What are the various State wise rooftop rainwater harvesting legislation in various Indian states?

Author: Sachin Gupta | Find me on Twitter Follow @sach_gupta

Monsoon in India is one of the oldest weather observations which happen from June to September every year. It is a major weather phenomenon because of its influence on the lives of people and their well being.

Average rainfall across various Indian states is as follows:

Sl. No.	State	Meteorological Divisions	Average annual rainfall (mm)	Average annual rainfall (ft)
1	Andaman and Nicobar Islands	Andaman and Nicobar Islands	2967	9.73
2	Arunachal Pradesh	Arunachal Pradesh	2782	9.13
3	Assam	Assam and Meghalaya	2818	9.25
4	Meghalaya	Assam and Meghalaya	2818	9.25
5	Nagaland	Nagaland, Manipur, Mizoram and Tripura	1881	6.17
6	Manipur	Nagaland, Manipur, Mizoram and Tripura	1881	6.17
7	Mizoram	Nagaland, Manipur, Mizoram and Tripura	1881	6.17
8	Tripura	Nagaland, Manipur, Mizoram and Tripura	1881	6.17
9	West Bengal	Sub-Himalayan West Bengal and Sikkim	2739	8.99
10	West Bengal	Gangetic West Bengal	1439	4.72
11	Sikkim	Sub-Himalayan West Bengal and Sikkim	2739	8.99
12	Orissa	Orissa	1489	4.89
13	Bihar	Bihar Plateau	1326	4.35
14	Bihar	Bihar Plains	1186	3.89
15	Uttar Pradesh	Uttar Pradesh	1025	3.36
16	Uttar Pradesh	Plain of West Uttar Pradesh	896	2.94
17	Uttar Pradesh	Hills of West Uttar Pradesh	1667	5.47
18	Haryana	Haryana, Chandigarh and Delhi	617	2.02
19	Delhi	Haryana, Chandigarh and Delhi	617	2.02
20	Chandigarh	Haryana, Chandigarh and Delhi	617	2.02
21	Punjab	Punjab	649	2.13
22	Himachal Pradesh	Himachal Pradesh	1251	4.10
23	Jammu and Kashmir	Jammu and Kashmir	1011	3.32
24	Rajasthan	West Rajasthan	313	1.03
25	Rajasthan	East Rajasthan	675	2.21
26	Madhya Pradesh	Madhya Pradesh	1017	3.34
27	Madhya Pradesh	East Madhya Pradesh	1338	4.39
28	Gujarat	Gujarat region	1107	3.63
29	Gujarat	Saurashtra and Kachchh	578	1.90
30	Goa	Konkan and Goa	3005	9.86
31	Maharashtra	Konkan and Goa	3005	9.86
32	Maharashtra	Madhya Maharashtra	901	2.96
33	Maharashtra	Marathwada	882	2.89
34	Maharashtra	Vidarbha	1034	3.39
35	Andhra Pradesh	Coastal Andhra Pradesh	1094	3.59
36	Andhra Pradesh	Telengana	961	3.15
37	Andhra Pradesh	Rayalaseema	680	2.23
38	Tamil Nadu	Tamil Nadu and Pondicherry	998	3.27
39	Pondicherry	Tamil Nadu and Pondicherry	998	3.27
40	Karnataka	Coastal Karnataka	3456	11.34
41	Karnataka	North Interior Karnataka	731	2.40
42	Karnataka	South Interior Karnataka	1126	3.69
43	Kerala	Kerala	3055	10.02
44	Lakshadweep	Lakshadweep	1515	4.97

As we all know, rain is the primary source of water while rivers, lakes and ground water are the secondary sources. Our daily consumption of water is fulfilled by secondary sources of water. However, these secondary sources of water are replenished by primary source of water (rainfall). Therefore, it becomes imperative for all of us to harvest this rain water in order to refill rivers, lakes, ground water.

Advantages of Water harvesting

1. Provides drinking and irrigation water.
2. Increases groundwater recharge.
3. Reduces storm water discharge, urban floods and overloading of sewage treatment plants.
4. Reduces seawater ingress in coastal areas.

An example,

Let’s take the case of Delhi; the average annual rainfall is 617 mm or 2.02 Ft. In a given area of 1 Ft by 1 Ft, the rain water that can be harvested every year will be 2.02 Cubic Feet or 57.21 liters. In other words, every household can harvest 57.21 liters of water in an area of 1 ft by 1 ft. If you have a roof of 50 ft by 20 ft, the water harvested would be 57206.4 liters.

Now, is this water harvested properly? Households, residential complexes, commercial complexes can harvest rain water by capturing runoffs from rooftops. The water thus captured can either be stored in a community water tank or allowed to go to the ground via a pipe which helps in refilling or increasing the ground water levels of a given region, thus, reducing the scarcity of water.

ACTION TAKEN BY VARIOUS STATEs / UTs / MUNICIPAL CORPORATIONS TO MAKE RAIN WATER HARVESTING (RWH)/ROOF TOP RAIN WATER HARVESTING (RWH) MANDATORY

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