Rainwater harvesting cost · Tamil Nadu

Rainwater harvesting cost in Thoothukudi

₹1.1 lakh to ₹1.7 lakhfor a house with a 100 m² roof, GST included

That buys a filter on the downpipe and a recharge pit with a 120 ft recharge bore, which sends about 80,580 litres of Thoothukudi's rain back into the ground every year. The bore is the biggest cost, so the final price depends on how deep the water-bearing layer is under your plot.

Cost by building size in Thoothukudi

Each recharge pit (2 × 2 × 2.5 m with a 120 ft bore) takes the water from a 25 mm downpour on about 280 m² of roof. Bigger roofs need more pits.

Building	Roof area	Recharge pits	Water put back a year	Cost
Independent house	100 m² (1,076 sq ft)	1	80,580 L	₹1.1 lakh to ₹1.7 lakh
Large house or villa	250 m² (2,691 sq ft)	1	2,01,450 L	₹1.1 lakh to ₹1.7 lakh
Small apartment block or office	600 m² (6,458 sq ft)	3	4,83,480 L	₹3.1 lakh to ₹4.8 lakh
Housing society, school or factory	2,000 m² (21,528 sq ft)	8	16,11,600 L	₹8 lakh to ₹12 lakh

How the bore depth changes the price

The same house with a 100 m² roof, with the recharge bore drilled to different depths. The depth is set on site from the soil and water levels.

₹87,000 to ₹1.4 lakhwith a 60 ft bore

₹1.1 lakh to ₹1.7 lakhwith a 120 ft bore

₹1.4 lakh to ₹2.2 lakhwith a 200 ft bore

What is included

Item	Rate before GST
Recharge pit 2 × 2 × 2.5 m: digging, brick lining, concrete base and cover with manhole	₹28,000 to ₹38,000 each
Filter media in the pit: boulders, gravel and coarse sand	₹8,000 to ₹12,000 each
150 mm recharge bore with slotted PVC pipe	₹300 to ₹500 a foot
Filter chamber on the roof downpipe (gravel, charcoal and sand)	₹12,000 to ₹20,000 each
Downpipe connections, mesh guards, first-flush diverter and overflow	₹8,000 to ₹15,000 per building

GST at 18% is added on top. A storage tank for reusing the water, paved-area drains and silt traps cost extra. Prices are TerraSetu's estimates for 2026 and are confirmed after a site survey.

Is it worth it in Thoothukudi?

28%Safe

Thoothukudi pumps out 28% of the groundwater that can safely be taken out each year (2025, Central Ground Water Board), rated safe. Groundwater is within safe limits, and recharge keeps it that way as the city grows. A house system puts back about 8 water tankers of 10,000 litres a year.

Groundwater level in Thoothukudi Rainfall in Thoothukudi Water quality in Thoothukudi

Rainwater harvesting rules in Tamil Nadu

Tamil Nadu requires rainwater harvesting in every building, new and existing, public and private, with no size threshold. This rule dates from 2003. If an owner doesn't install it, the local body can install it and recover the cost like property tax, and the water connection can be cut until it is in place. In Chennai, Metrowater gives no new water or sewer connection without RWH.

Rules in Tamil Nadu

Get a quote in Thoothukudi

TerraSetu measures your roof, checks the soil and water level, and gives a fixed price for the system.

Get a site survey

Frequently asked questions

What is the cost of rainwater harvesting in Thoothukudi?

A rooftop rainwater harvesting system with a recharge pit for a house with a 100 m² (1,076 sq ft) roof costs about ₹1.1 lakh to ₹1.7 lakh in Thoothukudi, including GST, with a 120 ft recharge bore. The bore depth makes the biggest difference to the price; larger buildings need more pits.

How much water does rainwater harvesting save in Thoothukudi?

Thoothukudi gets about 948 mm of rain a year, so a 100 m² roof sends about 80,580 litres into the ground each year, roughly 8 tankers of 10,000 litres.

How many recharge pits does a building need?

One 2 × 2 × 2.5 m pit with a recharge bore takes the water from a 25 mm downpour on about 280 m² of roof. A house usually needs one pit; a 2,000 m² society roof needs about eight.

How long does it take to install rainwater harvesting?

A house system usually takes three to seven days: a day or two to drill the bore, two or three to build and fill the pit, and a day to connect the downpipes and filter.