Lake Dredging

The removal of excess sediment from Easter Lake is a key component of the lake restoration plan. Since its creation in 1967, Easter Lake has lost 30% of its lake volume due to sedimentation. Excess sediment has accumulated in the lake bed overtime decreasing the lake’s volume, increasing phosphorus, and overall decreasing water quality.

The first phase of sediment removal within the lake began in 2016 with hydraulic dredging which removed 300,000 cubic yards of sediment. Since then, additional work has been completed through mechanical dredging processes and other projects. Mechanical dredging has removed an additional 250,000 cubic yards of sediment. Read more below to learn about the exciting progress we have made thus far.

October 2018

  • Throughout October seeding of shoreline will be finish and fish habitat work will be completed in preparation for remaining fisheries renovations work. Cedar trees placed for fish habitat will be wired up and tied down in the lake basin.

September 2018

  • In September, the trail bridge at Easter Lake was finished completing the Mark C. Ackelson trail around the lake. Beneath the bridge a silt dike was constructed to form a sediment basin on far west end of the lake to protect the main lake from filling in over time.
1

After completion of the pedestrian bridge, a silt dike was construction directly below the bridge.

August 2018

  • In August major progress was made in fish habitat installation along shorelines and in the lake bed. Jetties along the north shoreline were restored and armored with riprap. Additional shoreline work was completed.

July 2018

  • After years of sedimentation, the bay south of Easter Lake Drive was dredged out. The bay was deepened, and shoreline was extended to provide more parkland for recreational use. Shoreline was stabilized with Flexamat and fish habitat was strategically placed throughout this area. East of this bay, water from the incoming Magnolia Creek will be slowed down in wetland like areas before reaching Easter Lake. Fish habitat installation began throughout the lake at key locations in lake bed and along shoreline. Additionally, construction of the pedestrian bridge as part of the Mark C. Ackelson trail around Easter Lake began. Major work along Easter Lake beach was completed as shoreline was stabilized and deepened and fish habitat was installed including a fish spawning bed, catfish hides and cedar trees. By the end of July, nearly 20,000 feet of shoreline was stabilized, and 200,000 cubic yards of sediment was removed from Easter Lake.

June 2018

  • Throughout the month of June, sediment removal continued. Additional jetties were constructed throughout the lake and major progress on shoreline stabilization was made.

May 2018

  • During the month of May, sediment removal continued, with focus on the east arm of the lake. Three jetties were constructed in the east arm and the island in this part of the lake was removed and rebuilt to be much larger to provide fishing and recreational opportunities. Additionally, improvements to the boat ramp began. As part of these improvements, the bay was dredged out and the main arm of the bay was extended. Shoreline around the boat ramp and other shoreline areas was stabilized with a combination of grading, riprap and Flexamat.

February- April 2018

  • Throughout the spring, crews focused on removing sediment from the west arm of Easter Lake. With variable weather and lake bed conditions, crews continued to work throughout the lake where they could to remove sediment and begin construction of new jetties.

January 2018

  • At the start of the year, the lake bed was in such a condition that mechanical dredging work could begin. Over the course of 2017, the lake bed needed to dry out to become stable enough for heavy equipment and hauling trucks to maneuver throughout the lake. In January, construction crews began removing sediment from the west arm of the lake.
DSCN5901

January 2018 – Start of mechanical dredging, west arm of the lake. The pedestrian bridge is now located just to the right of the machinery pictured here in January.

Fall 2017

  • Throughout 2017 and into the fall, project partners worked with engineers to identify and develop a comprehensive plan to remove additional sediment from Easter Lake, restore shoreline, install fish habitat, and complete the Mark C. Ackelson Trail around Easter Lake. In late Fall, a contractor was hired to complete in-lake work. In late December of 2018 a preconstruction meeting was held.

May-June 2017

  • As part of watershed improvements, construction began in May of 2017 for a stormwater wetland and sediment basin on the northeast side of Easter Lake. To construct berms for the wetland and future sections of the Mark C. Ackelson Trail around Easter Lake, fill dirt from the lake was used. Construction of this wetland was finished in late June of 2017. Today the stormwater wetland helps to treat and slowdown 37 acres of stormwater runoff of an adjacent neighborhood before entering Easter Lake. In total, this wetland helps to reduce 9.1 millions gallons of stormwater each year and reduces 70 lbs. of nitrogen and 20 lbs. of phosphorus loading each year. Improvements like this wetland will reduce sediment and pollutant loading into Easter Lake, protecting the lake for years to come. To learn more about this project click here.

May 2017

  • In May of 2017, dredging of 4,000 cubic yards of sediment was completed in a bay near shelter 4 at Easter Lake Park. Sediment was removed mechanically and deposited in a nearby location within Easter Lake Park. Dredging of this bay was targeted to provide greater fishing opportunity and accessibility to park users. In the future, fish habitat will be installed, and the railing of the deck located at shelter 4 will be adjusted to allow for handicapped fishing opportunities.

Winter 2016-2017

  • In late 2016, the gate was partially opened to start the drawn down of Easter Lake. Initially the gate was partially opened to give fish a chance to move down stream. In early 2017, the gate was completely opened to finish draining Easter Lake in preparation for shoreline and habitat work.

May – December 2016

  • Throughout the latter half of 2016, hydraulic dredging removed approximately 300,000 cubic yards of sediment from Easter Lake. This sediment was pumped through a pipe across the Des Moines River into a gravel pit now officially named the Vandalia Wildlife Refuge which was acquired by Polk County Conservation in 2014.

April 2016

  • In mid-April a hydraulic dredge was moved onto Easter Lake. A hydraulic dredge floats on the water excavating and pumping material through a temporary pipeline to an offsite location. The dredge acts like a floating vacuum cleaner that can remove sediment very precisely. It is an unobtrusive method that does not disturb the shoreline and only requires one trip to put the dredge in the water and one trip out when work is complete. The sediment that is hydraulically removed from Easter Lake was pumped through a pipe, across the Des Moines River into a newly acquired gravel pit owned by Polk County Conservation now known as the Vandalia Wildlife Refuge.
20160413_112928

Preparing for the dredge to moved onto Easter Lake, April 2016

Historical Lake Management

  • Since its creation in 1967, Easter Lake has endured a series of management strategies to restore lake health and improve the fishery. Despite these management strategies, water quality continued to decrease. Below lists some of the key management strategies that have taken place.
    • 1971 First sport fish including channel catfish were stocked in the lake
    • 1974 Original jetties and boat ramp are constructed
    • 1974 Chemical treatment to control undesirable fish species
    • 1975 Shoreline control measures implemented
    • 1978 Chemical treatment to control undesirable fish species
    • 1981 Walleye stocking begins
    • 1981 Water draw down by 11 feet
    • 1989 Grass carp introduced for aquatic weed control
    • 1990 Water sampling
    • 1997 Retention pond construction
    • 2000 Pollution prevention plan for the Des Moines Airport Implemented
    • 2001 Sediment Pond construction
    • 2002 Fisheries restoration
    • 2005 Sediment pond construction
    • 2013 Start of the Easter Lake Watershed Project

To learn more about lake renovations and improvements click the links below:

Advertisements