Section Env-Dw 405.10 - Design Flow(a) Subject to (b), below, anticipated design flows for a proposed small community water system shall be based on the type of use, as specified in Table 405-1 below: Table 405-1: Anticipated Design Flows
| Type of Use | Design Flow |
| Single family homes | 150 gpd per bedroom |
| Recreational/vacation homes | 150 gpd per bedroom |
| Mobile homes | 150 gpd per bedroom |
| Apartments/Condominiums | 150 gpd per bedroom |
| Efficiency Apartments | 225 gpd per unit |
| Elderly Housing: | |
| One bedroom | 150 gpd per unit |
| 2 or more bedrooms | 100 gpd per bedroom |
| Nursing Homes | 125 gpd per bed |
| Dormitories | 100 gpd per student |
| Other Institutions | 135 gpd per bed |
(b) If the specific type of use is not listed above, the design flow shall be determined in accordance with Env-Wq 1008.(c) For small community water systems that are being expanded or upgraded, the design flow shall be determined either in accordance with (a) and (b), above, or by using historical water readings in accordance with one of the following: (1) By finding the daily average flow from water meter readings and multiplying the average by a minimum factor of 2 or a maximum factor of 3 depending on the type or frequency of the meter readings; or(2) By examining 12 months of consecutive daily water meter readings, in which case the water system's design flow shall be based on the highest daily flow noted, without application of a multiplying factor.(d) Since design flows contained in Table 405-1 and Env-Wq 1008 do not include exterior water use, for those water systems where watering lawns and garden, filling swimming pools, supplying fire protection systems such as hydrants or sprinklers, and other unusually high water demand situations are expected, additional supply capacity shall be provided.N.H. Code Admin. R. Env-Dw 405.10
(See Revision Note at part heading for Env-Dw 405) #10612, eff 6-1-14