Water Conservation

There are many ways for you to conserve water in your landscape.

See our tips and resources to help you save money on your water bill, or learn how graywater can help you conserve water indoors and in your yard at the same time!

Why Conserve Water?

It rains so much here – why do we need to conserve water?

There are many good reasons to conserve water. Here are just a few:

Reducing your water use can help you significantly lower your water and sewer bills. This includes both water use in the home and in your yard.
We conserve water by creating drought-resilient landscapes, which also offer many other environmental benefits. When we infiltrate stormwater runoff (rain water that runs off the surface of an area, instead of being soaked into the ground) into the ground instead of sending it to the storm sewers, it cleans the water, recharges our local streams and aquifers, reduces the load on our sewer systems, and helps prevent flooding. Learn more in the Rain Gardens section of our website.
Finally, we have one of the best water systems in the world. A century ago, some thoughtful individuals had the foresight to set aside and protect an entire watershed (an area of land where all of the water that is under it or drains off of it goes into the same place) so that our water source would remain pure over time. The more we conserve water, the less demand we put on this system, and the less need we will have to seek other water sources.

Where Does Our Water Come From?

An illustration of our water system, courtesy of the Portland Water Bureau. On the far right is Bull Run Lake, and at the top middle is the Columbia South Shore Well Field.

Our primary source is the Bull Run Watershed, a 102-square-mile area that collects water from rain and snowmelt.

It then flows to the Bull Run River, where it is stored in reservoirs that hold 17 billion gallons and provide water to more than 900,000 people!

Water from the Bull Run Watershed is delivered by gravity (no pumps needed) and is not filtered! It requires minimal treatment, including chlorinamination – the process by which chlorine and a small amount of ammonia are added to a water source to create a long-lasting disinfectant, which is especially useful in larger water distribution systems – to disinfect the water, and a small amount of sodium hydroxide to reduce acidity, which helps prevent corrosion in plumbing systems.

We also have a secondary source of water, the Columbia South Shore Well Field, that draws groundwater from several adjacent aquifers. It is used both during emergencies and to augment the Bull Run supply in the summer.

Outdoor Water Use

The Portland Water Bureau states that 60% of our household water use is applied to our landscapes.

If you consider that the average household uses almost 45,000 gallons per year, that is almost 27,000 gallons being used for landscape irrigation – for just one household!

When we are using more water than can be safely drawn from the Bull Run Watershed, we revert to using groundwater from the Columbia South Shore Well Field.

This water requires pumping, as well as additional piping and infrastructure. This water source is typically used every summer, when outdoor irrigation and watering are at peak levels.

How Can We Reduce Our Water Use?

One easy step we can take is to make our landscapes less thirsty!

And one of the best ways we can do that is to remove our lawn and replace it with native plants that don’t need summer watering. Disconnecting your downspouts and soaking the water into a rain garden, instead of sending it to the stormwater system, also helps replenish the local water table and can make your landscape more drought-resilient. For any part of your landscape that still needs irrigation, you can avoid overwatering by following the Weekly Watering Number.

We offer free workshops and short presentations on ways you can conserve water and energy by landscaping with native plants, planting a rain garden and more!

You can also check out our Water Conservation Tips and Resources page!

Finally, your local jurisdiction may offer rebates, incentives and/or free devices to help you conserve water at home. Check out the resources available to you if you live in the following cities: