How do I safely dispose of paint and chemicals?

This is a question that crops up again and again – and not knowing the correct way to throw away unwanted paint or chemicals often leads people to guiltily toss them in with the general rubbish, or worse, down the drain – believing that the sewage plant will be able to remove them, perhaps not even knowing that the drain’s not a good hazardous waste destination.

The truth is that after treatment in a sewage plant, water is discharged into rivers, lakes and streams. Most municipal systems rely on bacteria or other organisms to decompose the waste. Some hazardous household waste can pass through the system unchanged and thus pollute the water downstream, and some chemicals can also corrode the plumbing or collect in the trap and release potentially toxic fumes through the drains.

It is illegal to pour chemicals or detergents into a storm drain.  The storm sewer system which is where most open street drains lead, usually sends rainwater directly to the receiving lake or river completely untreated.

In much of London, the drainage and sewerage systems are combined. This means that a lot of the dirty water that goes down storm drains is actually taken to the sewage works for cleaning before being returned to the Thames. But when rain is heavy, the system becomes overfull, and raw sewage overflows through storm drains into the river. This sewage is mixed with other pollutants such as oil from the roads and can be a deadly mixture.  Pouring chemicals and paint down either the storm drain or into a household drain means that a highly toxic concoction reaches the Thames River, poisoning aquatic life and harming our environment.

The Water Industry Act 1991

The Water Industry Act 1991 regulates discharges to the foul sewerage system and makes it an offence to discharge trade effluent to a public foul sewer or a private foul sewer that connects to a public sewer, without prior consent.

Trade effluent is defined as liquid waste discharged from premises being used for a business, trade or industry, except domestic sewage and clean uncontaminated water.


Disposing of Water-Based Paint

Liquid paint should not be put into a residual bin, in a skip, or poured down a sink. Use the following method when disposing of water-based paints:

 For paint residue in a tin:


  1. Remove the lid and allow to dry completely.
  2. Remove the skin and dispose of it in residual bin.
  3. Recycle the tin.

 For excess paint:


  1. Fill a paper bag or box with sand or saw dust.
  2. Pour the remaining paint over the absorbent material.
  3. Allow to dry completely in a well-ventilated area away from direct heat.
  4. Dispose of the solid waste in your residual bin.

 Washing your equipment

If paint utensils and materials are being washed in a sink connected to the main sewerage, the residue water may be classed as trade effluent and need a trade effluent licence. Check with the local water company if authorisation is required.

Disposing of Chemicals, Oil-based Paint and Solvents

Oil-based paint and solvents, including spirits, are considered hazardous waste materials and should be disposed of accordingly.

 Never dispose of liquid oil-based paint or solvents in your residual bin and never pour them down the sink.

 For businesses:

Find a licenced hazardous waste mover on the Environment Agency register

For householders:

The City of London authority operates a household hazardous waste collection and disposal service for residents on behalf of most of the London Boroughs.

  • It only collects boxed chemicals and paint.
  • You are entitled to three collections of 50L of containers per rolling year.
  • Chemicals and paint tins must be put into cardboard boxes for collection.

Apply via this online form

or phone 020 7332 3433.





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