Lok Sabha Question No. 2540 (UNSTARRED), answered on 2022-03-17
Subject: Salinity in Coastal Areas
Ministry: JAL SHAKTI
Asked by: Shrirang Appa Barne, Subrata Pathak, Sanjay Sadashivrao Mandlik, Manoj Kumar Tiwari, Sudheer Gupta, Sambhajirao Mane Dhairyasheel, Bidyut Baran Mahato, Prataprao  Jadhav, Ravi Kishan Shukla, Ravindra Kushawaha

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

## LOK SABHA UNSTARRED QUESTION NO. 2535

ANSWERED ON 17.03.2022

## SALINITY IN COASTAL AREAS

| 2540. SHRI SHRIRANG APPA BARNE SHRI SANJAY SADASHIVRAO MANDLIK SHRI SUDHEER GUPTA SHRI DHAIRYASHEEL SAMBHAJIRAO MANE SHRI BIDYUT BARAN MAHATO   | SHRI SUBRAT PATHAK SHRI MANOJ TIWARI SHRI PRATAPRAO JADHAV SHRI RAVINDRA KUSHWAHA SHRI RAVI KISHAN   |
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Will the Minister of JAL SHAKTI be pleased to state:

- (a) whether as per a research by the Ministry, most parts of the 1600 kilometre coastline of Gujarat is seeing salinisation of coastal ground water resulting in deterioration of its quality;
- (b) if so, the details thereof and the reasons for the same;
- (c) whether in various coastal parts of the country, ground water near coastal areas is merging with sea water making it more saline and if so, the details thereof and the the reasons therefor;
- (d)  whether  salinity  in  coastal  areas  of  the  country  is  increasing  thereby  posing  a  serious  threat  to aquaculture in the State and if so, the details thereof;
- (e) whether the Ministry is formulating any policy in this regard and if so, the details thereof; and
- (f) the corrective measures taken/being taken by the Government in this regard?

## ANSWER

## THE MINISTER OF STATE FOR JAL SHAKTI

## (SHRI BISHWESWAR TUDU)

- (a) & (b) Some parts of the 1600 kilometre coastline, i.e. in the coastal parts of Mongrol - Chorwad of Saurashtra region  of  Gujarat,  have  been  studied  by  Central  Ground  Water  Board  (CGWB).  Ingress  of  salinity  has  been observed in groundwater during the said study. The presence of salinity in ground water along coastal Gujarat may be due to various reasons viz. prevailing hydro-geological settings, presence of physiographic depression in the coastal areas, inundation of sea water in low lying areas due to tidal fluctuation etc.
- (c)  As  per  available  information,  the  details  of  various  coastal  parts  of  the  country  vis-a-vis  merging  of groundwater with seawater are given at Annexure I.
- (d) There is no specific study conducted by this department highlighting increase in  salinity in coastal areas and its effect on aquaculture.
- (e) & (f) Water being a State subject, management of groundwater water resources including tackling the salinity related  issues  is  mainly  State  subject.  Still,  Central  Government  has  taken  a  number  of  important  measures  for conservation,  management  of  ground  water  including  effective  implementation  of  rain  water  harvesting  in  the country which to some extant reduces salinity effect in groundwater which can be seen at URL:http://jalshaktidowr.gov.in/sites/default/files/Steps\_to\_control\_water\_depletion\_Feb2021.pdf.

In  addition,  National  Water  Policy  2012  talks  about  monitoring  water  use  pattern,  planning  appropriate interventions for tackling salinity, alkalinity or, similar quality problems.

Further, various measures which have been taken by the State Governments vis-à-vis salinity in groundwater, are given at Annexure II .

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## ANNEXURE REFERRED TO IN REPLY TO PARTS (c) OF UNSTARRED QUESTION NO. 2540  TO  BE  ANSWERED  IN  LOK  SABHA  ON  17.03.2022  REGARDING  'SALINITY  IN COASTAL AREAS'.

## The details of various coastal parts of the country vis-a-vis merging of groundwater with seawater as per information with CGWB

In Gujarat, in areas close to the coast, the ground water is saline even at shallow depths. The tidal ingress occurs in upper aquifers and low lying marshy lands inundated by sea water during high tides resulting into  mixing  of  saline  sea  water  with  ground  water  in  aquifers.  The  downward  seepage  in  these  areas increases ground water salinity. Further, during pre-monsoon, the water table gets lowered and a reverse hydraulic gradient is established near the coast leading to the landward flow of seawater in some of the stretches along the sea coast. During monsoon season, the water table recovers and a positive gradient is setup which generates submarine groundwater discharge into the Arabian Sea.

