Photo Galleries
Rain Garden and Driveway Trench PEA 2016
SOAK NH partnered with Phillips Exeter Academy for their Climate Action Day 2016 to teach students about stormwater runoff and ways to address it. Students helped build a rain garden / driveway infiltration trench project to soak up the rain on campus. This is the rain garden one year later after a storm.
The project area. Rain from the road, driveway, and roof was eroding the lawn and traveling down the road to a catch basin system that dumped out in the Squamscott River.
Another view of the project area. Trenches were built on the end and side of the driveway visible here and rain was captured from the downspout on the corner of the main house. The eroded hillside is in the foreground.
The first step to installing a rain garden is to plan the shape. A garden hose is a handy tool for this job!
The driveway trench were excavated with a backhoe. Students then lined the trench with geo-textile fabric which prevents soil from migrating into the trench and taking up pore space need for water storage.
The driveway infiltration trenches are filled with 3/4 inch drainage stone then topped with larger decorative stone.
The students performing a soil ribbon test to determine the type of soil - sand, silt, or clay - in the rain garden area.
Stakes in the garden and along the berms are used to measure and level the garden bottom and berms. This helps form the "kiddie pool" shape of the rain garden so it can hold water and allow it to soak into the ground.
Once the stakes are marked at the intended berm height, string is tied from stake to stake and the berm is built up to the string.
The rain garden area is prepped and ready for students to begin installing the planting bed, constructing the overflow outlet, and then finally planting the rain garden shrubs and perennials.
Students dug a trench from the downspout to the garden to bury a downspout extension. This is how water is delivered from roof to the garden.
PEA students are proud of their hard work! The end of the downspout extension pipe is disguised with large flat stones.
At the end of the downspout extension, a stone area is built to help the rain water disperse as it enter the garden.
Three happy students learning how much soil has to be moved in order to build a rain garden! The students created a nourishing planting bed by mixing composted soil and other needed amendments with native soil.
PEA groundskeeper Bernadette giving a lesson about how to plant.
PEA students planting perennials according to Bernadette's instructions.
Planting on the sloped sides of the rain garden help stabilize the slopes when the rain garden fills up with rain water.
Completed project shortly after it was built.
The project site one year later indicates the driveway infiltration trenches and rain garden are doing their job to capture rain water.
One year later the rain garden plants are filling in nicely!
The overflow outlet directs the water out of the garden for very large or intense storms when the garden fills up faster than it can soak in.
The partially filled rain garden after a storm the year after it was built.