i pull into work one hot, summer day in july and look over sharon lake. the small body of water sits within sharon woods park in northern cincinnati, ohio. the water is green and covered in duckweed, a native plant that can grow out of control and reduce oxygen levels and block sunlight.

on this hot july day, there are no ducks bobbing on the water, no turtles swimming, just green. as i stand there unlocking the door to the boat house, i can’t help but wonder what is happening to the fish, is the water green for them too? do the weeds block out the sunlight so much that they can’t see where they’re swimming? what about the plants underwater, can they survive in the green?

during the summer of 2024, the park began draining the lake and as of this fall, the lake is dry. this is thanks to the work of the ohio state-run organization, great parks of hamilton county which is currently draining and dredging the lake. the goal of the project is to restore natural wetlands in the area and kill off much of the duckweed that was plaguing the lake.

according to the brandywine conservancy, too much duckweed can lead to a reduction of available oxygen in the lake and reduce the amount of sunlight penetration which can decrease the growth of other lake vegetation. the duckweed also impacts the boating culture at the park. sharon lake is a popular kayaking location for those in the area, but the duckweed makes it difficult for visitors to traverse the water.

typically, this excessive growth is caused by a process called eutrophication. as described by encyclopedia of inland waters, eutrophication is an ecological process in which a body of water becomes over enriched with nutrients. these excess nutrients can lead to an increase in photosynthesis which can cause harmful plant blooms. if the reservoir was left alone, these algal blooms could become dangerous and harmful to people and animals. according to local experts, the excess nutrients at sharon lake are coming from agricultural and construction runoff.

amanda nurre, watershed specialist with great parks of hamilton county, said that the park does not own much of the watershed leading into the lake.

“unfortunately, we don’t control a lot of the watershed for this lake,” nurre said. “it’s like we have the lake, but we don’t own all of the areas that contribute water to the lake. so, it’s hard for us to do a lot of management outside of that, which makes (overall) management more difficult.”

to address the eutrophication, the park is dredging the lake. dredging is a process to remove sediment from the bottom of a body of water. according to the national oceanic and atmospheric administration, environmental dredging is typically performed to reduce and prevent the spread of contaminants to wildlife and people.

during the dredging process, however, the park decided to get a little creative. due to the  costs of trucking sediment out, the park decided to instead use the dredged sediment to help create surrounding wetlands. the sediment will be removed from different parts of the lake and put into sediment bags.

the removed sediment will decrease the available nutrients in parts of the lake which should decrease the duckweed. the sediment bags will be placed near the three main streams that flow into the lake to construct wetlands.

according to nurre, the goal is to create a border at these tributaries to “hold back some of the sediment coming in, and then we (park maintenance) should be able to more easily go in, more regularly, and clean the sediment out from behind.”

wetlands can help improve the water quality and help to filter the excess nutrients causing eutrophication. as noted in the book, wetlands by william mitsch and james gosselink, wetlands process and remove dissolved solids and nutrients from surface and ground water and can convert them into biomass, effectively removing them from the water. by adding wetlands to the reservoir, the ecosystem will benefit and become healthier.

these new wetlands will provide a habitat for fish, amphibians, and native plants. they will also add an aesthetic value to the park. visitors will now be able to see the new sharon lake and get to see new plants and animals at the park. part of the project includes a new boardwalk for visitors to observe wildlife from. local park-goer michael yuwono said he’s excited about the project.

“i think this project will definitely add to my visit to the park,” yuwono said. “because (the boardwalks) provide more opportunities for me to connect and learn about the nature that is abundant and alive in sharon woods.”

this dredging is just a temporary solution to the issue at sharon lake. there will still be construction runoff that enters the lake, and the lake is likely to experience that pollution for a long time to come. but this project still brings a lot of hope for the future of the lake. it will make it much easier for the lake to be cleaner in the future and will give the lake a chance to become healthier too. while it remains to be seen how effective the project will be, it is my hope that when i visit sharon lake in the future, i will see a flourishing ecosystem that benefited from this project.