wastes only)

28. a. with cafeteria 25

29. b. with no cafeteria 15

    Picnic Parks, per person (toilet wastes only) 5

    Restaurants

30. a. ordinary restaurants (not 24 hour service) 35 per seat
31. b. 24 hour service 50 per seat

32. c. single service customer utensils only 2 per

    customer

33. d. or, per customer served

    (includes toilet and kitchen wastes) 10

    Rooming House, per person 40

    Schools, per person

34. a. boarding 75
35. b. day, without cafeteria, gym or showers 15
36. c. day, with cafeteria, but no gym or showers 20

37. d. day, with cafeteria, gym and showers 25

    Service Stations

38. a. per vehicle served, or 10

39. b. per gas pump 250

    Skating Rink, Dance Halls, etc., per person

40. a. no kitchen wastes 10

41. b. Additional for kitchen wastes 3

    Ski Areas, per person (no kitchen wastes) 10

    Stores

42. a. per public toilet room 500

43. b. per employee 11

    1. (3) Irrigation Use.

       1. (a) Determine the location of the water system on the map entitled Irrigated Crop Consumptive Use Zones and Normal Annual Effective Precipitation, Utah as prepared by the Soil Conservation Service (available from the Division). Find the numbered zone, one through six, in which the water system is located (if located in an area described "non-arable" find nearest numbered zone).
       2. (b) Determine the net number of acres which may be irrigated.
       3. (c) Refer to Table 510-3, which assumes direct application of water to vegetation, to determine peak day demand and average yearly demand for irrigation use.

       4. (d) Consider water losses due to factors such as evaporation, irrigation delivery method, overwatering, pipe leaks, etc. Apply a safety factor to the irrigation demand in the design accordingly.

          TABLE 510-3

          Source Demand for Irrigation

          Map Zone Peak Day Demand Average Yearly Demand

          (gpm/irrigated acre) (AF/irrigated acre)

          (Note 1)

          1 2.26 1.17

          2 2.80 1.23

          3 3.39 1.66

          4 3.96 1.87

          5 4.52 2.69

          6 4.90 3.26

          NOTE FOR TABLE 510-3:

          Note 1. The average yearly demand for irrigation water

          use (in acre-feet per irrigated acre) is based on 213 days of

          irrigation, e.g., April 1 to October 31.

       If a water system provides water for irrigation, Table 510-3 shall be used to determine the peak day demand and average yearly demand for irrigation water use. The following procedure shall be used:

    2. (4) Variations in Source Yield.

       1. (a) Water systems shall consider that flow from sources may vary seasonally and yearly. Where flow varies, the number of service connections supported by a source shall be based on the minimum seasonal flow rate compared to the corresponding seasonal demand.
       2. (b) Where source capacity is limited by the capacity of treatment facilities, the maximum number of service connections shall be determined using the treatment plant design capacity instead of the source capacity.

    Swimming Pools and Bathhouses, per person 10

    (Note 4)

    Taverns, Bars, Cocktail Lounges, per seat 20

    Visitor Centers, per visitor 5

    NOTES FOR TABLE 510-2:

    Note 1. When more than one use will occur, the multiple

    uses shall be considered in determining total demand. Small

    industrial plants maintaining a cafeteria or showers and club

    houses or motels maintaining swimming pools or laundries are

    typical examples of multiple uses. Uses other than those listed

    above shall be considered in relation to established demands

    from known or similar installations.

    Note 2. Source capacity must at least equal the peak day

    demand of the system. Determine this by assuming the facility

    is used to its maximum, e.g., the physical capacity of the

    facility.

    Note 3. To determine the average day demand for

    establishments listed in Table 510-2, divide the peak day

    demand by 2, unless alternative data are accepted by the

    Director.

    Note 4. Or Peak Day Demand = 20 x (Water Area (ft2)/30) +

    Deck Area (ft2)

KEY: drinking water, minimum sizing, water conservation

Date of Last Change: July 15, 2015

Notice of Continuation: February 10, 2025

Authorizing, and Implemented or Interpreted Law: 19-4-104