Friday, December 8th, 2017
Some progress reported in cleaning up Grand Lake
By Ed Gebert
GRAND LAKE - Officials say they're starting to see some progress after a decade of effort to clean up Grand Lake.
"Since about 2008, there have been a couple of things that really stand out. Our mutual loads or concentrations in the streams have dropped," Stephen Jacquemin, associate biology professor and research coordinator at Wright State University-Lake Campus, said at a Thursday news event. "They've dropped at low flows. They've dropped at medium flows. They'e dropped at high flows. These things are all good, but let's ask ourselves 'how good?' To ask yourself that, you have to scientifically monitor, and that's been what I've been very proud to be a part of."
Jacquemin and his team conducted a study in summer and fall to determine the effectiveness of the treatment trains installed on tributaries into Grand Lake. He said the results have shown a reduction in nutrients.
"Overall, when you focus just on the winter period, we see the reduction of close to 40 percent. We've seen a reduction of 50-60 percent in particulate phosphorus. We've seen a reduction of 20-40 percent in dissolved phosphorus We've seen a reduction of 20 percent in nitrate level. This is great news," Jacquemin said, speaking at the Greater Grand Lake Region Visitors Center. "When we look at the water quality before and during the winter period, we've got a home run on our hands. It's a huge reduction, and this is because of the adoption of the rules, regulations and the voluntary adoption of some of the best-management practices by producers in our region."
The study marked the first quantifiable results of the effectiveness of treatment trains, which had been built to remove the nutrients that can spur the growth of toxic algae in the lake.
The two active facilities have shown vegetative filters remove nitrates and phosphorus from the water.
Jacquemin also said he had additional good news to share aside from the success of the treatment trains.
"This is a watershed that has a huge amount of nutrient-related issues. We know this. It's one of the most nutrified systems not only in Ohio but also one of the most nutrified lake water sites in the country. Grand Lake has become kind of a fixture for water-quality issues," Jacquemin reminded the audience. "And I'm very proud to be able to say that over the last almost decade or so … it has also become ground zero for water restoration efforts to try to improve and clean up water quality."
The Grand Lake Watershed about 10 to 15 years ago ranked in the 90th percentile, he noted, in terms of nitrogen and phosphorus concentration in both the lake and its tributaries.
"This comes from a small watershed, and it's a watershed that's primarily agriculturally based, a large amount of runoff from livestock production," he said. "The watershed produces about one and a half times more phosphorus and two times more nitrogen every year than can actually be applied. It's a perfect storm for putrefication."
In 2011, a series of mandatory and voluntary management regulations and best-management practices were undertaken by area ag producers. They were required to have a nutrient-management plan, a written document that allows a producer to know the amount of nutrients being applied based on the soil's needs.
"It's a plan formed by science," Jacquemin explained.
More than 95 percent of the land now is on a nutrient plan, compared with less than 25 percent prior to the distressed watershed declaration.
Area farmers also face a wintertime ban on applying manure, which can run off fields into the watershed and add nitrogen and phosphorus to the water. Manure cannot be applied to frozen ground between Dec. 15 and March 1 or to snow-covered ground.
Lake Restoration Committee Chairman Tom Knapke hosted the event, which also featured Theresa Dirksen, Mercer County Ag Solutions coordinator.
According to Dirksen, other best practices being implemented include having huge numbers of cover crops planted, grass water strips, water with excess manure being transported out of the watershed and structures being built to store manure.
The monitoring of the treatment trains will continue increasing their capacity by running more water from the tributaries into the current littoral filters.
Grand Lake has a long way to go before being restored, but Jacquemin said he is encouraged by the effectiveness of the steps already taken, and the LRC is already looking to expand the filtering capability on the Beaver Creek Treatment Train, which should open next summer and on the Big and Little Chickasaw creeks. That facility is still in design stage but could be ready for use by 2020.
"We didn't get into these issues overnight, and we're not going to get out overnight," Jacquemin concluded.