Lok Sabha Question No. 192 (STARRED), answered on 2019-07-04
Subject: Silt Accumulation in Dams/ Reservoirs/Lakes
Ministry: JAL SHAKTI
Asked by: Sudheer Gupta

## GOVERNMENT OF INDIA MINISTRY OF JAL SHAKTI, DEPARTMENT OF WATER RESOURCES, RIVER DEVELOPMENT & GANGA REJUVENATION

## LOK SABHA STARRED QUESTION NO. *192

ANSWERED ON 04 . 07.201 9

## SILT ACCUMULATION IN DAMS/ RESERVOIRS/LAK ES

## *192. SHRI SUDHEER GUPTA

Will the Minister of JAL SHAKTI be pleased to state:

- (a) whether the Government has made any survey/study about the silt accumulation dams/reservoirs/lakes across the country and if so, the details thereof along with the da reduced th e water holding capacity more than 50 per cent;
- (b) whether the Government has any proposal to remove silt therefrom and received any prop certain States for adopting new technology for the purpose;
- (c) if so, the details thereof, State - wise an d the action taken on the said proposals;
- (d) whether the Government is establishing any new mechanism using modern technology to rem from such dams/reservoirs to bring them back to their full water holding capacity and if thereof including the details of such technology; and
- (e) whether the Government has planned any silt - removal programme in the country and if so, the deta thereof, State -wise?

## ANSWER

## THE MINISTER OF JAL SHAKTI

(SHRI GAJENDRA SINGH SHEKHAWAT)

- ( a)to (e) A statement is laid on the Table of the House.

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STATEM ENT  REFERRED  TO  IN  REPLY  TO  PART S  (a)  TO  (e)  OF  LOK  SABHA STARRED  QUESTION  NO.*192  TO  BE  ANSWERED IN  LOK  SABHA ON 04.07. 2019 REGARDING ' SILT ACCUMULATION IN DAMS/ RESERVOIRS/LAKES ' RAISED BY SHRI SUDHEER GUPTA.

(a)  Central  Water  Commission  (CWC)  has  conducted  sedimentation  assessment  studies  on  2 Reservoirs  through  Hydro  Graphic  survey  and  live  storage  capacity  assessment  studies Reservoirs through Remote Sensing Technique.

As per the study, the reservoirs have experienced annual rate of siltation in live s in the range of 0 - 1% normally. Six reservoirs viz. Sanandro, Gujarat (57.33% in 30 years), B HP  (84.27%  in  30  years),  Mhaswad ,  Maharashtra  (52.04%  in  102  years),  Kundah,  Tamil  Nadu (63.07% in 22 years), Nizamsagar, Telangana (60.47% in 62 years), Chandan, Bihar (52.24% years) have experienced a loss of more than 50% of gross storage capacity. (b)  to  (e)    While  designing a  water  storage  project,  provision  for  the  Dead  Storage  is  kep accommodate  the  silt  coming  from  upstream  catchment.  The  Dead  Storage  is  so  kept  a accommodate the silt for 100 years of project life assuming a certain design rate of silta s based  on  certain  factors.  Any  deposition  of  silt  in  the  dead  storage  zone  does  not performance of the reservoir. De-siltation of dams to increase its storage capacity is primarily the responsibil owners who are generally State Gov rnments or Central/ State PSUs. -economically feasible.  Under the World Bank assisted  Dam  Rehabilitation  &  Improvement  Project  (DRIP)  there  is  a  need  based  provisi works  of  three  dams  viz.  Kundahapalam  (Tamil  Nadu),

Usually de - silting of large dams is not techno desiltation  of  dams  and  desiltation Papanasam (Tamil Nadu) and Asan Barrage (Uttarakhand) has been taken up.

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