Disposing of dirty paint water – What not to do
Painters wash their tools frequently, especially after jobs with many colour changes. Sometimes there is no access to water, especially when painting in new construction projects. When water is plentiful, some painters wash their tools outside with a hose without considering where the wash water is going. As an environmentally friendly contractor, Ecopainting places great importance to the issue of paint waste.
Pouring paint and paint contaminated water into the storm water drainage system is environmentally irresponsible. Painters need to rethink the common practice of washing their tools outdoors with a hose. The contaminated water enters the storm sewers and pollutes our lakes and rivers. In most municipal jurisdictions this antiquated practice is also illegal. From the City of Markham website:
“The Storm sewers are the grates you see along the streets and are designed to collect rain water and snow melt only – nothing else! This system is in place to prevent flooding in our streets and to re-direct the water to a water source. Water that enters the storm sewer system flows directly into our ponds, streams, rivers and lakes without being treated.”
If you absolutely must wash your tools outdoors, do not use a running hose. Use a small amount of water and clean your tools in a bucket. When you finish cleaning, keep the water and reuse it to wash your tools again or to soak them overnight. When it’s time to dispose the water, use a sink that goes to a water treatment facility.
When water based paint waste enters the waterways
Paints contain solid pigments that can increase the turbidity of water. In addition to making the water “muddy” and unsightly, they can cause particles to clog the gills of fish, and restrict their ability to breathe. Increased turbidity can also block out sunlight and reduce photosynthesis in plants. Paints also contain several biodegradable substances. As they break down, they can reduce the oxygen level in the water making it difficult for fish and other organisms to survive.
When solvent based paint enters the waterways
Solvent based paint waste contains many organic solvents and compounds. These substances don’t mix well with water. When they eventually break down they deprive organisms of the oxygen they need to survive. Solvent paints can contain lead, mercury, zinc and chromium. These heavy metals can contaminate the sediment and poison the food chain. The toxic ingredients in solvent based paints can cause tumors to be formed in fish and other water organisms.
The good news is that the majority of the paints we use today are water based. Whether using water based or solvent based paints, the basic principle remains the same: use as little water or thinner as possible and and reuse it when you can.
In this video, Scott Burt from Topcoat Review, demonstrates a simple wash system for a paint brush.
Practices to Follow when Cleaning Brushes and Rollers
Cleaning Brushes and Rollers from Water Based Paint
Transfer as much paint as possible back to the paint cans by squeezing the brush. Remove more paint by painting a surface with it until almost dry. To clean a roller use a 5 in 1 tool to squeeze as much paint out of it. That technique removes up to 90 percent of the paint. Before washing them, prewash them vigorously in a container with a small amount of water. A five gallon bucket works great for this purpose. Re-use this paint water for the first wash the next few times and eventually let the solids accumulate at the bottom. Dispose as solid waste. A three bucket system of progressively cleaner water works well. If you don’t have the space for this and you are in a hurry, always wash in a sink and not on the lawn.
- Pre-wet your brush and roller with water before using it.
- Use tools that are easier to wash such as the newer chinex bristle brushes and microfibre rollers.
- If you have not finished using a colour, wrap your tools in plastic at the end of the day. This will keep them fresh for the next day.
- Before washing your tools, use them for the first coat of the next colour, when the colours are similar. Before the final coat, just give them a quick rinse as the new colour worked itself into the tools.
Cleaning Brushes and Rollers from Solvent Based Paint
A few years after the original blog was written I am happy to say that we don’t use any solvent based paint. Occasionally we need a solvent based primer or a specialty metal coating. Most of the time we use inexpensive brushes and rollers, we let them dry and dispose them as solid waste.
If you are using your tools for same or very similar colours wrap them in plastic and keep them in the freezer. They will stay fresh until you need them again.
During the Toronto winter leave them wrapped outside or in your trunk. Left outside paint brushes and rollers wrapped in plastic can keep fresh for days. Read more environmental tips.
Note: when you need to dispose dried up tools and solvent waste, contact your municipality for their waste disposal policies
What To Do with Leftover Paint?
Paint contractors constantly deal with the issue of leftover paint. We order for a project and despite our efforts at accuracy, we end up with extra paint. If it’s a small amount we leave it with the customer for future touch ups. If we have leftover gallons of paint we organize giveaway events at our shop and share our leftovers with the community.
If you are a DIYer and you have leftover paint, drop it off at a retailer such as RONA and Home Depot.
If you have unopened paint cans you don’t need, contact Ecopainting at 416 733-7767. We will add it to our inventory for our next paint giveaway event.
We discussed the washing of paint brushes and rollers because these are the main tools our painters use. Painters washing their spraying equipment can follow the same basic rules about paint water waste.
This blog was first published on June 12 2013 and updated on April 1st 2017.