Log Salvage Efforts in Great Lakes Expanding

by Scott McEwen, Tip of the Mitt Watershed Council

One hundred years ago the rivers draining to the Great Lakes were choked with timber harvested from the surrounding lands. Many of the saw logs of the day became water logged or escaped and settled into the shallows of the Great Lakes. It is at the bottom that many of the logs have remained for close to a hundred years.

Today, there are efforts afoot across the Great Lakes to harvest these forgotten giants. For many there is great romance associated with harvesting these submerged logs, a glimpse into the by gone era of logging and lumber barons. For others there is the potential for profits from the logs whose valuable size and tight grain texture is no longer found in timber today. Today, the two motivations have combined into a growing industry of submerged log removal.

Although salvage log removal is nothing new, the State of Michigan in the summer of 2000 passed two laws that would facilitate permitting of log removal from the bottom of the Great Lakes. These laws are being administered through the Michigan Department of Environmental Quality Land and Water Management Division (LWMD). As part of the permit review process the LWMD is required to determine whether the log salvage operations will have any adverse environmental impact.

From an ecological perspective there is reason to proceed cautiously. Many Great Lakes fish utilize submerged logs either as cover or as feeding areas. Additionally, most of the proposed salvage operations are at the mouths of rivers, areas important to the transfer of nutrients between the open waters of the Lakes and their watersheds. River mouths are often important staging areas for self-sustaining runs of spawning Chinook salmon in the summer and fall followed by Steelhead in the winter and well into spring. Lake trout are also known to congregate in areas around river mouths.

Due to the ecological sensitivity of many of the log salvage areas, prior to permit approval for submerged log removal, it is important that a complete environmental assessment is conducted. At a minimum the Watershed Council suggests:

Project Location and Description

1. Provide a map with GPS latitude and longitude coordinates of the corners of the removal area.
2. On the site map show the GPS coordinates of the specific log location areas.
3. Provide a bathymetric map of the salvage site detailing the bottom depths and contours.

Currents

1. Describe the direction of the dominant currents, if any.
2. Describe how this activity, in association with the currents, may influence down drift habitat.
3. Show the location of any water surface water outlet in the vicinity.

On-site Habitat Assessment

1. Conduct a thorough sampling of the benthos of the area. This should include sampling on the logs and on any other surrounding substrate. Describe quantity and quality of benthic organisms.
2. Documentation of fish visitation to some of the log areas. This may be accomplished by establishing an in-situ video camera that records during scheduled time periods.
3. Describe the aquatic vegetation within the project area, including type, location, and abundance.
4. Describe the position of the logs on the bottom (whether they are crossed, in piles, or laying flat and singular). This can be accomplished by video documentation.
5. Describe any other habitat in the area (slab wood, rock, cobble, non-salvagable wood, etc.)
6. If dredging into the substrate is proposed a determination of the type of sediment below the surficial sand should be conducted. Describe the underlying substrate to the depth of the proposed dredging.

Off-site Habitat Assessment

1. Describe any other aquatic habitats in the area, particularly down drift, that may be affected by this activity.

Contaminated Sediments

1. Describe the process by which a determination was made that the area does not have contaminated sediments. This may include visual observation, contacts with the Environmental Response Division staff or through database and historical research.

Mitigation

1. Describe the habitat mitigation that is proposed. This should include the types of materials proposed, and the placement locations of the materials, and the configuration of the materials.

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