What Should Be The Septic Tank Size and Dimension
I will discuss about septic tank size, shape and dimensions in this article. The shape of the tank influences the velocity of waste water flowing through the tank as well as the depth of sludge accumulation. If the septic tank dimension is too deep then the other tank dimensions will be too small, which might result in short circuiting of the inlet and outlet flow, thereby shortening the detention time. Conversely if the septic tank dimension is too shallow, the clear space depth will be too small for the detention of the settle-able solids. However, tanks with greater surface area and of reasonable depth are preferred, because increased liquid surface area increases surge storage capacity. These surges of flow through the tank diminish as the surface area increases.
Septic Tank Shape
A rectangular septic tank has been reported to be better than a square septic tank, while long narrow tanks are more satisfactory. Tanks of cylindrical shape of appropriate septic tank sizes are also reported to be satisfactory in some cases, and are less costly to install. However, a rectangular shape for a single compartment tank is most favored with a length three times its width.
Table of Septic Tank Sizes, Dimensions & Weights
Below is a table provided with columns of septic tank sizes, septic tank dimensions, relative tank weights & covered soil.
| Septic Tank Size | Dimensions | Weight (lbs) | Anchor Weight (lbs) | Soil Cover (in) |
|---|---|---|---|---|
| 5000 gal | 204″L x 96″W x 93″H | 41,400 | 30,850 | 24 |
| 3000 gal | 165″L x 92″W x 76″H | 20,300 | 23,320 | 23 |
| 2600 gal | 147″L x 90″W x 73″H | 18,100 | 20,625 | 24 |
| 2000 gal | 162″L x 78″W x 64″H | 16,100 | 15,675 | 19 |
| 1600 gal | 145″L x 78″W x 61″H | 14,000 | 11,270 | 16 |
| 1200 gal | 111″L x 78″W x 61″H | 11,400 | 9,532 | 17 |
| 1000 gal Low Profile | 120″L x 67″W x 57″H | 9,500 | 8,705 | 17 |
| 1000 gal Heavy Duty | 96″L x 78″W x 61″H | 9,200 | 8,945 | 18 |
| 800 gal | 96″L x 67″W x 57″H | 8,000 | 6,560 | 16 |
| 600 gal | 78″L x 56″W x 60″H | 6,600 | 3,810 | 14 |
| 1600/1400 gal | 174″L x 90″W x 73″H | 23,000 | 22,410 | 22 |
| 1250/750 gal | 162″L x 78″W x 64″H | 16,400 | 15,725 | 19 |
| 1000/600 gal | 145″L x 78″W x 61″H | 14,700 | 12,705 | 17 |
You can check my other posts on Ventilated Pit Latrines and Simple Pit Latrines.