by Jeanne Marquis

China Lake Association has announced the China Lakes Watershed-Based Survey has been completed and available to the public on their Website at https://www.chinalakeassociation.org/news.

The China Lake Watershed Survey systematically documented areas of soil erosion, ascertained the level of severity at each site and recommended viable solutions. The watershed survey is part of the Watershed-based Management Plan currently in development that will identify strategies for improving the water quality of China Lake over the next ten years.

The reason why the 2021 survey is relevant is the water quality of a lake is determined to a large extent by its watershed – the land that drains into the lake. The China Lake watershed extends 26 miles in Albion, Vassalboro and the towns of China. What happens on property anywhere in this area, even if the property is not in view of the lake, can eventually drain into the lake and impact water quality.

Scott Pierz, president of the China Lake Association, explains, “Historically, China Lake has been on the Department of Environmental Protection’s list of impaired waterbodies for such a long time. Algae blooms started to appear in the early 1980s.”

Soil erosion is a major contributor to quality issues because soil contains the nutrient phosphorus. Much of the phosphorus is naturally occurring in the soil from leached minerals or decaying organic materials. However, some phosphorus enters the soil from human practices such as phosphates in laundry detergent or from the application of fertilizers, both organic and chemical additives. Why phosphorus is potentially harmful to the quality of a lake is it feeds the algae causing a bloom depleting the water’s oxygen content. The lower oxygen level upsets the eco-balance, decreasing the overall water clarity and creating a dead zone that is not habitable by fish life.

The survey was conducted on October 3, 2020, as a project partnered by the China Lake Association (CLA), the Kennebec County Soil & Water Conservation District, China Region Lakes Alliance (CRLA), Kennebec Water District, Town of China, and Maine DEP. A team of local volunteers and technical leaders from the partnering organizations identified and prioritized 161 sites that were current sources of soil erosion and stormwater runoff on developed land within the watershed area.

They used standardized field data sheets and maps to indicate roads, buildings, driveways and stream crossings that were sources of soil erosion contributing to the polluted runoff into China Lake.

Each site was rated with a risk assessment of low, medium to high and recommendations for solutions were identified. Twenty sites were considered a high impact to the lake, 59 were medium impact, and the remaining 82 were low impact. The majority of the sites, 67 percent, were found in residential areas.

These sites tended to have less severe erosion issues that could be easily fixed at minimal cost. Seventeen percent of the sites were identified on private, state or town roads. The remaining sites were at lake accesses, commercial property, construction sites, driveways, public land and on trails. The China Lakes Association will reach out to all identified sites with recommended solutions. Project partners will seek grant funding to help cover costs, and the Youth Conservation Corps programs may be able to assist in erosion correction projects.

Pierz reminds us, “Every one of us, in some way, is impacted by China Lake’s water quality, and it’s up to us now to take action and do our part to help reduce stormwater impacts so that in the future we can all enjoy the beauty of China Lake, our recreational opportunities, and the wildlife that is so special to the environment in which we live.”

Since the 1980s when the algae blooms were at their worst in China Lake, considerable progress has been made due to the work of local and state organizations.

Pierz reported, “Regarding most recent trends, during the summers 2017 through 2019, China Lake experienced the best water quality in 30 years! This fact was corroborated through ongoing water quality monitoring completed by the Kennebec Water District during each of those summers. In 2020 water quality was down a bit, but we’re hopeful that all efforts provided by the CLA and CRLA programs, across time, will help heal China Lake.”