Gaining ground for the Puget Sound
May 3, 2012
By Christina Lords
12,000 Rain Gardens campaign aims to curb pollution, create beautiful landscapes
As more than 14 million pounds of toxins enter the Puget Sound each year, two Washington entities are working hard to curb the contamination — 12,000 times over.
The 12,000 Rain Gardens in Puget Sound project, spearheaded by Stewardship Partners and Washington State University, aims to grow and designate 12,000 rain gardens — which reduce pollution and alleviate flooding all while creating attractive landscapes that promote native plant growth in hearty soil — in the area by 2016.
The gardens, which can be shaped and sized to fit most yards, act as a collector for runoff during a rainstorm. With a crucial element — the right kind of soil — the gardens work to absorb and filter storm water runoff from impermeable surfaces, such as rooftops and driveways.
More than 700 rain gardens have already been planted throughout the region.
“It’s not just a feel-good, tree-hugging thing,” said Kenan Block, vice president of the stewardship partners board. “It’s a practical thing. Neighbors get to know each other while doing these things. The community building experience has been an unintended benefit of this project.”
Block said one of the main benefits of creating a rain garden on a home or commercial property is its ability to filter a variety of pollutants, such as oils, greases, fertilizers and pesticides, before they reach the storm drain while simultaneously reducing flooding on neighboring properties and curbing overflow in sewer systems.
“Most of us, when we think of serious pollution, are shocked to find out how much of this area’s worst pollution comes right from our sidewalks, streets and roofs,” he said. “That includes the things we put in gardens as well, such as pesticides and herbicides … Some contaminants, while they may seem like just a small amount, are actually the single largest source of pollution in our waterways.”
The project is a cost-effective way for municipalities and homeowners alike to stop pollutants from entering streams, wetlands, lakes and marine waters while limiting the need for piping and other drainage systems, Block said.
“They really work well and they aren’t that difficult to create,” he said. “They can range between a few hundred dollars to a few thousand dollars, depending on how big the area is. There is government money available to help offset that cost. This really is cost-effective as government entities try to pay for runoff infrastructure and sewer systems. Rain gardens can take care of that problem.”
The more rain gardens that are installed in a single area or neighborhood, known as rain garden clusters, the more effective they are at combating contaminants, Block said.
“With this partnership with WSU … we know that we have the latest and best science working with us as well,” he said. “We really try to ensure all projects are done correctly with best possible information so we have the rain gardens project at its peak. The 12,000 rain garden campaign is a chance to put the Northwest on the map to be a national model for this.”
On the web
Read the Rain Garden Handbook for Western Washington Homeowners and watch an instructional video at www.12000raingardens.org to get started on your own project. Register your rain garden at www.12000raingardens.org/register.html.
Implement your own garden
-Identify the best location for the garden
-Test the soil
Step two — Design and build
-Determine size, shape of garden
-Level bottom of garden
-Mix compost with soil
-Place soil mix, leaving 6 inches below edge of garden for ponding
-Level surface of soil
-Create water entry
-Provide rock-lined overflow
Step three — Plant
-Use variety of small trees, shrubs, herbs or grasses
-Select plants that have appropriate water needs
-Cover exposed soil with 2 to 3 inches of mulch
-Water to establish plants
Step four — Maintain
-Mulch as needed to prevent erosion, weeds
-Keep clear of debris
-Don’t fertilize or use pesticides
-Water as needed