Commercial fishfarms if they should be developed in the future, must not be sited where the soil is sandy and where seepage would be to a considerable extent thereby creating problems and the impossibility of water replenishment.
Fishfarm sites so selected shall be such that the ponds built can be drained dry by gravity flow. This is to enable the farmer to prepare/recondition the pond soil, level the pond bottom and to eliminate all predators.
Pond design shall be such that water exchange in the required amount in percent of the pond water (10%) volume done at specified times during the culture period can be attained.
Preference shall be given to designs of a fishfarm, in the order of priority, to be fully tide-fed, partially tide-fed and partially pumped fed, and lastly pump fed.
There is a need to modify the layout of farms now under construction. In view of this, construction work be stopped until revisions on plans and designs have been done and that work can continue only when a qualified engineer will have been assigned to supervise the work of the contractor in accordance with materials and work specifications that shall be drafted and made a part of the contract documents.
Preference to pond shape shall be on the rectangle with long to short dimensions in the ratio of 2 to 4:1, and the ponds shall have inlet and outlet gates at the opposite short sides; the ponds would have filling and drainage systems permitting them to fill and drain independently of the other ponds.
The following fishfarms have been selected, by remodelling, to become pilot models and, now pilot model designs are recommended to be drawn for development in the brackishwater sites mentioned:
Type I | - | Matwad fishfarms in the Gujarat State; Construction work has stopped and resumption shall be done when improved designs will have been drawn. |
Type II | - | Alampur fishfarm in the West Bengal State; Total remodelling will have to be done. |
Type III | - | The brackishwater estuarine areas north of Ratnagiri town by the Shirgaon creek have potentials for fishfarm development. A pilot model shall be drawn and be developed in the area. |
Type IV | - | The Polekkuru fishfarm under construction; Further resumption of work shall be done only when there shall have been drawn new and improved design. |
Type V | - | The project team has not been able to locate a brackishwater estuarine area that is suitable for development of a pilot model. The several fishfarms visited do not possess the requirements for suitability for a pilot model even by remodelling. |
Equipment for preliminary survey shall be made available and these are: soil auger with extension, apparatus for field measurements of permeability of soil, pedometers, magnetic compass, hand level, soil sampling equipment and various meters.