ENVIRONMENTAL CONCERNS IN THE ACCELERATED MAHAWELI PROJECT

Abstract

The Mahawcli Development Project is the largest single development programmeundertaken by the Govcmmcnt of Sri Lanka. The Accelerated Programme which wascompleted in :') years envisaged the construction of 4 major reservoirs with hydro-electricityplants. developed about I7:')J60 ha of lands in the downstream areas with irrigationfacilities and established new sculcmcnts of about 74253 families. New and improvedcultivation resulted in the annual production of more than 600.000 tons of rice. Thereservoirs increased the hydroelectric gcnerating capacity hy about 400 megawatts.

Among the impacts of the Upper Mahawcli Catchment which includes watersheds andxubwatcrshcds of Kotmalc Oyn. Maha Oya, Urna Oya, Beli-hul Oya is vital as the principlesource of water for hydropower and irrigation projects. Among the threats to theenvironment. the premature silting up of a number of reservoirs especially Polgolla.Raruambe etc. can be noted. Deforestation for chcna cultivation in the steep slopes coupledwith the high water table prevalent in the area results in carthslips and landslides.Deforestation has also caused significant reduction in wildlife habitats in both upstreamand downstream areas. A large number of animals and plants including endangered,threatened and endemic species had been reduced. Due to the use of high quantities ofagrochemicals the agricultural return waters has caused eutrophication in reservoirs. tanksand other w.ucrhodics impairing the effective functioning of these entities and affecting thelife Iorms in them.

Among the significant concerns in the downstream areas. rise in the watcrtable thusnecessitating drainage. increased salinity in some areas, contamination of natural waterways due to high usage of agrochcmicals in agricultural practices. increased encounterswith pocketed wild animals causing death and damages to property can be cited.

Among the social concerns or the settlements, necessity of high inputs thus reducing thcnet income of the Iarrners. inability to manage holdings with family labour. inadequatesupplies of irrigation water. inadequate service facilities (transportation, schooling. hcalthctc.), rcstrictcd/un employment or the second generation settlers. increased incidence orwater horne and vector horne diseases. teenage suicides can be mentioned.

Mitigatory measures which have already been taken by Mahaweli Authority to addressthese conccrnx have been stated along with some recommendations fort the future toachieve the objectives 01" the Mahawcli Programme on a environmentally sustainablemanner.