The Department of Health recommend that the following components of the roof catchment and tank must be inspected by you at least every six months:

Internal inspection – check for evidence of access by animals, birds or insects, including the presence of mosquito larvae. If present, identify and close access points. If there is any evidence of algal growth (green growth or scum on or in the water), find and close points of light entry.

In addition to six-monthly inspections, the tank should be inspected every 2-3 years for the presence of accumulated sediments.

If the bottom of the tank is covered with sediment, it should be cleaned.

Gutters: they generally will need inspection and cleaning. If the inspection finds large amounts of leaf material or other debris, the inspection and cleaning frequency may need to be increased.

Roof: check for accumulated debris, including leaf and other plant material. All accumulated material should be removed. And prune any overhanging branches.

Tank inlets, insect-proofing and leaf filters: if necessary, these should be cleaned and repaired.

Tank and tank roof: check the tank’s structural integrity, including the roof and access cover. Any holes or gaps should be repaired.

Pipework: check for structural integrity. Empty any sections of the pipework that are not self-draining. Buried pipework, such as with ‘wet systems’, can be challenging to drain or flush. If possible, install some drainage points.

Rainwater tanks can become a significant mosquito breeding site when they are no longer required or fall into disrepair. Tanks that are no longer needed should be drained, cut up and removed to an appropriate waste disposal site.