Water, water all around

With Massachusetts’ drought officially over as of May 10,  I’m feeling more comfortable about watering my garden. 

Nice to see rain on the hostas

I’m happy when it rains, even though some of my annual plants, most noticeably the tomatoes, are slow to take off this spring because of fewer sunny days. 

     With plentiful rain comes other problems, though. During last week’s heavy rain, water streamed down the street in front of our house toward the storm drains.

Rainwater heading for the storm drain

    Rainwater running off roofs and down driveways in our neighborhood could be carrying toxic chemicals from both surfaces into storm drains and through them to rivers and Boston Harbor. The EPA, the Massachusetts Department of Environmental Protection, and local government all advocate keeping rainwater at home, not letting it wash into the street.

     Our section of town backs up against the Charles River, which is one of our area’s most beautiful and prized natural resources. 

A quiet spot along the Charles

Years of effort have gone into restoring it from a toxic waste stream to a place where people and wildlife can enjoy the benefits of clean water. 

     At this point, storm water runoff is most of what pollutes the Charles by carrying oil, grease, gasoline, pet waste, detergents, pesticides, fertilizer, and trash into the river. 

Overgrowth of algae in a river caused by fertilizer runoff

Rain should be soaking into the soil to replenish groundwater, but with more areas paved or covered with lawns that slope toward the street, it flows into storm drains instead. 

     Not wanting to be part of the problem for the river, in 2013 we agreed to install two 14-foot strips of porous paving in our driveway. One runs from a downspout at the corner of the house toward the street. The other crosses the width of the driveway alongside the sidewalk. 

     This material looks like asphalt but allows water to flow through to a layer of crushed stone which holds the water while it gradually percolates into the subsoil. When it rains, we can see that water no longer flows down the driveway into the street. As the water reaches the porous paving, it disappears into the ground.

Water drains through the darker porous paving

     Our sandy soil drains fast. We never see flooding in our yard. Rainwater falling on soil sinks into the ground and doesn’t flow toward the neighbors’ paved parking area behind our lot. So the porous paving in the driveway is enough to prevent storm water from running off our property.

Rainwater doesn't flow off the berm at the back of the yard

     Rainwater streaming from downspouts and driveways into the street now looks to me like a waste. Instead of watering with purified tap water, we could be collecting storm water and using it in our gardens. I calculate that the rain falling annually on our 1,900-square-foot roof could supply just about all the water I use for irrigation. 

     So have I been harvesting water that falls on the roof? No, I’m sorry to say I haven’t. The obstacles are cost and the prospect of digging a huge hole in the garden for an underground cistern. Maybe 

someday. Meanwhile, I’m enjoying the irrigation that’s falling from the sky.

Diverting some rainwater with a rain barrel