Figure: 30 TAC §285.91(3)
Table III. Wastewater Usage Rate.
This table shall be used for estimating the hydraulic loading rates only. Sizing formulas are based on residential strength BOD5. Commercial/institutional facilities must pretreat their wastewater to 140 BOD5 prior to disposal unless secondary treatment quality is required. For design purposes, restaurant wastewater will be assumed to have a BOD5 of at least 1,200 mg/l after exiting the grease trap or grease interceptor.
Actual water usage data or other methods of calculating wastewater usage rates may be used by the system designer if it is accurate and acceptable to the Texas Commission on Environmental Quality or its authorized agents. If actual water use records are greater than the usage rates in this table, the system shall be designed for the higher flow.
| TYPE OF FACILITY | USAGE RATE GALLONS/DAY (Without Water Saving Devices) |
USAGE RATE GALLONS/DAY (With Water Saving Devices) |
|---|---|---|
| Single family dwelling (one or two bedrooms) - less than 1,500 square feet. Single family dwelling (three bedrooms) - less than 2,500 square feet. Single family dwelling (four bedrooms) - less than 3,500 square feet. Single family dwelling (five bedrooms) - less than 4,500 square feet. Single family dwelling (six bedrooms) - less than 5,500 square feet. Greater than 5,500 square feet, each additional 1,500 square feet or increment thereof. |
225 300 375 450 525 75 |
180 240 300 360 420 60 |
| Condominium or Townhouse (one or two bedrooms) Condominium or Townhouse (each additional bedroom) |
225 75 |
180 60 |
| Mobile home (one or two bedrooms) Mobile home (each additional bedroom) |
225 75 |
180 60 |
| Country Clubs (per member) | 25 | 20 |
| Apartment houses (per bedroom) | 125 | 100 |
| Boarding schools (per room capacity) | 50 | 40 |
| Day care centers (per child with kitchen) Day care centers (per child without kitchen) |
25 15 |
20 12 |
| Factories (per person per shift) | 15 | 12 |
| Hospitals (per bed) | 200 | 160 |
| Hotels and motels (per bed) | 75 | 60 |
| Nursing homes (per bed) | 100 | 80 |
| Laundries (self service per machine) | 250 | 200 |
| Lounges (bar and tables per person) | 10 | 8 |
| Movie Theaters (per seat) | 5 | 4 |
| Office buildings (no food or showers per occupant) Office buildings (with food service per occupant) |
5 10 |
4 8 |
| Parks (with bathhouse per person) Parks (without bathhouse per person) |
15 10 |
12 8 |
| Restaurants - minimum effluent BOD5 quality described above this table Restaurants (per seat) Restaurants (fast food per seat) |
35 15 |
28 12 |
| Schools (with food service & gym per student) Schools (without food service) |
25 15 |
20 12 |
| Service stations (per vehicle) | 10 | 8 |
| Stores (per washroom) | 200 | 160 |
| Swimming pool bathhouses (per person) | 10 | 8 |
| Travel trailer/RV parks (per space) | 50 | 40 |
| Vet clinics (per animal) | 10 | 8 |
| Construction sites (per worker) | 50 | 40 |
| Youth camps (per camper) | 30 | 24 |