News and information for the worldwide dredging industry

Bookmark and Share Email this page Email Print this page Print

Great Lakes Remediation Group Completes Key Wildlife Restoration on Harsens Island

Brennan’s amphibious equipment included a CAT 324E excavator mounted on amphibious
tracks loading into amphibious dump trucks, to create a four to five foot deep channel with 1:10 side slopes along three miles of Krispin Drain.performed all tasks necessary to perform the project, which returned Krispin Drain to a free-flowing wildlife habitat and kayaking waterway.

Brennan’s amphibious equipment included a CAT 324E excavator mounted on amphibious tracks loading into amphibious dump trucks, to create a four to five foot deep channel with 1:10 side slopes along three miles of Krispin Drain.performed all tasks necessary to perform the project, which returned Krispin Drain to a free-flowing wildlife habitat and kayaking waterway.

Great Lakes Sediment Remediation, LLC (GLSR) has completed the Krispin Drain Habitat Restoration, moving the State of Michigan one step closer to eliminating a major environmental area of concern (AOC).

Within the AOC are Beneficial Use Impairments (BUIs), all of which must be addressed before the Area of Concern can be removed from EPA’s list. The Drain was one of 10 Fish and Wildlife Habitat Impairments (BUIs) within the AOC.

The project award was just more than $3.5 million.

Krispin Drain is an artificial waterway that traverses the center of Harsens Island, which is part of the St. Clair River Great Lakes Area of Concern (AOC).

Harsens Island is in the delta of the 40-milelong St. Clair River, which flows in a southerly direction from Lake Huron to Lake St. Clair and forms part of the international boundary between Michigan in the U.S. and the province of Ontario in Canada. The river branches into several channels at its mouth in the north end of Lake St. Clair, forming several islands, one of these being the 10-square-mile Harsens Island. The island constitutes a third of Clay Township.

The four-mile-long waterway had become overrun with the invasive reed Phragmites australis and clogged with silt since its last maintenance in the 1960s.

Brennan’s amphibious equipment excavated along three miles of the Drain, transferring material onto on-road dump trucks at four staging areas. GLSR’s three partners performed all tasks necessary to perform the project, which returned Krispin Drain to a free-flowing wildlife habitat and kayaking waterway.

The project to restore the lost habitat involved removing 26,000 cubic yards of material from the three upper miles of the Drain. The remaining lower stretch, which runs through a wildlife refuge and waterfowl hunting area, is managed by Michigan Department of Natural Resources and was restored by that agency. The Drain empties into Little Muscamoot Bay in Lake St. Clair.

General contractor GLSR is a joint venture including J.F. Brennan Company, Environmental Restoration, LLC (ER), and Natural Resource Technologies (NRT). Brennan performed the dredging and other waterside operations, while ER handled the upland operations. Engineering firm NRT provided technical assistance on the project.

ER’s excavator loads a dump truck at one of the staging areas, which was created by stripping the topsoil, and laying non-woven geotextile covered with gravel. The stockpile was created by the amphibious dump trucks self-dumping on the crane pad.

The contracting agency was the Environmental Protection Agency’s Great Lakes National Program office (EPA GLNPO), with Rose Ellison serving as EPA’s project manager.

Brennan mobilized low ground pressure tracked vehicles to accomplish the dredging and transporting. The excavators are CAT 324E machines mounted on flotation tracks. They have a two-cubic-yard capacity with a short stick, and about 1.5-cubic-yard capacity with a 55-foot stick. The excavators loaded tracked amphibious dump trucks that were especially designed and built for Brennan. They can fully float with a payload of 40,000 pounds. Brennan owns three of the dump trucks, which are 38 feet long by 26 feet wide, standing about 13 feet high. Each one can be trucked in three loads and assembled in a few hours. The trucks function like conventional dump trucks, with latching tailgates and the ability to self dump.

“The machines are capable of full flotation, but of course have limited operation in that mode. They have a very low PSI rating even when fully loaded – 1.2 to 1.8 PSI – so they can work in very fluid conditions, as was the case at Krispin Drain. The trucks will touch bottom in about five feet of water, and as long as they can find footing, they can travel with ease,” explained Victor Buhr, vice president of Brennan’s Environmental Group.

On-road dump trucks place material at Horvath Disposal Cell, one of two placement areas designated to receive material from Krispins Drain on the island.

The amphibious excavator dug and shaped the channel with the aid of RTK GPS and inclinometers interfaced with Hypack’s Dredgepack ® suite on the operator’s computer, displaying the bucket position in real time with relation to the channel design template.

