Storm Water Management

Working in conjunction with the Metropolitan Sewer District, the Zoo is working to reduce its storm water discharge through the use of pervious pavers, green roofs, rain gardens, and bio-retention. For example, a large retention tank buried beneath the Historic Vine Street Village collects and stores up to 10,000 gallons of rainwater at a time.

Pervious Pavement

In big cities, up to 30% of the land surface is covered with pavement. We walk on it. We drive on it. We park on it. When it rains, water from traditional roads and parking lots runs off into the landscape and sewer drains, causing water pollution and flooding.

Pervious pavement allows rainwater to seep through it instead of forcing it off the edges. Water passes through tiny holes in pervious concrete or spaces between pervious pavers and is temporarily stored in a gravel layer below.

Zoo Pavement

More than 30,000 square feet of pervious pavement was laid in the Historic Vine Street Village, which can store about 500,000 gallons of storm water at a time. Overflow is directed into our elephant moat, which essentially acts as a large retention basin. Pervious concrete and pavers were also used to create the path in the Go Green Garden.

Go Green Challenge: Pervious Patio

If you renovate or create a patio, path, or driveway, use pervious pavers or concrete to reduce rainwater runoff. (Photo: Shasta Bray)

Find out more about pervious pavement

Rain Gardens

In a rain garden, plants are grown in a low spot designed to temporarily collect rainwater from downspouts and pavement. Rainwater that the ground does not soak up runs off into streams and sewers, picking up dirt and other pollutants along the way. Runoff can cause flooding, sewer overflow, and polluted water. By collecting rainwater, a rain garden reduces the amount of runoff that goes directly into streams and sewers. A rain garden also purifies the water as the root systems of the plants filter out dirt and other particles before releasing it deeper into the soil. Like other gardens, a rain garden provides a pleasing landscape as well as a habitat for wildlife.

The Zoo’s Rain Gardens

Check out the Zoo’s rain gardens in the Go Green Garden, in front of the Harold C. Schott Education Center, and in the Vine Street parking lot. Rain gardens are a relatively new method of storm water management in our region. The Zoo has some of the most visible and diverse rain gardens in the region and is a teaching garden and provides a model for other institutions. It is also a test garden, information from which will help determine the best practices for creating rain gardens in our area.

Go Green Challenge: Grow Your Own Rain Garden

For help creating your own rain garden, consult Rain Gardens for Southwest Ohio: A Practical Handbook for Home Gardeners (which was co-authored by the Zoo's Director of Horticulture, Stephen Foltz) found on the Hamilton County Soil & Water District’s web site at www.hcswcd.org.

Find out more about rain gardens

Green Roof

In place of traditional roofing, a green roof is topped with live plants. Growing a green roof has many advantages.

Reducing Runoff - Retaining up to 75% of rainwater, a green roof reduces the amount of water that picks up pollutants as it flows across the land and into natural bodies of water, known as storm water runoff.
Flood Control - Another benefit of retaining water is the prevention or reduction of the impact of flooding.
Cleaner Water - A green roof filters pollutants from the water, which is returned to the atmosphere through transpiration and condensation.
Cooling Off the City - Traditional roofs absorb the sun’s energy and re-emit it as heat, making the city up to 7ºF hotter than rural areas. Green roofs reduce this urban heat island effect by retaining the heat.
Cutting Down on Heating and Cooling - A green roof insulates the building during winter and keeps it cool during the summer, reducing heating and cooling loads by about 25%.
Keeping it Quiet - Acting as a sound insulator, a green roof reduces the amount of outside noise that is heard inside the building.
Cleaner Air - A green roof takes carbon dioxide out of the air and releases oxygen.
Longer Lifespan - A green roof protects the underlying structure from UV radiation, heat, and puncture damage, increasing its life span by two or three times.
Easy to Care For - Just the occasional weeding and watering is all it takes to maintain a green roof
A Place for Wildlife - Many birds and insects will take advantage of the habitat provided by a green roof.
It’s Pretty - A roof covered with plants is much more visually appealing than a traditional roof.

Giraffes Gone Green

The Zoo’s Giraffe Ridge building has a 2,400 square foot green roof, planted with a variety of sedum and other plants. It is one of only a few commercial green roofs in the city. The roof is a test garden in that we are studying which plants are the most appropriate to plant on a green roof in our region. By reducing the rate and volume of storm water that enters the sewer system, the green roof helps alleviate the city’s sewer overflow problem.

Go Green Challenge: Encourage the Green Roof Movement

Encourage companies and businesses in your region to plan a green roof into any new construction plans. Learn more from Green Roofs for Healthy Cities.