Consultant's Report - Minnesota State Legislature

Consultant's Report - Minnesota State Legislature Consultant's Report - Minnesota State Legislature

archive.leg.state.mn.us
from archive.leg.state.mn.us More from this publisher
29.07.2013 Views

MINNESOTA DEPARTMENT OF NATURAL RESOURCES Feasibility Study to Limit the Spread of Zebra Mussels from Ossawinnamakee Lake II. EXECUTIVE SUMMARY AND RECOMMENDATIONS STUDY OVERVIEW Ossawinnamakee Lake is a 644.0-acre (260.6 hectare) lake located in Crow Wing County, Minnesota. The lake has one outfall location that discharges into directly into Pelican Brook. The brook is a small stream that flows approximately 5.5 miles (8.85 kilometers) before entering into the Pine River. The Pine River is a tributary of the Mississippi River. In 2003, MN DNR documented the presence of zebra mussels (Dreissena polymorpha) in the lake. According the MN DNR Staff, the zebra mussel population in Ossawinnamakee Lake is a threat that needs to be promptly addressed. In response to the documented presence and threat of zebra mussel dispersal downstream, MN DNR requested a formal feasibility study of zebra mussel control technologies. The primary goal of the report was to provide an analysis of the effectiveness of potential technologies in preventing or limiting the in-water transport of zebra mussels, particularly the veliger stage, in the outlet stream of Ossawinnamakee Lake. The report reviewed existing and new technologies that may be effective in limiting not only the downstream dispersal of zebra mussel veligers but also the established population ofzebra mussels in Ossawinnamakee Lake. FINDINGS AND RECOMMENDATIONS, ' The study provided an overview of Ossawinnamakee Lake (Section III) and reviewed the historical, physical, and life history traits of the zebra mussel (Section IV). A review of known treatments along with their advantages and disadvantages was provided in Section V. An overview of the current Ossawinnamakee Lake copper sulfate treatments was also provided in Section V. Section VI of the report evaluated potential treatment technologies and provided a recommended set of objectives to be pursued. The technologies presented were objectively analyzed based on environmental and scientific/engineering points of view. The three major evaluation criteria included overall effectiveness, economics, and environmental impacts. A review ofthe technologies available for application to the Ossawinnamakee Lake zebra mussel population groups potential treatments into' five categories including biological, acoustic, chemical, electrical, and physical controls that have been utilized for zebra mussel control in either laboratory or I field applications. Although each treatment category has advantages and disadvantages, the evaluation revealed that a combination of treatments would yield a highly effective alternative that is environmentally friendly and targets all zebra mussel life stages. While chemicals are most widespread, other technologies are available that merit further consideration for planning, permitting design, and construction. These engineering solutions coupled with environmental operations and management solutions appear to have the most potential for success. This report recommends the following three objectives be considered for implementation: II-I Executive Summary and Recommendations

MINNESOTA DEPARTMENT OF NATURAL RESOURCES Feasibility Study to Limit the Spread ofZebra Mussels from Ossawinnamakee Lake Objective 1 - Continue Ossawinnamakee Lake and Pelican Brook veliger, and adult monitoring to detennine location and densities ofzebra mussels. Continue education and outreach programs to infOlID lake and brook users about the risk ofdownstream zebra mussel transport. Objective 2 - Implement dispersal control strategies that limit zebra mussel dispersal from Muskie Bay into Pelican Brook. A variety of solutions may be possible to limit dispersal downstream. In particular, the report reviewed a passive solution that incorporated a penneable barrier stretched from the lake bottom to the surface and from bank to ban1e The penneable barrier would allow water to pass through but would obstruct the movement of organisms from Muskie Bay into the area immediately downstream ofthe bay. Objective 3 - Implement population control strategies that target reduction or limiting the growth of the zebra mussel population in Ossawinnamakee Lake. Several proactive treatments could be utilized including the use of various chemicals that have known efficiencies for reducing the presence ofzebra mussels. ' Treated as just one system, the lake and brook together represent a wide variety of physical characteristics. For this reason, two general treatment locations were considered for the treatment alternatives evaluated: the lake itself and the brook. For lake treatment, the combination of Objective 2 and Objective 3 provide the most promising strategy for limiting downstream dispersal and reducing the size of the population. The lake location would serve as the primary treatment location that incorporated year-round treatment strategies. A second tier treatment location would be the brook. Several of the treatments reviewed could be applied to any populations that are discovered in the brook. Used in this manner, these treatments would represent a reactive response to the presence ofzebra mussels in the brook and would be applied on an as needed basis versus the proactive treatment ofthe population in the lake. IMPLEMENTATION Objective 1 is on-going and it is recommended that education, research and monitoring be continued and evett expanded. Implementation of Objective 1 could be coordinated through existing education, research and monitoring protocols established within MN DNR. It is recommended that appropriate funding be obtained to implement the planning, design, pennitting, and ultimately the installation of a penneable barrier outlined in Objective 2 and the associated proactive population treatments outlined in Objective 3. Based on the risk of the existing population, this system needs to be in-place within the next 12 months (prior to spawning downstream dispersal in 2006). To limit the risk of downstream dispersal between now and the implementation ofthe penneable barrier, the current copper sulfate treatments may be necessary to reduce the densities ofveligers in Ossawinnamakee Lake. 11-2 Executive Summary and Recommendations

