Plaster Creek Stewards and over one hundred volunteers completed eight curb-cut rain gardens last weekend.

Volunteers from local high schools and churches joined Calvin College students and Plaster Creek Stewards for a presentation and planting last Saturday morning. “We did get a lot of students,” said Andrea Lubberts, the Program Assistant for Plaster Creek Stewards. “Our biggest turnout yet!”

These volunteers split into eight groups, and each group tackled one curb-cut rain garden in the Alger Heights and Oakdale Heights neighborhoods. Site leaders, mostly past research assistants who are familiar with curb-cut rain gardens, led groups on site in laying rocks, mulching, and planting. Program Coordinator Deanna Geelhood selected the sites, delivered plants and tools to the site and coordinated the site leaders.

The heavy rains later in the weekend washed out some of the gardens, carrying some of the plants down the street according to one homeowner. The overflow is actually helpful, said Julie Wildschut, the Program Engineer for Plaster Creek Stewards. The washed out areas show where the flow of water enters a rain garden, so the team can go back and replant/rearrange the garden to put another rock basin into the layout, according to Wildschut.

The curb-cut rain gardens go in the parkway, the grassy space between the road and sidewalk. Using buckets and shovels, volunteers spread mulch over the soil and compost. Mulch traps heat and moisture, ensuring the survival of the small plants. Volunteers spread rocks to make a channel and basin in the parkway; these rocks absorb the energy of water as it flows into the rain garden from the street.

Due to the high concentration of impervious areas in the watershed, – roads, driveways, parking lots and foundations for buildings, Plaster Creek receives too much water. High volumes of rainwater also run off lawns, channel into the street storm drains, and eventually end up in Plaster Creek. Rain gardens are designed to divert water from reaching the creek. An opening in the concrete curb redirects the flow of water into the rain garden, where the water fills the garden and filters into the ground.

The native plant species transplanted into the garden also help with sequestering rainwater. The extensive and deep root systems of native plants turn the ground into a sponge, said Dave Warners, a Professor in the Biology Department and Co-Founder of Plaster Creek Stewards. These roots help water percolate into the soil by “poking holes into the ground”, Professor Warners said.

Before groups left to spread rocks, distribute mulch, and plant the gardens, Professor Warners and research assistant Patrick Jonker discussed their research on the success of rain gardens installed during the summer of 2015.

Jonker presented his research from this past summer in which he studied the success of the plants in the curb-cut rain gardens. Jonker collected data on the number of plants, number of leaves, number of buds, number of stalks, and amount of spreading. The data on each plant factored into a general scale from 1-10 assessing the overall performance of the plant: “10 being it looked incredibly healthy and was spreading, 1 being unhealthy and dying” Jonker said.

Through his research, Jonker concluded that using compost in the gardens made all the difference in plant performance; gardens with the higher plant performance were the ones that received compost to compensate for the sandiness of the soil. While Jonker’s research with Professor Warners answered some questions, their study also created many more questions for future summers.

Each rain garden, Professor Warners said, is one small thing that helps Plaster Creek. He calls them “nits and nats” – the little things, the small efforts, the extra steps. In his presentation, he explained the multiple benefits of rain gardens in communities. In addition to filtering water through the ground, the native plants also attract native species of insects and birds, boosting the biodiversity in each neighborhood.

While rain gardens are beneficial for the environment, Professor Warners recognized that not every house needs a rain garden. The goal of the rain gardens is to return to the estimated pre-development volume of water.

The rain gardens installed have already begun to do their job, as Professor Warners pointed out using a hydrograph depicting the ‘before rain gardens’, ‘pre-development’ and ‘after rain gardens’ water volumes. To reach the pre-development volume, the number of rain gardens “amounts to about one rain garden every eight houses”, said Professor Warners.

A few faces of Plaster Creek Stewards have changed this year. Mike Ryskamp, who had been the Program Coordinator for the previous four years, began a PhD. program at Michigan State University in Restoration Ecology, according to the Plaster Creek Stewards Summer 2016 newsletter. Deanna Geelhood, class of 2016, filled the position of Program Coordinator for

Plaster Creek Stewards.

Plaster Creek Stewards was recently awarded a grant to begin work on installing 20 more rain gardens in the Alger Heights neighborhood and 20 gardens in the Oakdale Heights neighborhood. The installation of these rain gardens will begin next spring.

By the numbers:

14 rain gardens in 2015

12 rain gardens in 2016

8 rain gardens on Sat. Oct. 15

+100 volunteers on Sat. Oct. 15 from

4 local schools groups

3 church groups

2,300 plants planted on Sat. Oct. 15