Preventing mosquito breeding in stormwater tanks is an important part of maintaining a safe and effective harvesting system. Mosquitoes are drawn to still, standing water where they can lay eggs, so it’s essential to design the system in a way that limits stagnant conditions. One common method is to ensure that tanks are sealed or covered with tight-fitting lids or screens that prevent insects from entering. Inlets and overflows should also be fitted with fine mesh to block access points.
Keeping the water moving is another key strategy—circulating the water with pumps or using floating devices that create surface movement can disrupt mosquito breeding. Regular maintenance plays a role as well, since cleaning out debris and checking for clogs helps prevent water from pooling in unintended areas. If needed, biological controls like mosquito dunks containing Bacillus thuringiensis israelensis (Bti), a naturally occurring bacteria that targets mosquito larvae, can be used safely in non-potable systems.
