What you see
Slow, steady drop during hot windy weather
More likely cause: evaporation.
Check next: compare the loss with nearby dams and recent weather.
Dam evaporation & water loss diagnosis
Dam Evaporation Control and Water Loss Management
If your dam is dropping, the first job is working out whether the water is evaporating, leaking, seeping through the wall, or escaping through a pipe or spillway problem.
Short answer: Dam evaporation control starts with diagnosis. In hot, dry or windy weather, evaporation can remove a surprising amount of water, but wet patches below the wall, fast water drops, sinkholes or green strips often mean leakage. Big Ditch checks the cause before recommending shade balls, floating covers, wind protection, dam sealing, repair or rebuild work.
Is your dam leaking or evaporating?
What you see
Wet patch or green strip below the wall
More likely cause: leak or seepage.
Check next: inspect the toe, wall and downstream area.
What you see
Fast drop after filling
More likely cause: leak path, poor clay or pipe issue.
Check next: check old pipework, rock seams and wall compaction.
What you see
Water loss plus sinkholes or soft spots
More likely cause: internal erosion or piping.
Check next: stop guessing and get the dam inspected.
Evaporation control options
Shade balls or evaporation balls
Useful where surface exposure is the main issue and the dam shape suits a floating cover approach.
Floating covers
Can reduce direct sun and wind contact, but need the right installation and maintenance plan.
Wind protection
Windbreaks and edge planting can reduce surface disturbance on suitable sites.
Dam shape and depth
Shallow dams lose more water. A deeper, better-shaped storage can reduce evaporation pressure.
Leak repair
If the problem is seepage, evaporation products will not fix the real cause.
Water-use planning
Sometimes the right answer is storage design, pumping schedule or extra capacity.
Do not buy evaporation gear until the cause is clear
If the dam is leaking through the wall or pipework, a cover or shade-ball system can waste money. Diagnose the water loss first.
When evaporation control is not enough
Evaporation management helps when the main problem is weather exposure. It is not a substitute for dam sealing, wall compaction, pipe repair or rebuilding a failed section of dam.
Field note: A dam can be evaporating and leaking at the same time. The practical question is which loss is costing you the most water and which fix will actually work.
Related Big Ditch services
Frequently asked questions
How do I know if my dam is losing water to evaporation?
Compare the water loss with weather conditions and nearby dams. If the drop is much faster, or there are wet areas below the wall, investigate leakage.
Do shade balls stop all evaporation?
No. They can reduce surface exposure in suitable applications, but they do not remove all evaporation and they do not repair leaks.
Can Big Ditch check whether my dam is leaking?
Yes. Big Ditch can inspect the dam, wall, toe, pipework and site conditions to work out whether water loss is evaporation, seepage or structural leakage.
Get the cause of water loss checked
Tell us how quickly the dam is dropping, what the weather has been doing, and whether you can see wet areas below the wall.