City of Madison

City of Madison Engineering | Photo Credit: Archie Nicolette



City Engineering is currently offering rain gardens in terraces in conjunction with street reconstructions and resurfacing projects, where they are appropriate.

Streets need to have terraces that meet the following criteria to be considered eligible:

  1. Terraces must be at least 10 feet wide;
  2. There must be at least 15 feet in length available for a rain garden;
  3. Trees must be at least 10 feet from the edge of a rain garden;
  4. Terraces cannot be too steep (in any direction);
  5. There cannot be issues with high groundwater;

As long as these criteria are met, we will offer cost-sharing to homeowners who are interested in participating in this volunteer program. We continue to strive to improve and streamline this program each year, and the interest has continued to grow. In 2011, we will more than double the number of terrace rain gardens, for a total of 80 installed since 2005.

Click on the image below to see our general terrace rain garden specifications.

Rain Garden Site Suitability Form



Regarding planting, homeowners have one of two choices. They may either pay a portion of the total cost of hiring a contractor to plant the garden, or they may plant the garden on their own. If a homeowner chooses to use a contractor, their plant selection is limited to one of several city-designed rain garden planting designs, which can be found here. If a homeowner would rather design his/her own rain garden planting plan, the total cost of plants and all labor is his/her own responsibility.

Even if a contractor is used to plant the garden, all maintenance following the initial planting is the responsibility of the homeowner.

Should a homeowner sell their house or decide that they no longer want a terrace rain garden, the gardens are designed so that they can be filled in by the homeowner and reseeded with turf grass.



curb cut allows water to enter the garden

Water enters rain garden through an opening in the curb

Image: Fox/Keyes terrace rain garden

Newly planted terrace rain garden along Keyes Avenue, July 2009

Image: Fox/Keyes rain garden during rain event

Rain garden doing its job

Rowley Avenue terrace rain garden

Pilot terrace rain garden on Rowley Avenue