Improving water quality on North & South Center

The Minnesota Board of Water and Soil Resources did a comprehensive evaluation of North and South Center Lake water quality in 2019. Check out the article and video the BWSR put together with their findings!

‘Our water is our diamond’

As the cumulative effect of urban and rural conservation practices improves water quality, two lakes in the Chisago Lakes Chain of Lakes move toward removal from the Impaired Waters List. The Chisago SWCD’s work with landowners is backed by lake improvement district matches, Clean Water Fund grants and NRCS funds.

Barb Peichel, a Minnesota Board of Water and Soil Resources clean water specialist, looks at South Center Lake during a July 30 visit highlighting Chisago Soil & Water Conservation District projects accomplished through Clean Water Fund grants. Project partners have included the Natural Resources Conservation Service, the Chisago Lakes Lake Improvement District and the St. Croix River Association

CENTER CITY — On a hot summer weekday, a boisterous group of swimmers splashed near a private dock as the occasional boater crossed South Center Lake. On the opposite shore, a couple of anglers fished from Loren’s Park.

There’s a good chance none of them knew South Center Lake is on course to come off the Minnesota Pollution Control Agency’s impaired waters list as soon as 2022.

What residents and visitors do know is that water quality has improved.

Whether they live there or it’s a recreational cabin or getaway, they care about the lake the same. … They’re well-used and well-loved.

Casey Thiel, Chisago SWCD

From 2013 through 2018, phosphorus levels in both South Center and North Center lakes consistently surpassed water-quality standards for aquatic recreation. (Phosphorus feeds the algae that can turn lakes green.) Average Secchi disk readings, which measure water clarity, hovered at the threshold. Average chlorophyll-a levels, which indicate algal growth, remained high.

Left to Right: Casey Thiel, Jill Behnke, Craig Mell, John Olinger

“Things have definitely gotten better, and they’re getting close to the point where we can delist specifically these two lakes,” said Lee Engel, MPCA water quality monitoring supervisor. “You can see that concentrations are trending in the right direction.”

The 2018 results arrived in late January.

For the first time since the listing, South Center Lake came in under the threshold for chlorophyll-a. The 2018 average reading was 8.6 micrograms per liter. The threshold is 14 micrograms per liter. South Center Lake’s 2018 average readings for all three indicators were the best they’ve been since being listed.

Nine lakes in the 20-lake Chisago Lakes Chain of Lakes were listed as impaired in 2008.

Ten years and more than $2.2 million in water-quality improvement projects later, the Chisago Soil & Water Conservation District’s work with landowners and cities appears to be paying off.

“People are seeing the lakes improve. I hear that a lot from people,” said Casey Thiel, Chisago SWCD water resource specialist. “The fishing’s better. There’s less invasive plants. There’s more water. Water levels are a big issue. And then, ‘Hey, we haven’t seen that algae bloom that we usually get,’ or ‘We only saw one of those.’ People are noticing that.”

In Lindstrom, new or rebuilt city streets are made narrower when possible — a strategy that reduces storm water runoff and cuts city maintenance costs. Linden Street was made narrower where it dead-ends at South Lindstrom Lake. It’s flanked by a storm water treatment system that includes rain gardens.

SWCD staff credits the cumulative effect of water quality projects large and small.

Implemented over the past decade in three cities and four townships, those conservation practices include 88 rain gardens, 21 water and sediment control basins, 13 lined waterways, 10 storm drain inlet protections, nine vegetated swales, eight shoreline plantings, eight grassed waterways, seven gully stabilizations, four iron enhanced sand filters, three storm water pond retrofits, two diversions, a livestock access control, one wetland restoration, enhanced city street sweeping and a long term hay planting.