A number of solutions to the problem are available.
The most effective solution is to install a dam liner which is a guarantee to fix the problem. However this method is expensive and the liner can only be installed when the dam is empty.
Other problems with lining a dam is that it must be fenced to prevent stock walking on the liner and damaging it, which means a trough and pump have to be installed to do the job of stock watering that the dam is supposed to do.
Therefore it means waiting till the dam is empty or having to pump out the stored water and hope for heavy rain. Another solution is by adding chemicals which combine with the soil to stop the leaks. Again this can be expensive and is not guaranteed to work if there is insufficient clay or tree roots in the dam wall.
Installing a solar pump is a guaranteed solution and once installed costs nothing to run. A simple solution is to make a small pond below the dam wall and install a solar pump to to pipe the water back into the dam. As solar pumps only operate in daylight hours the pond needs to be about three times the daily leaking volume. For example a dam leaking at 2.5L/M or 3600 liters per day had a 12000 liter pond constructed and a solar diaphragm pump with a capacity of 17 L/M installed and the problem was solved. Even on overcast days the pond did not overflow and a float switch was installed to turn off the pump at the low water level.
There are two types of solar pumps suitable for this application.
One is a submersible connected to the solar panels via an inverter which converts the DC current from the panels to three phase AC power to the pump. To prevent the solar water pump from running dry, high water and low water probes are installed which are connected to the inverter.
The other suitable solar pump is a less expensive fixed displacement diaphragm unit which is connected to the solar panel via a battery. To prevent dry running an inexpensive float switch can be installed.
To increase daily flow rates by 30% a solar tracker can be installed.
Most dam leaking problems can be solved with solar water pumps but if the leak gets to unacceptable flows other solutions may be needed but the solar pump can still be used for other applications.