Babar Effendi is the former Secretary Irrigation Sindh with a vast experience in irrigation engineering. He has also served as Managing Director Sindh Irrigation and Drainage Authority (SIDA). We talked to him about a hypothesis ‘Can Sindh’s agriculture survive even if Tarbella Dam is completely silted up and also we are unable to build a new dam.
We must have our own water reservoirs whose ownership should exclusively be with us (Sindh) and we should be the operators of such reservoirs. Sindh can face droughts like the concurrent one only this way. If we take efforts and use best of engineering we can develop our depressions as reservoirs.
We have many sites in Sindh which can be turned into water reservoirs. For instance, at present we have Chotyari Reservoir (Sanghar district) having a water storage capacity of 0.7 MAF. It is originally designed at 0.8 MAF storage capacity. Then Keenjhar Lake (Thatta district) is available which can stores 0.5 MAF of water at present. Manchar Lake (Dadu district) is a 0.35 MAF pond. Also, we have lakes like Hamal, Udero, Haleji, Akro besides others in various districts. They should be explored.
Sindh has nine wetlands which are recognized as Ramsar Sites. They all should be revived. Likewise, in Thar area, there are many such depressions also. If we plan and manage them as reservoirs which should be filled with flood waters, they can provide water for irrigation in Rabi season.
Chotyari Reservoir can provide water supplies to lower Nara (Thar division which includes Umerkot and surroundings) and Mithrao where a double action regulator called Aaju Regulator is used as an escape and a feeding source. Some supplies can also be directed to Jamrao also.
Manchar Lake can be raised more as a reservoir. It will create resettlement issues which are to be managed properly. With present capacity, Manchar Lake which was named as a Reservoir by Z.A Bhutto is providing water to over 2.5 lakh acres of agricultural lands.
In this plan, escapes routes for Indus River to mitigate the effects of floods are also required. When I was Secretary Irrigation Sindh we surveyed about the escapes of Indus. One is Thori where Indus River had a breach and thus the flood water reached Manchar Lake. It is a natural escape which can be used for filling Manchar during floods. Same route would supplement Hamal Lake also through Hairdeen Drain. Hamal Lake’s spillover irrigates lands in Kacho area of Sindh.
Another escape is present upstream of Reni Canal which was proposed by the irrigation department. Over 50 thousand cusecs of Indus water can be diverted through such escape. Reni and Nara can lead us to Thar.
Sindh has already implanted small dams along Kirthar Range and many small drains have been built there. Most of them are recharge dams. Then there is yet another dam namely DarawatGaj Dam on NaiGaj is also under construction.
Sehwan Barrage is yet another project which could be used for this purpose. If half of Rohri Canal is supplemented from proposed dam, the tails of lower Sindh would get plenty of water for irrigation and drinking purposes.
Sehwan Barrage has already been studied properly and at the same point reservoir like Chashma Barrage can also be built.
Sindh should also contemplate Delta Barrage which should be double action releasing river water into sea during foods and stopping high sea tides during low flows in the river.
Of the sources Sindh has, Left Bank Outfall Drain is also available. The LBOD runs on fresh water 5 months a year. This water comes from escapes of Mithrao and Jamrao escapes which work during floods. This water ultimately goes to Dhoro Puran which enters Shakoor Lakre of which bif part is in india where this water is being used for cultivation.
We have had a study on how to divert Dhoro Puran water and to use it in Thar for agriculture. (By Manzoor Shaikh)