Presentation on theme: "Irrigation Department"— Presentation transcript:
1 Irrigation Department WELCOMEIrrigation DepartmentKilinochchi
2 WATER RESOURCES DEVELOPMENT OF JAFFNA PENNISULA BY DEVELOPING JAFFNA LAGOON SCHEME By Provincial Irrigation Department
3 CONTENTS · Objectives · Involvement of Provincial ID · Components of Jaffna Lagoon Scheme · Problems · Identified Proposals · Irrigation department Findings
4 OBJECTIVES · To introduce the components of Jaffna lagoon scheme · To summarise the identified proposals so far · To explain the present situation of the Jaffna lagoon scheme · To recommend some proposals for immediate implementation · To recommend some proposals for future studies · To recommend some proposals for future implementation
5 Involvement of Provincial Irrigation Department In Jaffna Peninsula Northern Provincial Council Ministry of Irrigation, Agriculture, Lands, Fisheries, and Animal production Prov.Director of Irrigation Prov.DDI, Kilinochchi Range Irrigation Engineer, Jaffna.
6 IE, Jaffna is responsible, on be half of the Government of Sri Lanka for operation and Maintenance of; · Valukkaiaru Drainage Scheme· Upparu Drainage Scheme· Thondamanaru Drainage Scheme
7 Valukkaiaru Drainage Scheme Now Barrage is being repaired
12 Problems · Un controlled pumping and no planning for recharge of ground water is causing severe threat to the ground water potential as well as quality of water in Jaffna peninsula · Due to the non maintenance of the salt water exclusion system in Jaffna peninsula, sea water intrusion has taken place in to the land area · Many thousands of acres of fertile land has become saline and abandoned with out cultivation in Jaffna peninsula · Many hundreds of dug wells have also been abandoned due to salinity
13 History and Proposal of JL Scheme Mr. Twyneham GA, NP, has proposed Damming the sea water from entering to the lagoons – - Given up due to big flood disaster Mr. Fesling GA, NP, Took it up the proposal and given upMr.Horesburg started the part of the project, Blocked the Culverts across Point pedro – Chavakachcheri road – It was functioning well from 1920 to 1923Mr.Webb proposal came up – Thonadamanaru Barrage Constructed1947 – 1953, Ariyalai Barrage constructed -1955 Eng.S.Arumugam has proposed converting Elephentpass lagoon and Vadamarachchi lagoon in to Fresh water lakes to accelerate the leaching process. It got failed – becauseØ Sea water seepage through Kandy Jaffna road bridgeØ Damage of Eastern closure bund due to the settlement of subsoil below the bund
16 Proposal from Irrigation Department in 1976 headed by Eng. K Proposal from Irrigation Department in 1976 headed by Eng.K. ShunmugarajahEastern closure bund of 4700ft with the spill cum causeway of 7000 ft. Access road of 6 miles also planned to be improved Link canal of 2.5 miles with regulator Imp.to Thondamanaru Gates Repairs to Ariyalali Barrage Gates Separation Bund at Kaputhu Imp. to all Flood bundsBenefits shall be anticipatedReclaiming 11,000.00acs of non arable landSupplement 20,000.00acs of rain fed cultivated land for goodand assured yield Ground water improvements in the peninsulaLivestock improvements in the lagoon surrounding areaIn 1983, the summery of Mr.K.Shunmugarajah’s report was submitted toHis ExcellencyMr.J.R.Jayawardana, President of Sri Lanka, on his request.By ; Prof. H.W.ThambaiahEng.S.ArumugamEng.K.Shunmugarajah
17 Existing Features Thondamanaru Barrage Total length 628ft Ariyalai barrage540ft lengthNo of upper gates 18Size 20ft*4ftSill 0No of Gates 42Size 5.5ft* 5.0ftSill -1.0MSL - Crest +4.0MSLNo of lower gates 13Size 20ft * 3ftSill -3No of subsidiary sp gates 16Size 20ft * 2ftSill +2Tot.Area of Jaffna400 sq.mlVad lagoon area30 sq.mlUpparu lag.area10 sq.mlEP lagoon area40sq.mlCatchment area of Vad.Lagoon Tot.Area of Jaffna115sq mlCatchment area of Upparu85sq.mlsCatchment area of EP363sq.ml
18 Irrigation Department Recommendations Upparu Scheme1. Ariyali Barrage gates could be rehabilitated with necessary improvements.2. All Flood Bunds or Salt Water Exclusion bunds could also be rehabilitated including the drainage channel clearing, and de-silting the lagoon area to the original profile. 3. Upparu lagoon could be considered to divide the area into THREE or FOUR sectors by constructing Barrage or gates to the bridge as shown in the map4. Separation Bund is not necessary, since both the lagoon are going to be with fresh water. But for the safe side, it is better to consider the rehabilitation. 5. If it is necessary, the first sector, could be considered for CONTROLLED SALT WATER CONTENT AREA for the development of Salt water fishing and its related activities. ( Further studies are Required)
20 Vadamarachchi lagoon Thondamanaru Barrage repairs is being done 2. Vada. Lagoon could be divided into FIVE SECTORS by constructing, Barrage or gates to the bridge at Vallai Chavakachheri road, Mullipalam, Pallai road and finally the gate at mandalai as shown in the 3. The first sector from Thondamanaru to Vallai shall be considered for CONTROLLED SALT WATER AREA for the dev. of fisheries sector. ( Further Studies are required) 4. All Flood bunds or Salt water exclusion bund along the periphery of the lagoon on either side shall be rehabilitated including de-silting the lagoon to the original profile. 5. Further studies are required
22 Eastern and western sides of the lagoon could be kept with salt water. Elephent Pass lagoonEP Lagoon could be divided into THREE SECTORS by constructing peripheral bunds leads to send flood water as well as drainage water to Vad.lagoon through Mandalai- Mthurankeny cannel as shown in the mapEastern and western sides of the lagoon could be kept with salt water.
24 Further studies and final investigations are required to; Section of the peripheral bund ( it is advisable to have clay core and rock fill bund to function as spill cum bund)Width and discharge of the two peripheral channels and channel leads to Vad. Lagoon have to be decided ( 5000 cusecs and 250 to 300 ft BW)Is the opening of EP Bridge to be reopened to discharge the flood water – western portion to the seaIs it possible to issue water from the Iranaimadu tank to supplement drainage water, when it is not enough to cater the nominal demand of water to Vad.Lagoon