DULUTH, Minn. --
DULUTH, Minn. - The U.S. Army Corps of Engineers and City of Duluth have a plan to remove debris placed on Minnesota Point during 2020 beach nourishment.
“Safety is a top priority for the corps of engineers,” said Corey Weston, Chief of Construction and Survey, at the Corps of Engineers, Duluth Area Office. “We take it very seriously and have from the beginning demonstrated our commitment to the city and community to resolve this issue.”
Last fall, after placing dredged material for beach nourishment on Minnesota Point, fragments of decades-old aluminum cans were found on the beach. The Corps of Engineers took responsibility for placing the aluminum fragments and have been working non-stop with the City on a plan to remove them.
The Corps of Engineers used ground penetrating radar to survey the area and find out the extent of the debris. The beach and nearshore zone surveys identified several areas of concentrated debris within the dredged material.
Two of these areas were likely at the end of the dredged material placement pipeline where heavy debris quickly settled out. The survey contractor conducted exploratory excavations in these areas. Most of the debris was rocks and wood, but it also included taconite pellets, some nails, and a small amount of other man-made debris. In all, the contractor found about a gallon of debris at these two sites. The aluminum can fragments, however, are lighter with a relatively large surface area, so they were likely spread out across the beach during placement operations.
Although overall the amount of debris is small compared to the volume placed, the Corps of Engineers remains dedicated to the cleanup. Together, the Corps of Engineers and City developed a multi-phase approach to clean up the aluminum fragments and concentrated debris areas:
To address the distributed aluminum fragments:
- The Corps of Engineers is expediting acquiring a mechanical beach rake to periodically rake the sand.
- The device will remove all debris, including trash not placed by the beach nourishment project, even down to cigarette butts.
- Each time the Corps of Engineers rakes the top layer of the beach, they will record how much debris is collected to help determine an appropriate interval and overall duration of raking operations.
- They expect raking to begin in August
- In the meantime, Corps of Engineers staff will continue walking the beach to look for and pick up any aluminum fragments, as they have done since they were first notified of their presence on the beach.
- Over the past nine months, Corps of Engineers employees and Park Point Community Club members have collected about a rolling household garbage can worth of aluminum fragments and other trash brought in by the waves and disposed of on the beach in an area the size of about two acres or a typical city block.
- The cans have been generally been found to be sparse and spread out.
For the few concentrated areas of debris, the survey identified:
- The Corps of Engineers plans to have crews begin excavating and screening the sand in those areas in mid-June, once required coordination with the City and other key partners, such as the Minnesota Pollution Control Agency, is complete.
- If Corps of Engineers crews are not able to fully remove the concentrated debris from those areas, they have an option in their 2021 dredging contract to complete the removal.
- Out of an abundance of caution, the Corps of Engineers worked with the City to place barrels on the beach, marking areas of concentrated debris that could potentially pose a risk to beachgoers. These barrels should not be disturbed.
To keep debris from being placed in this year’s and future dredging, the Corps of Engineers has incorporated additional measures in dredging and placement contracts. These include using a smaller screen size to catch debris, adding contract conditions to monitor material and stop production if debris is observed, and increasing Corps of Engineers’ oversight of contractor operations.
Additionally, the survey revealed erosion continues to be severe along Minnesota Point. Material placed in 2020 provided important shoreline protection, but a long-term solution is needed. Comparing profiles taken perpendicular to the beach last spring before placement, after placement, and again this spring, it shows material placed in 2020 is already eroding.
This demonstrates beach nourishment is critically needed at Minnesota Point and is providing a benefit to slowing erosion and protecting shoreline structures. This also is a strong indicator of the need for a Section 111 study under the Rivers and Harbors Act of 1962.
The City of Duluth requested, and the Corps of Engineers has initiated, a Section 111 study to develop long-term solutions to help mitigate for this high rate of erosion and maintain a healthy and natural shoreline. The Section 111 is in the beginning stages of the federal funding process. If authorized and funded, the Corps of Engineers will work collaboratively with the City of Duluth to ensure state-of-the-art methods are used to understand the science and establish recommendations for a way ahead.
For more information on Minnesota Point Beach cleanup, please contact Carrie Fox at firstname.lastname@example.org.