Septic tanks shall have not less than two compartments. The inlet compartment shall be not less than two-thirds of the total capacity of the tank, not less than a 500-gallon (1893 L) liquid capacity and not less than 3 feet (914 mm) wide and 5 feet (1524 mm) long. The secondary compartment of a septic tank shall have not less than a capacity of 250 gallons (946 L) and not more than one-third of the total capacity. The secondary compartment of septic tanks having a capacity more than 1,500 gallons (5678 L) shall be not less than 5 feet (1524 mm) long.
The liquid depth shall be not less than 30 inches (762 mm) and a maximum average of 6 feet (1829 mm). The total depth shall be not less than 8 inches (203 mm) greater than the liquid depth.
Rectangular tanks shall be constructed with the longest dimensions parallel to the direction of the flow.
Cylindrical tanks shall be not less than 48 inches (1219 mm) in diameter.
For buildings, the liquid capacity shall be increased above the 750-gallon (2839 L) minimum as established in Table 802.7.1. In buildings with kitchen or laundry waste, the tank capacity shall be increased to receive the anticipated volume for a 24-hour period from the kitchen or laundry or both. The liquid capacities established in Table 802.7.2 do not include employees.
Exception: One- or two-family dwellings.
ADDITIONAL CAPACITY FOR OTHER BUILDINGS
|BUILDING CLASSIFICATION||CAPACITY (gallons)|
|Apartment buildings (per bedroom—includes automatic clothes washer)||150|
|Assembly halls (per person—no kitchen)||2|
|Bars and cocktail lounges (per patron space)||9|
|Beauty salons (per station—includes customers)||140|
|Bowling centers (per lane)||125|
|Bowling centers with bar (per lane)||225|
|Camp, day use only—no meals served (per person)||15|
|Campgrounds and camping resorts (per camp space)||100|
|Campground sanitary dump stations (per camp space) (omit camp spaces with sewer connection)||5|
|Camps, day and night (per person)||40|
|Car washes (per car handwash)||50|
|Catch basins—such as for garages and motor-fuel-dispensing facilities (per basin)||100|
|Catch basins—truck washing (per truck)||100|
|Places of religious worship—no kitchen (per person)||3|
|Places of religious worship—with kitchen (per person)||7.5|
|Condominiums (per bedroom—includes automatic clothes washer)||150|
|Dance halls (per person)||3|
|Dining halls—kitchen and toilet waste—with dishwasher, food waste grinder or both (per meal served)||11|
|Dining halls—kitchen waste only (per meal served)||3|
|Drive-in restaurants—all paper service (per car space)||15|
|Drive-in restaurants—all paper service, inside seating (per seat)||15|
|Drive-in theaters (per car space)||5|
|Employees—in all buildings, per employee—total all shifts||20|
|Floor drains (per drain)||50|
|Hospitals (per bed space)||200|
|Hotels or motels and tourist rooming houses||100|
|Labor camps, central bathhouses (per employee)||30|
|Medical office buildings, clinics and dental offices|
Doctors, nurses, medical staff (per person)Office personnel (per person)
Patients (per person)
|Mobile home parks, homes with bathroom groups (per site)||300|
|Nursing and rest homes—without laundry (per bed space)||100|
|Outdoor sports facilities (toilet waste only—per person)||5|
|Parks, toilet waste (per person—75 persons per acre)||5|
|Parks, with showers and toilet waste (per person—75 persons per acre)||10|
|Restaurants—dishwasher or food waste grinder or both (per seat)||3|
|Restaurants—kitchen and toilet wastes (per seating space)||30|
|Restaurants—kitchen waste only—without dishwasher and food waste grinder (per seat)||9|
|Restaurants—toilet waste only (per seat)||21|
|Restaurants (24-hour)—dishwasher or food waste grinder (per seat)||6|
|Restaurants (24 hour)—kitchen and toilet waste (per seating space)||60|
|Schools (per classroom—25 pupils per classroom)||450|
|Schools with meals served (per classroom—25 pupils per classroom)||600|
|Schools with meals served and showers provided (per classroom)||750|
|Self-service laundries (toilet waste only, per machine)|
Automatic clothes washers—such as for apartments and service buildings, (per machine)
|Showers—public (per shower taken)||15|
|Swimming pool bathhouses (per person)||10|
For SI: 1 gallon = 3.785 L.
Septic and other treatment tanks shall be located with a horizontal distance not less than specified in Table 802.8 between various elements. Tanks installed in ground water shall be securely anchored. A 3-inch-thick (76 mm) compacted bedding shall be provided for all septic and other treatment tank installations. The bedding material shall be sand, gravel, granite, limerock or other noncorrosive materials of such size that the material passes through a 0.5-inch (12.7 mm) screen.
The working capacity of the dosing or pumping chamber shall be sized to permit automatic discharge of the total daily sewage flow with discharge occurring not more than four times per 24 hours. Minimum capacity of a dosing chamber shall be 500 gallons (1893 L) and a space shall be provided between the bottom of the pump and floor of the dosing or pumping chamber. A dosing chamber shall have a 1-day holding capacity located above the high-water alarm for one- and two-family dwellings based on 100 gallons (379 L) per day per bedroom, or in the case of other buildings, in accordance with Section 802.7. Minimum pump chamber sizes are indicated for one- and two-family dwellings in Table 802.11.1. Where the total developed length of distribution piping exceeds 1,000 feet (305 m), the dosing or pumping chamber shall have two siphons or pumps dosing alternately and serving one-half of the soil absorption system.
PUMP CHAMBER SIZES
|NUMBER OF BEDROOMS||MINIMUM PUMPING CHAMBER SIZE|
For SI: 1 gallon = 3.785 L.
The minimum liquid capacity of a holding tank for one- and two-family dwellings shall be in accordance with Table 805.2. Other buildings shall have a minimum 5-day holding capacity, but not less than 2,000 gallons (7570 L). Sizing shall be in accordance with Table 802.7.2. Not more than four holding tanks shall be installed in series.