Balancing ponds
What are balancing ponds?
Balancing ponds, also known as flood or attenuation basins, are a form of drainage commonly found around new construction projects.
Balancing ponds collect and hold surface water and slowly release it into the drainage system or surrounding ground.
During heavy or prolonged rainfall, they collect excess water to prevent the drainage system from becoming overwhelmed and reduce the likelihood of flooding.

What do I need know about the pond near my home?
Generally, balancing ponds are considered low risk. However, it’s important to say that they’re not areas for play. The ponds typically have steep sides, and the water levels can change quickly after prolonged wet weather.
 If anyone accidentally falls in and can’t get out, you should immediately call 999.
Are balancing ponds dangerous?
Balancing ponds require regular maintenance and are subject to several inspections every year.
If you notice the pond near your home is overgrown, contains rubbish or if the water level doesn’t appear to fall following prolonged wet weather, please call us on 0800 111 4013.
Dos and don’ts
Download a PDF factsheet
Download this factsheet as a PDF file
Updated: 30 May 2025