Lake Hiawatha’s trash problem fed by culverts every rainfall

Since May, Standish-Ericsson resident Sean Connaughty has removed 62 bags of garbage from Lake Hiawatha.

That’s over 1,500 pounds of plastic cups and bottles, snack wrappers, cellophane, cigarette butts and more.

Photo right: In four months, Standish-Ericsson resident Sean Connaughty has removed 62 bags of garbage from Lake Hiawatha. After each rainfall, the lake is full again. (Photo submitted)

That doesn’t count the invisible pollutants such as lawn fertilizers and herbicides, ice-melting salt and automotive pollution that wash into Lake Hiawatha. From there it will travel into Minnehaha Creek, the Mississippi River and the city’s drinking water.

“With each bag of trash there are 1-4 syringes. I also regularly remove condoms and diapers, to name a few of the disturbing items,” said Connaughty.

“In addition to the environmental and ecosystem damage this is causing, it also poses a public health risk,” Connaughty pointed out. “With items such as syringes, diapers, condoms and all manner of pollutants regularly entering the lake, it is no surprise that there are regular beach closings due to high bacteria levels.”

The urge to pick up trash as he was walking his dog twice a day around the 55-acre lake began simply enough. But, as Connaughty’s concern about water quality grew, it has propelled him into a larger fight.

“Despite my best efforts to clean the lake and the efforts of the recent Minnehaha Creek Watershed District (MCWD) organized clean-up, the lake is once again full of trash from recent rainfalls,” observed Connaughty.

Lesson from a green ball

Along the way, Connaughty learned an important lesson from a green golf-ball-size ball.

Connaughty marked the ball and then dropped it into the storm drain. Two weeks later, he found the ball among the debris clogging the lake around the storm sewer culvert on the north side.

Photo above: To answer the question of where all this trash was coming from, Sean Connaughty marked a green ball and dropped it in the storm sewer. Two weeks later, he found it in Lake Hiawatha near the city’s large stormwater culvert that drains directly into the lake without any filtration. (Photo submitted)

“The storm sewer outfall on the north side of the lake is emptying enormous amounts of trash and pollution into the lake with every rainfall,” Connaughty remarked.

While many have believed that Minnehaha Creek is the primary source of pollution in the lake, Connaughty’s day-to-day observation of where trash is located has shown that the storm sewer outfall is the bigger problem.

Connaughty learned that this drainage system, going directly into the lake, includes a huge swath of South Minneapolis. “It drains debris, trash and other pollutants from our streets coming all the way from Chicago Ave. to the west and Lake St. to the north,” he observed. “This storm drain system has no filtration or mitigation at all.”

To share this knowledge with fellow residents, Connaughty began stenciling gutters with the outline of a fish and the reminder: “Please do not pollute, drains to the Mississippi River.” Connaughty has personally stenciled 175 gutters, and he was joined by a group in August organized by the Standish-Ericsson Neighborhood Association.

How to fix the problem

In addition to spreading the word about the pollution problem, Connaughty is pursuing other methods to prevent trash from entering Lake Hiawatha, Minnehaha Creek, and the Mississippi River.

He’s begun lobbying local political organizations, including the Minneapolis City Council, MCWD, and Minneapolis Parks and Recreations for infrastructure that will filter out pollutants before they enter the lake.

Along with a few others, he has proposed building an emergency catchment in the lake surrounding the storm sewer outfall. It would be constructed of natural materials and would create a porous barrier to capture the trash at the culvert. A strong trellis-like structure could accommodate the varying conditions at the lake without restricting the flow of water.

“This would be a way to localize the trash to make it easier and presumably less expensive to clean up, rather than having the trash spread throughout the entire lake,” explained Connaughty.

The emergency catchment could be implemented immediately once they receive permission.

A permanent solution would be changing the storm sewer infrastructure to create a catchment pond that can capture debris and pollutants before they reach the lake. Other lakes have these types of filters, including the “Lake Amelia” catchment ponds nearby at Lake Nokomis.

Golf course meeting Sept. 15

The timing on Connaughty’s suggestions coincides with the Park Board’s new vision of a more natural shoreline for Lake Hiawatha. Following the approval of a Master Park Plan last year, plans to modify the golf course are now underway after last year’s flooding.

“There is currently a once-in-a-generation opportunity to alter the storm sewer system that will occur when the golf course is restructured next year,” pointed out Connaughty.

He added, “Changing the storm sewer infrastructure would dramatically improve the water quality in the lake.”

Several others agree that now is a good time to find a fix to this problem.

According to Parks and Recreation Commissioner Steffanie Musich, “The city of Minneapolis, Minnehaha Creek Watershed District and Minneapolis Park and Recreation Board (MPRB) have been working to identify holistic designs for the course that not only retain golf playability at the site, but also help other park users gain greater access to the lakeshore, reduce localized flooding in surrounding neighborhoods, reduce pollution entering the lake via stormwater pipes and enhance the ecological function and storm water capacity of the creek.”

She pointed out that improvements upstream of Lake Hiawatha, including in the pipeshed, have the potential to reduce pollutants. The golf course improvements would only be a few pieces of a larger effort to undo the damage done to the creek and Lake Hiawatha by the development of modern stormwater conveyance systems. Those systems were originally constructed to prevent and reduce the flooding of homes and businesses in the cities the creek runs through.

A public meeting to collect feedback on the proposed designs will be held on Sept. 15, 6-8pm at the Nokomis Recreation Center Gym.

“Responsibility to leave it better than we found it”

MCWD Vice President Brian Shekleton praised Connaughty for doing a tremendous job expanding public knowledge about what happens to water flowing into the lake by using multiple tactics that draw attention to potential solutions. In addition to stenciling gutters, he is organizing neighborhood blocks to monitor streets for trash.

Shekleton pointed out that history and hydrology matter in understanding why Hiawatha is a polluted, or impaired, lake. A wetland complex that extended many blocks to the north and west of the lake used to filter water flowing into the lake. It’s now mostly homes in the Northrup, Bancroft, and SENA neighborhoods—and the golf course.

“Those water-cleaning wetlands can’t be replaced, but there are effective techniques to restore ecological functionality,” remarked Shekleton. “Things like filtering basins, architected wetlands, and re-meandering the creek come to mind.”

According to Shekleton, MCWD has many projects upstream that will benefit the lake, “but partnering with the MPRB and the Minneapolis gives us a chance to spend money most effectively by leveraging each organization’s specialties to better water quality in the lake,” he said.

Shekleton pointed out a similar partnership upstream that will benefit Lake Hiawatha. In St. Louis Park and Hopkins, tons of pollutants will be removed from Minnehaha Creek that now flow down downstream into Lake Hiawatha. This will happen by stopping storm pipes from dumping into the creek and filtering the stormwater before the water flows into the creek.

“I’m confident we’ll make Lake Hiawatha a cleaner and healthier body of water, particularly with the addition of natural filtration ponds through the golf course. This work will also help make the surrounding neighborhoods more flood resistant by increasing stormwater storage capacity,” said Ward 12 Council Member Andrew Johnson. “I love Lake Hiawatha, and we have a responsibility to leave it better than we found it.”

Connaughty observed that the parks, watershed district and golf course have only recently begun to consider making changes to the infrastructure of the culvert. “Whether this plan will be adopted or not is still quite tenuous. If this major outfall going directly into the lake is not addressed the garbage and pollutants will continue to impair this critical habitat, and the water quality will remain poor,�� Connaughty said.

“The city is the only entity involved in the negotiations that has the sole authority to implement an infrastructure change. Therefore, I recommend contacting the mayor and your councilperson to voice your opinion on this matter.”