Household Hydrology

July 2008

The recent spate of rainstorms has given me ample opportunity to figure out where winter’s snow and ice have damaged the gutters around my house. Water pours from cracks between channel sections, or where the clip hangers have been bent. Just a little attention and time can usually alleviate the problems. However, looking around at many other houses it is clear that gutter systems do not always receive much attention. I see seedlings growing in clogged gutters or gutters without drainpipes or drainpipes attached to nothing. I guess not everyone pays attention to their household hydrology.

Hydrology, in short, is the study of water, its movement and distribution. Household hydrology therefore focuses on how water moves around your own living space. 

Consider how humans’ living areas change hydrology. We build structures that keep us dry by shedding water. We harden surfaces, driveways and sidewalks, to make them easier to walk or drive upon. We install sump pumps in cellars to move water out of our homes. We dig ditches that convey water off our property as quickly as possible. When such changes are summed over an entire neighborhood or city the effects can be tremendous. Small streams are forced to carry excess water during storms, resulting in erosion and downstream pollution.

There are steps homeowners can take to limit downstream impacts. Mostly they involve finding creative ways to keep the water that lands on your property from leaving it too quickly.

Gutter downspouts should be the first focal point. Simply ensuring that downspouts discharge onto the lawn rather than a driveway or walkway helps. Discharging onto grass gives the water a chance to soak into the ground before running off. 

Alternatively, the first flush of a storm can be captured in a rain barrel placed beneath the downspout. Rain barrels can be purchased or built, and they come in a variety of sizes. The barrels effectively hold water until it is needed for gardens, flower beds or other uses. I have even seen variations on rain barrels used for collecting roof runoff of large commercial buildings. Mosquitoes, the main concern with rain barrels, can be kept out with protective screening. Attractive, painted barrels can add a festive addition to a lawn’s décor. 

For those willing to invest a bit more, rain gardens can be an attractive way to deal with your household hydrology. Rain gardens are landscaped low spots in the lawn created for collection of water from driveways, roads walkways, or downspouts. They are typically four to eight inches deep with a berm on three sides to prevent water that enters from escaping. They should be placed at least ten feet from the house to prevent water seeping through the foundation. 

The greatest expense in building a rain garden is the plants that will be placed there. Plants need to tolerate wet periods and dry periods between storms, and may include ferns, sedges, perennials, or shrubs according to taste. Plantings should include a mixture of heights and blooming times so the rain garden looks good throughout the growing season.

In a properly designed rain garden, water pools for only a few hours before filtering into the soil. This prevents mosquitoes from breeding. However, it also means rain gardens should not be located over septic systems or existing wet areas where drainage is poor. Additionally, for a given volume of water, the gardens need to be larger in areas with heavy clay soils.

Once built, a rain garden generally requires minimal maintenance. They need to be weeded and watered in the first few years, and perhaps thinned out and mulched as they age. SeaGrant provides a step by step guide for building a rain garden in the Champlain Valley including a good list of appropriate plants at Lake Champlain Sea Grant's website. 

With just a little effort and attention, managing household hydrology can improve the condition of our streams and lakes while simultaneously enhancing the appearance of your home.