Laserfiche WebLink
<br />Item 5.2. <br /> <br />MEMORANDUM <br /> <br />TO: Mayor and City Council <br /> <br />FROM: Rebecca Haug, Environmental Technician <br /> <br />DATE: October 4, 2004 <br /> <br />SUBJECT: Consider Curlyleaf Pond Weed Remediation in Lake Orono <br /> <br />On October 20, 2003, the Elk River City Council approved a drawdown of Lake Orono <br />to help eradicate curlyleaf pond weed which had proliferated in the lake. This is a non- <br />native invasive species that can clog shallow areas of waterways if not controlled. <br /> <br />According to Wendy Crowell, Aquatic Biologist, Exotic Species Program, Department <br />of Natural Resources (DNR), the drawdown did reduce the abundance of the curly leaf <br />pondweed; however, temperatures were not as cooperative causing several curly leaf <br />pondweed plants to survive the drawdown. At the August 18, 2004 Lake Orono Water <br />Quality Task Force Meeting, it was discussed that another drawdown could reduce the <br />abundance even more. City Staff has discussed this with DNR Waters, Fisheries and <br />Aquatic Plant representatives and none of them had concerns with another drawdown. <br /> <br />The drawdown would be done the same way it was last year. It is proposed to start on <br />November I, 2004 with a gradual four-foot drawdown of the lake (approximately over a <br />one-week period), allowing the lake sediment to dry (approximately one week <br />depending on weather) and having cold temperatures to freeze the plant bulbs that are <br />contained in the sediment of the lake (approximately ten days). The lake will then be <br />refilled gradually (approximately over a one-week period). If temperatures are <br />cooperative, the drawdown is proposed to only last one month. DNR Fisheries will <br />determine if the lake needs to be refilled sooner if there is a threat of a fish-kill. <br /> <br />The public will be notified of the drawdown through the City's website, The Current, the <br />Elk River Star News and the Lake Orono Improvement Association flyer sent to all lake <br />shore owners. Anyone wishing work along their shoreline other than general cleanup, <br />will need to contact the Building and Environmental Department to make sure their <br />project conforms with shore land regulations. <br /> <br />Staff has discussed this with both Elk River Municipal Utilities and the Street <br />Department. The cost for this remediation is $0. <br />