Edgewater Resources' Report Reveals No New Solutions For Dealing With Kazoo Harbor Sedimentation Issues
The Edgewater Resources’ draft report about the September 15 meeting that gathered Douglas and Saugatuck city officials with Michigan regulatory agencies at the state capitol in Lansing over Kalamazoo Harbor sedimentation issues does not contain anything new that hasn’t already been said in some fashion or other by officials.
Still, Douglas City Council woman Lisa Greenwood, also treasurer of the Kalamazoo Lake Harbor Authority, recently noted, “It very concisely reflects the road we have been going on so far.”
The engineering firm, which the cities engaged to conduct a master plan with the aim of creating a viable, long-term solution for the harbor, distributed the report to Saugatuck and Douglas early last month.
“The second step (following the September meeting with agencies) is a face-to-face meeting that will occur here in the community—it will bring those state representatives here,” Douglas City Manager Bill LeFevere recently said.
The report identifies four approaches the community can take, with the option of combining some: ‘doing nothing;’ continuing with the same approach of dredging when necessary; construction of sediment traps; and construction of structures to channelize the flow of the Kalamazoo River to Lake Michigan.
“Regardless of the approach selected, a sediment management plan should be created as a long-term strategy for overall sediment reduction,” states the document
“Regional sedimentation issues, specifically sediment loading from agricultural and urban sediment runoff, should be the focus of the sediment management plan,” it goes on to state, adding the issue will require a cooperative effort with local and regional communities.
“The Rabbit River watershed is the first upstream watershed leading to the local harbor and contributes a significant amount of sediment into the Kalamazoo River watershed system,” the report continues.
Directly citing from the Rabbit River EPA Watershed Assessment of River Stability and Sediment Supply (WARSSS), published in 2008, the report offers the recommendation to “encourage environmentally sensitive agricultural practices to reduce the potential for surface erosion and sediment delivery to streams, including conservation tillage and implementation of filter strips/riparian buffers.”
Of the ‘do nothing approach,” the document says, in part, “the current rate of sedimentation into Kalamazoo Lake is approximately 36,000 cubic yards per year.
“If this rate continues without control or dredging, it will eventually lead to the transformation of Kalamazoo Lake into a marshy area with a narrow meandering river channel.”
Of continuing with the current approach, the document states, “Costs to complete the dredging were estimated to be well over two million dollars and funding for the work was not identified. This approach is reactive strategy that is not financially viable for local government and riparian owners over the long-term, without a proactive funding mechanism.”
With regards to sediment traps, the report indicates they “would be designed to intercept and capture sediment at strategic locations intended to minimize downstream deposition, to separate clean material if possible, and to facilitate straightforward maintenance dredging.”
It goes on, “The success rate of a sediment trap is difficult to determine without a detailed study of the flow conditions and sediment transport within the region.”
Of channelization, the document states: “Channelization of the river is intended to keep the sediments moving through Kalamazoo Lake and eventually into Lake Michigan.”
While beneficial, channelization has many obstacles, according to the report.
“Initial feedback during the September 15, 2015 agency meeting indicated that the USACE (U.S. Army Corps of Engineers and MDEQ (Michigan Department of Environmental Quality) might contest the idea of moving contaminated sediment into the navigation channel downstream of Kalamazoo Lake.
“In addition, while the USACE was not represented at the meeting, channelization would likely result in an increased dredging burden on the agency and therefore, would likely result in opposition.”
Elsewhere, the report notes another problem.
“Lastly, after channelization is complete, the communities and riparian owners will still be left to determine how to maintain navigation from the shoreline to the high-flow channel, likely by additional dredging.”
The full report is available at either Saugatuck or Douglas city halls.