MINNESOTA DEPARTMENT OF NATURAL RESOURCES<br />

Feasibility Study to Limit the Spread of Zebra Mussels from Ossawinnamakee Lake<br />

II. EXECUTIVE SUMMARY AND RECOMMENDATIONS<br />

STUDY OVERVIEW<br />

Ossawinnamakee Lake is a 644.0-acre (260.6 hectare) lake located in Crow Wing County,<br />

<strong>Minnesota</strong>. The lake has one outfall location that discharges into directly into Pelican Brook.<br />

The brook is a small stream that flows approximately 5.5 miles (8.85 kilometers) before entering<br />

into the Pine River. The Pine River is a tributary of the Mississippi River. In 2003, MN DNR<br />

documented the presence of zebra mussels (Dreissena polymorpha) in the lake. According the<br />

MN DNR Staff, the zebra mussel population in Ossawinnamakee Lake is a threat that needs to<br />

be promptly addressed. In response to the documented presence and threat of zebra mussel<br />

dispersal downstream, MN DNR requested a formal feasibility study of zebra mussel control<br />

technologies.<br />

The primary goal of the report was to provide an analysis of the effectiveness of potential<br />

technologies in preventing or limiting the in-water transport of zebra mussels, particularly the<br />

veliger stage, in the outlet stream of Ossawinnamakee Lake. The report reviewed existing and<br />

new technologies that may be effective in limiting not only the downstream dispersal of zebra<br />

mussel veligers but also the established population ofzebra mussels in Ossawinnamakee Lake.<br />

FINDINGS AND RECOMMENDATIONS, '<br />

The study provided an overview of Ossawinnamakee Lake (Section III) and reviewed the<br />

historical, physical, and life history traits of the zebra mussel (Section IV). A review of known<br />

treatments along with their advantages and disadvantages was provided in Section V. An<br />

overview of the current Ossawinnamakee Lake copper sulfate treatments was also provided in<br />

Section V. Section VI of the report evaluated potential treatment technologies and provided a<br />

recommended set of objectives to be pursued. The technologies presented were objectively<br />

analyzed based on environmental and scientific/engineering points of view. The three major<br />

evaluation criteria included overall effectiveness, economics, and environmental impacts.<br />

A review ofthe technologies available for application to the Ossawinnamakee Lake zebra mussel<br />

population groups potential treatments into' five categories including biological, acoustic,<br />

chemical, electrical, and physical controls that have been utilized for zebra mussel control in<br />

either laboratory or I field applications. Although each treatment category has advantages and<br />

disadvantages, the evaluation revealed that a combination of treatments would yield a highly<br />

effective alternative that is environmentally friendly and targets all zebra mussel life stages.<br />

While chemicals are most widespread, other technologies are available that merit further<br />

consideration for planning, permitting design, and construction. These engineering solutions<br />

coupled with environmental operations and management solutions appear to have the most<br />

potential for success. This report recommends the following three objectives be considered for<br />

implementation:<br />

II-I Executive Summary and Recommendations

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!