Midges on our sites

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We’re aware that customers who live close to some of our sites may see swarming midges (known as chironomids) in or around their properties.

Are these midges a health hazard?

  • Although the swarming of these insects, sometimes in considerable density, can be a nuisance, they are NOT harmful or hazardous to health.
  • These midges have no mouth parts and are unable to bite or sting.
  • They do not spread disease.

Why can’t Thames Water get rid of them?

  • It is illegal to apply insecticide where there is a risk it could drift into other properties.
  • Even if we were allowed to use insecticides, it would be impossible to completely eradicate the midges as they occur naturally near areas of open water.
  • Midges are an essential part of the food chain, being vital food for birds and other wildlife on and around our sites, so eliminating them entirely could have a serious impact on wildlife.

What are midges?

  • Midges are flying insects that vary in size depending on the type of species.
  • There are many different species that emerge at different times of the year mainly between March and October.
  • The adult stage lasts for only about one week during which time they swarm as part of the mating process.
  • Feel free to contact us regarding midges, this will help us identify the areas worst affected.

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