Using Low Impact Development (LID) Methods

By Scott Chase, Class of 2002, SWS Stewardship Committee, SWS Education Committee, SWS Board Member

anacortes-downspouts
Restaurant downspouts along Anacortes waterfront empty into rain gardens next to the building. Rain falling on paving is diverted into planting strips on both sides of walkway.

Low Impact Development (LID) refers to a suite of practices to keep pollutants from entering our waterways and the Salish Sea as a result of rainstorms and snow melt. LID encourages people to conserve water and use existing property features to copy water patterns found in nature. LID involves allowing plants, soil, and microbes to naturally hold and filter storm water while also recharging groundwater. Common LID projects include permeable paving, vegetated roofs, rain barrels, and rainwater catchment, along with soil amendments for better absorption. We’ll explore a few LID examples that contribute to healthy shoreline living. By keeping LID principles in mind as you plan your home and garden projects, you can truly enhance your property and protect the Salish Sea for years to come. Stormwater management not only prevents damage to property from flooding, but also the quality of our water. LID can be used with new development as well as with existing homes, both urban and rural. Although some techniques require some engineering, others are quite simple.  With all, you need an understanding of how water flows to and from your home and land.

Low Impact Development practices are not advised or recommended in certain situations. Although infiltration of rainwater into the soils is usually desirable, directing water to some locations may flood crawlspaces, create problems with septic system drain fields, or de-stabilize slopes and bluffs. Check this link to the WSU Shore Stewards “Guide for Shoreline Living” publication. Guideline 4 covers “Managing Water Runoff.”  In the left column, you’ll also find a link to Guideline 5 “Reducing Erosion and Landslide.”  Each Guideline includes multiple links to helpful sources.  Guideline 4 – Managing Water Runoff | Shore Stewards | Washington State University (wsu.edu)   Be sure to seek professional advice regarding drainage methods if needed.  

RR Ave,, Anacortes mitigation
Part of the Railroad Avenue Mitigation Project in Anacortes includes whimsical downspout “watering cans” around the perimeter of the Rope Building, which flow into rain gardens next to the building. Rainwater falling on pavers in the foreground seeps through the cracks between the pavers and into the ground.

Some LID techniques you might consider for your own property include:

  • Preservation. Keep as much of the desirable, existing soils and vegetation as possible.
  • Amending soils. Adding compost to soils that may have been disturbed during construction helps to restore the soil’s health and ability to infiltrate rainwater. You can also do this project on your existing property.
  • Pervious paving. Alternative forms of paving allow rainwater to soak through the paving rather than flowing across it. Pervious pavers and grids are a good example, and are available at home centers and some nurseries. These simple paving options that you can install yourself reduce runoff, provide filtration, and enable water to soak into your soil to replenish groundwater.
  • Rain gardens. Essentially a shallow depression constructed to fit your yard, using a special soil mix along with a a variety of plants that are specifically selected for rain gardens. This special soil mix supports plant growth, holds moisture and allows the water to soak in. Rain gardens are not suitable in every location, especially near a bluff. More information can be found at  Rain Gardens | Washington State University (wsu.edu) 
  • Rain Barrels. Simple to install, rain barrels are a rain catchment alternative that allow you to collect the water from your roof to reduce and channel stormwater flow, as well as provide supplemental water for irrigating your garden during summer months. For information on how to create and install one or more rain barrels on your property, go to SHORE STEWARDS NEWS (wsu.edu)
downspout-with-a-message
Downspout with a message

This article is the Stewardship Column in the monthly e-newsletter. Photos and text by Scott Chase.

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