The Beautiful Solution to Water Pollution

A few years ago, Patricia Pennell was introduced to the concept of rain gardens while talking to some people in Prince County, Maryland. Her brown eyes widened at first, then narrowed shrewdly.

At the time, Pennell was coordinating the stream protection program at the West Michigan Environmental Action Council and always on the lookout for new ways to engage volunteers in the effort to cleanup area waterways.

Rain gardens, she concluded, were the next big thing. Since then, Pennell has almost single handedly elevated metropolitan Grand Rapids as a center for rain garden knowledge and innovation. Due in large part to her vision and hard work, the region boasts dozens of successfully functioning prototypes. People from across the nation regularly look to the area for new information and techniques. And photographs and articles about Pennell’s gardens have appeared in a number of local and regional publications, including Midwest Living.

Schools and public buildings have installed them. The city now employs them to solve drainage problems. Developers feature them in new construction, to much media hoopla. A major university in Kalamazoo has built them. Even a condominium association in Pentwater has one.

Put simply, thanks to Ms. Pennell, rain gardens are increasingly embraced by citizens, public officials, and home builders throughout the region as the standard way to manage water and keep it clean. And the nation, if not the world, is paying attention. Don’t believe me? Google the term ‘rain gardens’ and you’ll find that Rain Gardens of West Michigan, Pennell’s Website, is the number one result.

“Our water resources are something to be treasured,” says Ms. Pennell. “The focus of my work is to improve and protect water quality in the streams and rivers of Michigan, and to empower and educate others to do the same. When streams are healthy for the creatures that live in them, they are likely to be a healthy place for people to live, too."

So what is a rain garden? And why are they important?

For starters, they are much more than landscaping. Rain gardens are valuable assets that absorb and store the storm water that runs off rooftops, parking areas, and other surfaces. Acting like kidneys, they also help to purify the water and allow it to percolate back into the soil. They are designed to be free of mosquitoes, inasmuch as the water-return process outruns the ability of the mosquitoes to hatch. With native plantings, they also are designed to be beautiful and low-maintenance.

To the eye, they are designed like gardens. But at the subterranean level they are engineered to reduce the flood of polluted surface water that typically flows off man-made surfaces into our streams and rivers every time it rains. (Any detailed conversation about rain gardens with Pennell, an environmentalist, is sprinkled with references to technical terms like soil compaction, infiltration rate, retention capacity, and French underdrains.) And all the rainwater that they collect is delivered directly into the ground, rather than into the urban storm sewers through the storm sewer gratings along city streets.

We’re not talking here about the sanitary sewers, which process sewage. We’re talking about storm sewers, which are essentially collection pipes that gather fresh rainwater from dirty surfaces such as streets and parking lots and deposit it into the river, incorporating no pollution treatment effort of any kind.

Urban stormwater may generally be described as a thin broth, made up of rainwater, petroleum products, heavy metals, pet droppings, Big Gulp cups, fertilizers, pesticides, eroded soils, and many other secret ingredients.

Sometimes the broth is chilled. But sometimes it’s warm or even downright hot, depending on the weather, the pavement, and the amount of rainfall.

As I reported in a recent column, the City of Grand Rapids is one of the nation’s leading midsize cities in terms of keeping its raw sewage out of the environment. (Even though downstream communities like Grand Haven don’t want to believe it.) In the last twenty years Grand Rapids has spent over $100 million to modernize its sewer system. As a result, the city has eliminated 98 percent of its sewage overflows. We’ll eliminate the remaining 2 percent in the coming years.

Ironically, some of the solutions to our sewage spill dilemma make our stormwater pollution worse. Storm and sanitary sewers increasingly are separate systems so, today, stormwater that once went through the sewage treatment process now goes directly to the streams without any treatment at all.

That means stormwater pollution requires a different strategy: one aimed at prevention instead of treatment.

Rain gardens are not the only strategy to manage and clean stormwater. But, thanks to Ms. Pennell, they are the strategy that Grand Rapids is best known for. Her website turns up at the top in a Google search for “rain gardens.” But any number of runners-up – Kansas City, Wisconsin, Minnesota – are working tirelessly to displace her. She has provided technical assistance to a lot of these outfits, and her words and photographs appear under many organizational banners.

So far as I know, Pennell pioneered locally the idea of using primarily native Michigan plants in her rain gardens. In so doing, she cuts the costs of garden maintenance (since native plantings tend to like the conditions here) and simultaneously launches lifeboats for increasingly rare Michigan plant species.

Philanthropy has played a significant role in building GR’s reputation as a rain garden pioneer. Early investments by the Grand Rapids Community Foundation, Frey Foundation, Steelcase and other funders have led to remarkable economic and environmental benefits.

But growing community apathy, and the funders’ wandering attentions have left the program stranded. American Rivers, an environmental organization based in Washington, D.C., has tried to fill the gap. But the intermittent funding is not enough to cover the costs of Pennell’s increasingly important work.

Too bad. We will continue to install rain gardens here. They make too much sense. But I doubt we will continue to be Rain Garden Central if Patricia Pennell isn’t here to make us so.