Specifications called for dredging the drain and grading the banks to the appropriate stable angles by removing existing piles, grading 10:1 slopes on the outer third of the drain channel, and shaping a four- to five-foot-deep thalweg in the middle third of the channel. Part of the project is to plant native riparian vegetation in the adjacent drain easement.

“We started at the beginning of September and ended in mid-December,” Buhr said. “Due to the wet conditions in the disposal areas, there will be some grading and seeding work left in the spring,” he said.

There were two substrate restorations to be performed following the excavation. Brennan used its amphibious equipment to place the substrate material, which consisted of four- to eight-inch round rock in an approximately onefoot-thick layer above the excavated elevation, explained Brennan project manager Tyler Lee.

The dump trucks transported the material to four dredged material transfer sites along the drain, where they emptied their loads onto a stockpile next to the staging area. A standard tracked excavator owned and operated by ER worked on crane mats on top of the very soft soil, loading sediment from the stockpile into on-road dump trucks, which transported the material to one of two permanent placement sites on the island. Transport distance between the drain and the placement sites was a maximum of two miles.

The transfer sites were spread out along the drain to keep the haul distance of the amphibious equipment under one mile, increasing the overall production, Lee said. He explained that the sites were built using a dozer to strip topsoil, followed by the installation of a non-woven geotextile on the exposed ground, with a layer of gravel placed on top of the geotextile, providing stable ground for the on-road dump trucks to navigate.

The channel depth was uniform throughout the project, but the overall width of the drain varied from about 30 feet to 100 feet, Lee said. The two disposal cells were created by using a dozer to strip the topsoil from the stockpile area and using the topsoil to create a containment berm around the cell. After delivery to the cell by the on-road dump trucks, the material was windrowed by a dozer and worked until dry enough to be placed in layers within the cell. Ground corn cob was used to aid in drying the material.

The goal of the project as defined by EPA was to re-establish hydraulic flow in the drain and to maintain the habitat for fish,  macroinvertebrate, herpetofauna and avian populations. Prior to the start of dredging, the first step was to kill off the Phragmites with a herbicide. When the dredging began, Brennan separated the dead stalks and roots and shipped them to a landfill.

With the completion of the project, a twoyear monitoring period begins, to ensure that the goals of the project – the absence of Phragmites, continued water flow and viable wildlife habitat – continue to be met.

“We are fortunate to have an institutional partner in the St. Clair County Drain Commission, who will take over maintenance of the Drain after the two year monitoring period,” said Rosanne Ellison, EPA project manager.

“The river has come a long way since the 70s”, Ellison said, “a lot of work has been done.”

PROJECT BACKGROUND

Krispin Drain was originally excavated in the 1940s and named for Dan Krispin, who did the original digging, said Artie Bryson, Clay Township supervisor. The project is a win-win for the citizens, he said. As an EPA-funded project, the cost is not assessed to the citizens of the township, of which a third is Harsens Island and 2/3 is across the river in the vicinity of Algonac, Michigan. A privately run car ferry provides access to the island across the river channel.

With its restored flow and wildlife habitat, Krispin Drain will be designated as part of the “Blueways of St. Clair” National Water Trail for kayakers.

In 1985, the U.S. and Canadian governments identified the St. Clair River as one of 43 Areas of Concern (AOCs) in the Great Lakes. In 1992, the St. Clair River Bi-national Public Advisory Council (BPAC) developed a Stage I Remedial Action Plan (RAP), which described the environmental problems in the St. Clair River, and identified the beneficial use impairments (BUIs) and their causes. The causes of the Loss of Fish and Wildlife Habitat impairment were defined as significant loss of wetlands, and extensive bulkheading and infilling of the shoreline. These alterations have occurred along much of the river, on both the U.S. and Canadian shorelines, and eliminated or altered the shallow water areas that provide spawning, rearing and feeding sites for many species.

In 2008, the Michigan Department of Environmental Quality (MDEQ) revised its Guidance for Delisting Michigan’s Areas of Concern, providing the criteria to be met for removal of each impairment (BUI) within an Area of Concern. To address Loss of Fish and Wildlife Habitat, the guidance requires that a restoration plan be developed and implemented.

The revised 2013 St. Clair AOC Fish and Wildlife plan identifies 10 locations where restoration is required to remove the impairments. Krispin Drain is the last of the 10 locations on the Fish and Wildlife Habitat BUI. Four sites under other BUI designations – restrictions on fish and wildlife consumption, bird or animal deformities, restrictions on drinking water consumption and beach closings -- remain, and will be addressed in the coming year, EPA’s Rose Ellison said.

Add your comment:
Edit Module