What is a Rain Garden?
A rain garden is a small garden planted with native shrubs, perennials and flowers in a small depression. The intent of a rain garden is to temporarily hold and soak in rain water runoff from lawns, roofs, driveways or patio’s. Rain Gardens are very effective in removing up to 90% of nutrients and chemicals, as well as up to 80% of sediments from rainwater runoff. Compared to a conventional lawn, a rain garden allows for up to 30% more water to soak into the ground.
Rain Gardens should not be confused with a water garden, pond, or wetland as they normally remain dry most of the time. They will typically hold water only during spring runoff and after a rainfall event. Because they remain dry, they are NOT breeding grounds for mosquitos
What is a Swale?
A swale is a shallow channel that slows water down, spreads it out and allows it to sink into the soil during low flows. If the swale becomes saturated, excess water is transferred to a safe outlet through a grate that flows excess water to storm drains.
There are two types of swale systems, either vegetated or rock lined, sometimes called soakaways or dry creek beds.
Rock Lined Swale
Vegetated Swale
What is a Berm?
A berm is a low, earthen ridge around three lower sides of the rain garden that holds water temporarily during rainstorms, and keeps water from escaping into other areas.
Logging Requirements
To Log this Earthcache
Please send me your answers within 4 days of posting your found log. If there is more than one cacher in your party, include the names in your group. Only one person needs to send me the group answers. No spoiler photos, please. Found logs posted without proof you visited the site will be deleted.
At the posted coordinates you will find an example of a rain garden as part of the Green UP Ecology Park. You will also walk a short distance to the Gazebo which is stage 2.
Questions
Stage 1. Sign and rain garden
- According to the sign, Rain gardens are sunken gardens designed to ______________, ________________, and __________________ rain water that runs off from impermeable surfaces on your property such as the roof, driveway or patio. ( three words)
- From the list of native plants suggested to plant in your garden, name 4 that you would select for your garden
- Looking at the rain garden planted just beyond the sign, and from the information in the cache listing, would you say this is an example of a rock lined swale, a vegetated swale or a combination of both.
Stage 2. near Gazebo
- Look at the small U shaped berm surrounded by flat stones and open on one end to capture runoff from the vegetated part of the garden. Do you feel that this feature is doing its job to capture excess rain and filter it back into the groundwater? At the time of your visit, was this depression dry, damp in spots, muddy or filled with water?
