13.20.300 Design flow.
A. The average design flow shall be used to size soil treatment systems. The estimated average design flow for any dwelling shall provide for at least 3 bedrooms. For multi-family dwellings, the average design flow shall consist of the sum of the average design flows for each individual unit. These design flows are listed in Table 1b:
|
Number of Bedrooms |
Flow Volume (gpd) |
|
|---|---|---|
|
Class I |
Class II |
|
|
3 |
360 |
450 |
|
4 |
480 |
600 |
|
5 |
600 |
750 |
|
6 |
720 |
900 |
B. These design flows are based on the following formulas:
1. Classification I. Classification I dwellings correspond with the minimum standards allowed by ARSD § 74:53:01:31.
2. Classification II. Classification II dwellings are those with more than 2 of the following water-use appliances: automatic washer, dishwasher, water conditioning unit, whirlpool bath, multi head showers, or self-cleaning humidifier in furnace. The average design flow for Classification II dwellings is determined by multiplying the number of bedrooms by 150.