Archive · 1 Oct 2026
Maharashtra to Test Desilting Before Mumbai Reservoir Cleanup
The Maharashtra government wants to learn the best way to remove mud and sand from reservoirs.
It will first test these methods at seven irrigation projects.
The results may help decide whether Mumbai’s drinking-water reservoirs should also be cleaned.
Mumbai’s water reservoirs have lost some storage space because of silt buildup.
Surveys found the largest recorded declines at Vihar and Tulsi.
However, MERI said silt at Tansa had not reduced its water-supply ability.
Mumbai currently has enough stored water until May 17, 2027.
A 10% water cut may continue until the next monsoon.
Maharashtra will test desilting methods at seven major irrigation projects.
Pilot results will guide decisions on cleaning Mumbai’s seven water-supply reservoirs.
Surveys found storage-capacity declines of 16.42% at Vihar and 14.98% at Tulsi.
Mumbai’s lakes held 13.94 lakh million litres, or 96% capacity, on September 30.
The city’s 10% water cut is likely to continue until the next monsoon.
- Who
- The Maharashtra government, the Brihanmumbai Municipal Corporation, municipal corporators, and agencies including MERI and the Central Water Commission are involved.
- What
- A pilot programme will test desilting at seven irrigation projects before decisions are made about desilting Mumbai’s drinking-water reservoirs.
- When
- The announcement and water-stock figures were reported on September 30, 2026; the pilot’s implementation date was not specified.
- Where
- The pilot will cover projects in Solapur, Nashik, Bhandara, Ahilyanagar, Chhatrapati Sambhajinagar, Jalgaon, and Satara, while the possible follow-up concerns Mumbai’s reservoirs.
- Why
- The pilot is intended to assess desilting methods and determine whether cleaning Mumbai’s reservoirs is technically and economically justified amid declining storage capacity.
Regular Desilting Advocates
Technical and Economic Review
How often reservoirs should be cleaned
Regular Desilting Advocates
Standing Committee Chairman Prabhakar Shinde supports desilting Mumbai’s reservoirs every five to 10 years, preferably before the monsoon, because soil, leaf litter, and waste may reduce storage and affect summer supply.
Technical and Economic Review
The BMC administration is relying on pilot results, silt surveys, CWC guidance, and consultant assessments before deciding whether desilting is necessary.
Immediate action at affected reservoirs
Regular Desilting Advocates
Corporators’ demand reflects concern that silt accumulation is reducing reservoir capacity and could affect Mumbai’s water supply.
Technical and Economic Review
MERI reported that silt at Tansa had not affected its water-supply capacity, while CWC guidance indicates that reservoirs with annual storage losses around 0.2% generally require monitoring rather than immediate desilting.
- Pilot projects
- Ujani, Girna, Gosikhurd, Mula, Jayakwadi, Hatnur, and Koyna
- Mumbai storage status
- 13.94 lakh million litres, equal to 96% capacity, on September 30
- Water availability
- Stored water was projected to meet Mumbai’s needs until May 17, 2027
- Current supply and demand
- Supply is 4,100 MLD against demand of 4,600 MLD
- Largest recorded decline
- Vihar reservoir storage capacity has declined by 16.42%
- Water restriction
- A 10% water cut imposed from May 15 is likely to continue until the next monsoon