Poor drainage could be caused by various sources that we have little or no control over, including but not limited to gradual grades or low-lying areas, clay or other tight soils, or shallow groundwater. In other cases, controllable causes may also be a contributing factor, such as drainage from impervious areas such as roofs, driveways, and sidewalks, or irrigation systems, pools, and sump pumps.
Tips to Improve Drainage Issues
Position Runoff Appropriately
Make sure downspouts, pool drains, and sump pumps are directed away from structures like houses and garages, and preferably toward vegetated areas that are quickly able to absorb runoff. Adjust your irrigation system to allow for minimum run-time, and check for any leaks or malfunctions.
If you have a low-lying area in your yard that collects water which is only present for short periods (less than 10% of the growing season), and is at least ten feet from any structural foundations (basements, etc.), try turning this area into a garden or landscape feature with plants that are flood-tolerant. It may also be possible to capture the water higher up on the landscape and infiltrate it in a rain garden thereby keeping the lower lying area drier. The City does have small grants available to assist land owners who wish to install a rain garden on their property. Often the watershed district does as well.
Soils with high clay content are unable to absorb water (infiltrate) at a fast rate leaving puddles that last for hours. If your soil is high in clay content add organic matter to your soil. This will help water absorb into the ground more quickly. Covering areas with high clay content with organic materials such as compost or ground wood chips as mulch will also increase organic matter content over the years and soften the soil allowing for increased infiltration.
Plants such as typical turf grass and many ornamentals normally do not thrive in areas of poor drainage. However, there are numerous trees, shrubs, grasses, and flowering plants that do well in poorly drained areas. Some of these include, swamp white oak, river birch, American larch, red-osier dogwood, black choke cherry, buttonbush, high bush cranberry, several varieties of aster, butterfly milkweed, prairie cord grass, little blue stem and many more. Look for rain garden workshops hosted by the City or Watershed District and presented by Metro Blooms. Some sources for suitable plants include Plants for Stormwater Design and WSB Guide to Rain Gardens. Blue Thumb Guide to Rain gardens is available upon request by contacting Surface Water Resources Coordinator Matt Unmacht.
For a printable version of these tips click here.