How to design and construct a septic tank

In this construction video tutorial, one can briefly learn the methods which are necessary to design and construct a septic tank.

One will be familiar with the various standard dimensions of a septic tank by studying them from a plan.

Some useful information on septic tank design

The capacity of septic tank is based on the number of users and intermission of sludge removal. Usually sludge should have been discharged every 2 years. The liquid capacity of tank is assumed as 130 liters to 70 liters per head. For small number of users 130ltr per head is assumed.

A septic tank is normally constructed with brick wall in which cement mortar [not below 20cm (9 inch)] thick and the foundation floor is made of cement concrete with 1:2:4 ratios.

Both inner and outer faces of the wall and top of the floor are plastered with cement mortar in 1:3 mix ratio by maintaining lowest thickness of 12mm (one-half inch).

All inner corners of septic tank are rounded. Water proofing agent like Impermo, Cem-seal or Accoproof etc. should have been included to the mortar at the rate of 2% of the cement weight. Water proofing agent should also be included in equivalent ratio to the concrete for building up the floor of the tank.

To collect and discharge of the sludge properly, the floor of septic tank is provided with a slope of 1:10 to 1:20 towards the inlet side. It signifies that floor of the outlet side must remain on the higher elevation as compared to the floor at inlet side. Watch the following video tutorial to learn the detail process for design and calculation.

To learn the entire process, go through the following video tutorial.

Video Source: Civil Study