In Maharashtra, saline water ingress has been reported in isolated areas along the Maharashtra coast.  The studies  carried  out  by  the  CGWB  in  Vasai-Virar  area  of  the  Thane  district  have  indicated  possible seawater ingress in a small area. The main cause of ingress is excessive exploitation of ground water for irrigation, encroachment of sea water into creeks during high tides and salt pan activities in and around the area.

In Goa, the instance of salinity problem is generally not noticed in the coastal aquifer. However, during summer  surrounding  areas  close  to  the  coast,  creeks,  marshy  areas,  islands  and  along  tidal  waves localized salinity has been noticed.

In Karnataka, there is no widespread problem of coastal salinity on the Karnataka coast except at a few sporadic  locations  like  Ullal  Beach,  Mangalore  taluk  of  Dakshina  Kannada  district  and  at  Baindur  in Kundapura taluk of Udupi district. However, it is a localized phenomenon in isolated pockets along the coastal stretch and tidal rivers.

Sea  water ingress has not been  reported by studies  carried  out  by  CGWB  in  Kerala  coastal region.  However, seasonal tidal ingress is noticed all along the coastal region of Kerala.

In  Tamil  Nadu  on  the  basis  of  exploration  and  Groundwater  management  studies  by  government  and non-government  agencies,  certain  areas  (  Minjur  area,  North  of  Chennai  city,  Chennai  District, Tiruvanmiyur-  Kovalam  Tract,  Southern  part  of  Chennai  City,  Cuddalore  Coast,  Ramanathapuram, Nagapattinam, Thanjavur, Tiruvarur & Tuticorin Districts, Kuttam, Radhapuram, Tuticorin District) have been  identified  as  salinity  affected  areas  due  to  anthropogenic  reasons  or  due  to  in-situ  salinity problems. In Minjur area, located north of Chennai city the interface was about 3.5 kms inland in 1972. It has moved to about 15 kms inland at present

In Andhra Pradesh, fresh aquifer zones in the form of unconfined aquifers occur and are limited to the depth of 20 m to 30 m only, followed by confined aquifers which are mainly saline/brackish. However, the salinity of the confined aquifers is attributed to the marine depositional environment in the geological past. As of now, no saline water ingress is observed/reported along the coastal tracts of Andhra Pradesh State.

In  Odisha,  Parts  of  coastal  Odisha  suffers  from  salinity  hazard  which  occurs  to  the  east  of  Kasba Kumurda - Balasore - Gopalpur - Basudevpur - Kothar -Chandikhole - Salepur - Raghunathpur - Niali - Pipli section and extend upto the coastline. No instance of increase in salinity of ground water in the coastal region due to merging of sea water with it has been reported/observed in Odisha.

In  West  Bengal,  the  hydrogeological  continuum  of  the  sub-surface  aquifers,  water  always  flows  and merges  into  sea  water, and  its salinity is  naturally  enhanced,  even  without  any  anthropogenic intervention.

## ANNEXURE REFERRED TO IN REPLY TO PARTS (e) & (f) OF UNSTARRED QUESTION NO. 2540 TO BE ANSWERED IN LOK SABHA ON 17.03.2022 REGARDING 'SALINITY IN COASTAL AREAS'.

## Initiatives by the State Governments to control salinity in the Coastal areas

Karnataka: The  State  government  is  taking  up  schemes  for  construction  of  Vented  dams  and  Salt Water Exclusion Dams in coastal  areas  and  rejuvenation  of  Kharlands  which  is  likely  to  improve  the quality of groundwater in the vicinity in the targeted areas.

Gujarat: The Government of Gujarat (GOG) appointed High Level Committees (HLC) to examine the problems  of  salinity  ingress  along  with  the  coastal  areas  of  Saurashtra  and  Kutch,  and  to  propose remedial  measures,  determine  the  cost  of  the  works  and  set  up  priorities  for  implementation  to  arrest salinity  ingress  and  push  back  the  saline  water  front  towards  the  sea.  As  per  recommendations  of  the committees,  the  State  Government  has  taken  up  some  of  the  works  in  most  affected  areas.  Further, Government has posed dark zone in some area of coastline to reduce over exploitation of groundwater, and also taken up various measures for ground water recharge and also adopted micro- irrigation up to some extent.

Kerala: State Government has installed tidal regulators in major inlets to contain the salinity problem arising out of sea water ingress through the inlets and backwaters.

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