Sump / Tank

Storage capacity

Length (rectangular)Width (rectangular)Inner diameter (circular — leave 0 if rectangular)DepthNo. of such tanksnos

Capacity

litres

Shape: Rectangular
Volume: 0 m³ (1 tank)
Per tank: 0 L
Usable (150 mm free board): 0 L
200 L drums: 0 nos
Days for a family of 4: 0 days

Mark

Quantitynos

How we got this

1
Internal volume
V = L × W × D × No. of such tanks
= 0 × 0 × 0 × 1
= 0 m³
Rectangular tank — enter an inner diameter instead to switch to a circular tank.
2
Convert to litres
1 m³ = 1000 litres
= 0 × 1000
= 0 litres
3
Usable capacity
Usable = Plan area × (D − 0.15 m free board)
= 0 m² × 0
= 0 litres
4
Storage in days
Days = Usable / (4 persons × 150 L)
= 0 / 600
= 0 days

The theory behind it

Method used: Volumetric capacity method — 1 m³ = 1000 litres, IS 3370 water-retaining structures

Capacity = internal length × width × depth of water, and 1 m³ = 1000 litres. Always measure inside faces — using outside dimensions on a 200 mm thick sump over-states capacity by a fifth.

Assumptions used

•Internal (clear) dimensions used.
•Free board of 150–200 mm should be deducted from the depth for the usable volume.
•Domestic demand 135 litres per person per day (NBC).
•Family of 4 assumed at 150 L/head/day = 600 L/day.

Codes & references

NBC 2016, Part 9 — Water supply, 135 lpcd
IS 3370 — Concrete structures for storage of liquids

History

Estimates for guidance only. Confirm quantities with your site engineer.