
| Inland Aquaculture Engineering (1984) |
| DESIGN AND CONSTRUCTION OF FRESHWATER FISH FARMS |
![]() | Chapter 6. Principles of Designing Inland Fish Farms |
![]() | 2. PREPARATORY WORK |
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Topographic surveys to the scale 1:500 to 1:5000 and with contour lines of 20-25 cm (perhaps 1 ft) vertical spacing are needed for the entire fish farm area, in order to permit designing complete pond drainage and earthwork volume estimates of the required accuracy.
On any existing earth structures (embankments, canals, etc.) cross sections should be taken at 50-100 m spacing, with points spaced sufficiently close to each other to plot the actual terrain with ± 20 cm accuracy on the cross sections of 1:100 scale.
Cross sections should be plotted at the sites of major structures (intakes, road crossings, etc.)
Cross sections at not more than 500 m intervals and continuous profiles are needed on the connecting stream or canal extending for the distance affected by the fish farm (e.g. to the backwater limit).
The topographic survey should be connected, especially as regards elevations, to the national survey network.