WWMD PROPOSED OVERWINTER DRAWDOWN PUBLIC INFORMATIONAL MEETING JULY 12, 2016 PRESENTED BY: Mark Kordus - Lake Services Manager Mark@WisconsinLPR.com (715) 781-9976
WHY IS IT BEING CONSIDERED AS AN OPTION? • Mimics natural/seasonal variation of water levels which are now artificially controlled by a dam • Can offer some sediment compaction, particularly in areas of soft sediments • Can be an effective non-chemical mechanism to control the invasive plant Eurasian water-milfoil (EWM) • Very low cost and permit is valid for 5 years • Can reduce nuisance aquatic plant growth for 2 growing seasons post drawdown • Can be effective at reestablishing main channel areas and increasing depths, enhancing navigational opportunities • Can offer greater native plant diversity post drawdown by stimulating growth of dormant seed banks
WHAT ARE THE POTENTIAL DISADVANTAGES? • Loss of some uses of the waterway from October – April; in particular, fall waterfowl hunting. Ice fishing on Tichigan Lake proper would likely not be significantly impacted • Open water access during the time of drawdown would likely be limited to smaller craft • Aesthetically not visually appealing to look at • Possible fish kill • Potential odor from drying sediment or dying plant material • Reliant on mother nature and a cold winter for maximum effect • Can affect northern pike spring spawning, depending on spring and refill schedule
TIMELINES AND LOGISTICS • The drawdown will start on or about Monday Sept. 19 (or 26 th ) at a rate of about 4” per day to a maximum of 5’ as measured at the head of the dam • This rate would allow fish and other aquatic organisms to safely migrate to deeper water • The system would reach full drawdown approximately 15 days after it begins, assuming no major storm events; which would be Oct. 5 (or Oct. 12) • Refill would depend on how early of an ice-out/spring we have, but would occur at the same rate of 4” per day and would be fully refilled by no later than the weekend prior to the first Saturday in May • Doesn't need to occur in 2016. It could be completed in 2017 or later as permit is valid for 5 years • Will NOT be completed in consecutive years (i.e. winter of 2016/17 and 2017/18)
WHAT WILL IT LOOK LIKE? (PICTURES FROM 2011)
COMMON CONCERNS WE HAVE HEARD “ All the fish will die or be trapped” • As the water level drops and water drains from Tichigan Lake proper, the channel between the Lake and Fox River will be monitored to ensure adequate depth for fish and other aquatic organisms to be able to pass between them. Actual final drawdown depth will be based on maintaining this interconnection. • The slow rate of drawdown (4” per day) will allow for fish and other organisms to migrate safely to deeper water • The bathymetry (depth contour) mapping doesn’t show any backwater areas remaining during full drawdown, which indicates potential for trapping of fish. It doesn't appear this was a problem for the emergency drawdown done in 2011 at a greater rate than is proposed here
COMMON CONCERNS WE HAVE HEARD “ It will affect the river all the way to Waukesha” • The approximate affect will reach from the dam upstream to areas of equal water elevation, or approximately to the Racine/Waukesha County line. Elevation of water at the dam is 776 ft and is approximately 776 at the County line (FEMA, 2012 data)
COMMON CONCERNS WE HAVE HEARD “ The 2011 drawdown negatively affected water clarity and this will too” • Water clarity varies annually based on many factors, but heavily influenced by precipitation and runoff • Water clarity has been sampled on the waterway dating back to 1988 with 312 total recordings • Average clarity before 2011 was 5.6 ft • Average clarity after 2011 is 6.2 ft
COMMON CONCERNS WE HAVE HEARD “Its going to smell!” • Yes there will be some odor when the reservoir is drawn down from decaying plant material, as well as potentially exposed organic sediment. • This will be minimized to the greatest extent possible by timing the drawdown as late in the fall as possible. Plants will be naturally dying back already at this time of the year, days are not as hot, and after the initial frost both possible issues should become less of a concern.
COMMON CONCERNS WE HAVE HEARD “Driven point wells will dry up” • NR 812 “well casing pipe–not including the screen–must extend to at least the 25-foot depth or to at least 10 feet below the static water level, whichever is the greater depth” • If the well is constructed as per code requirements it is very unlikely it would be affected by a drawdown of 5’ • Ground water typically contributes to surface water, not vice versa • In 2 of the recent permanent dam removals in Wisconsin; Campbellsport dam (Milwaukee River) and Merrill Ward Paper dam (Prairie River), there were no reported instances of wells drying up or having problems during or after dam removal
COMMON CONCERNS WE HAVE HEARD “All the animals who rely on the adjacent wetlands are going to die because they don’t have any water” • The dam and impoundment itself are not natural they are man made. Plants, animals and reptiles will survive as they have for the past thousand plus years prior to the relatively “new” dam being installed • The wetlands contribute to the waterway and will likely continue to do so even during the drawdown and may be even more visible when fully drawn down • Nearshore wetland plant comminutes typically flourish post drawdown, further enhancing the entire ecosystem
COMMON CONCERNS WE HAVE HEARD “What is our (District) liability?” • This is a legal and/or insurance question • As part of the permitting process, notices will be provided to those individuals likely to be impacted by the extent of the drawdown and public hearings will be held for all members of the public to participate and comment • The liability possibly may not be any different than the drawdown that was performed in 2011 or for any other project the District is considering; dredging, aeration, etc • The permit, if issued by WDNR, will likely have numerous and very specific conditions to protect the public interest
COMMON CONCERNS WE HAVE HEARD “All of the sediment will be washed downstream” • The water levels will be dropped at a slow and controlled rate of 4” per day or less, which is less than the 2011 drawdown, and refilled at similar rate • There may be small amounts of sediment transported downstream during storm events. Ultimately this is one of two functions of a river, which acts as a hydraulic conveyor that transports both water and sediment. This is one reason why reservoirs “age” more quickly than natural lakes as they accumulate sediment that was meant to passed through by the river system but instead is blocked and allowed to settle within the impoundment.
COMMON CONCERNS WE HAVE HEARD “This is a money making proposition for the consultant and the District” • Wisconsin Lake & Pond Resource will very likely experience a substantial reduction in the amount of fee-based work performed for the District post-drawdown, based on other similar projects • The District has no direct financial benefit (income). Rather, there is the potential for reduced expenditures on harvesting and/or herbicide treatment. This would not be any type of income per se, but instead a reduction in capital annual expenditures
COMMON CONCERNS WE HAVE HEARD “What will the WDNR allow us to do along our shoreline or in the lake bed adjacent to our property when the reservoir is drawn down?” and “Will there be the ability for bulk permits to be issued by the Department at central location to make it easier for riparian owners?” • This question will be answered at the meeting by WDNR staff who are present
THANK YOU FOR ATTENDING A public opinion survey on the drawdown is still available until July 27 online at: www.surveymonkey.com/r/waterford-waterway-drawdown Also available via link on WWMD’s webpage : www.waterfordwwmd.com
Recommend
More recommend
