Management of fish ponds to control erosion

Erosion is wearing a way of soil, rock or dissolved materials from one location and transport it away to another location by erosion agents like water and wind.

In fish pond, erosion occurs as a result of wave action, water currents from aerators and rainfall that degrade the walls and bottoms of a fish ponds lead to creation of deep cuts and holes at side walls and bottoms of ponds.

Erosion along side walls of a fish pond

Fish farmer should understand that erosion of pond is a serious matter because soil particles worn out by erosion increase total suspended solid concentrations in pond water and effluents, clay particles increase turbidity in turn lead contamination of surface water with suspended solids.

It is true that some of practices that fish farmers tend to ignore during management have effect on pond erosion  although most of us consider fish feeds, predators and fish alone as important while forget some issue like :

Control of water level in a fish pond

It should be noted that, erosion tend to be severe when water levels on wet side of pond that provided protection from wave erosion.

Completely or partially empty of ponds: give a chance to rain falling on exposed bottoms may cause severe erosion

Complete empty pond 

Aerators generate strong water currents that can suspend soil particles from pond bottoms and detach soil particles.

Strong water currents generated by aerator

Open the drains of empty ponds allow turbid water from entering streams

Allow natural trees to grow around or near the fish ponds :Some trees  tend to spread far and have a strong roots hence in turn degrade the side walls of ponds make them weak that can be easily eroded by wind, aerators currents and rainfall.

*Not all trees are bad but some forexample Neem tree has property of having deep and big roots that can erode rocks or any hard substances.

Neem tree

Some aerators forexample stationary tractor mounted, electric paddle wheel aerators and tractor powered aerators tend cause erosion in higher extent.

Advises to the fish farmers

Prevent and repair immediately damage caused by vehicles or any other equipments.

Avoid sediment accumulation on unvegetated piles, rainfall on spoil piles will cause erosion and the run off will be turbid with suspended soil particles.

All aerators must be installed near ponds but should be at least 3 ft. deep directly below the paddle wheel.

Close the drains of empty ponds to prevent turbid water from entering streams.

Areas in front of aerators should be covered with stones.

Plantation of grasses around the sides of ponds includes walls and dykes surfaces to control water run off that lead to erosion.

If a farmer want to plant trees in his or her fish farm, he or she should make sure trees are planted far away from the fish ponds to prevent erosion to occur.

Below inlet pipes, hard rock or gravels should be placed to prevent water from inlet pipe to erode bottom sides of the fish ponds.

Instead of using electric paddle wheel, a farmer may opt to use simple paddle wheels that are made by wood that has low erosion.