Lakes Drawdown Updates
Lakes Drawdown and Dredging Project from DNR
- The Lakes Drawdown and Dredge Project that began on July 8,2019 with the drawing down of the lakes has been extended another year. After the first season of the drawdown Cravath Lake has been fully drawn down. Trippe Lake will need another season of drawing down to get to the lowest level possible.
- To help with the drawdown of Trippe Lake, siphons were added over the spillway this past summer. Additional siphons will be added in spring of 2021. This will increase the flow out of the lake allowing the lake to continue drawing down over the next year.
- The dredging phase of the project is scheduled to take place the winter of 2021/2022. Both lakes will be drawn down through this entire process and would be refilled in the spring of 2022. The hope is to improve water quality and depth, reduce aquatic vegetation and eliminate certain invasive aquatic plant species. Please follow our website www.whitewater-wi.gov for more information as this exciting project begins.
Current Status of Lakes
- Cravath Lake drawdown completed this past fall
- Trippe Lake drawdown to continue through 2021
Drawdown Project Continues
- Completed the removal of the rock ledge in Cravath Lake. (May 2020)
- Siphon project for Trippe lake to continue drawdown. (July 27, 2020)
- Planning for potential dredging for winter of 2021/2022 (Project bid scheduled for late October 2020)
- Lakes remain drawdown in 2021
- Apply for all needed permits winter of 2021
- Apply for a lake restoration grant in February 2022
- Potential bidding for dredging
- Dredging (mechanical) potentially in the Winter of 2021-22
- Potential controlled burn for emergent vegetation in the fall of 2021 or spring of 2022
- Refill early to late spring of 2022
Shoreline Erosion Control Types
- Riprap- WI DNR permit may not be required for proposed rock riprap shoreline erosion control projects. This includes the placement of new rock riprap, and also the repair and replacement of existing rock riprap.
- Biological Shore Erosion Control Structures- Examples include structures that are made up of biological materials; native grasses, trees, live stakes and posts, non -treated wood, mats, fiber rolls, etc.
Dredging Permit Guidelines
- No Permit required for less than 2 cubic yards total per year (about one small dump truck full)
2 TYPE OF PERMITS REQUIRED FOR LARGER PROJECTS
- General Permit- Small Scale Dredging (not exceeding 25 cubic yards)
- Individual Permit- Lake or Stream Dredging Individual Permit Checklist (exceeds 25 cubic yards or does not meet other checklist requirements)
Timeline and Cost for Permits
- General Permits- Have a 30-day turnaround and cost $303
- Individual Permits- Have a turnaround time of 45 to 90 days and cost $603
Resident Shoreline Projects Timeline
- The City will be performing their dredging project over the winter of 2022. Residents who choose to do their own shoreline restoration and dredging projects will want to complete them by June 10, 2022.
- The City is scheduled to begin refilling both lakes starting June 14, 2022. The lakes will slowly refill depending on precipitation levels.
Drawdown Time frame
Summer of 2019- Spring 2021
- Drawdown of Cravath and Trippe Lakes July 8 – September 30, 2019
- Dredging project anticipated to begin winter of 2020/21
- Lakes remain drawn down through out this time frame
- Lakes to be refilled in the spring of 2021
Approximate Dredging Volume and Cost
Potential Dredging Plan
- Cravath Lake = 37,000 cubic yards
- (Would provide a 50’ wide channel at 5 ‘ depth side slopes of 10:1)
- Trippe Lake = 44,000 cubic yards
- (Would provide a 50’ wide channel at 6 ‘ depth side slopes of 10:1 )
Total Material Removed Approximately = 81,000 cubic yards
- Subtotal = $1,063,055.20
- Contingency (20%) = $ 212,611.04
- Total Construction Costs = $ 1,275,666.24
Proposed Dredging Area and Current Status of Lakes
Cravath Lakefront Lake Drawdown and Dam Repairs Update August 1, 2019
Cravath Lake Drawdown Update July 26, 2019. Trippe Lake planned to start in early August.
Week of July 8, 2019
City Manager, Cameron Clapper and Parks & Recreation Director Eric Boettcher worked with city staff David Himsel and Andy Ascher to open the dam at Cravath Lake allowing water to flow both under and over it. Monday, July 8th was the first day to release water from the lake. A marker was painted on a nearby rock in order to monitor the amount of water dropping each day. Cameron released more water Wednesday, July 10th. There is a drain located in the Mill pond near the 5 American Flags Memorial. The water will drain here and at the bottom of the dam allowing additional water to flow under Main street toward the creek. This is the first step of the drawdown. Staff will monitor the amount of water that is removed from Cravath lake and make alterations as needed to stay on track. Stay tuned for more updates as the drawdown progresses.
- What is a lake drawdown?
- Why would the City of Whitewater do a lake drawdown?
- When will the drawdown begin and how fast will it go down?
- Is there concern about how long it will take to fill back up?
- What will happen to the fish and other wildlife in the lake?
- What are our personal dredging options during the drawdown? Are there any exemptions? Can I remove any material without a permit?
- Is there a list of contractors providing shoreline work?
- Can we remove trash from the exposed bed? Can we remove material such as broken glass?
- Can we use this opportunity to add pea gravel?
- Can we remove large boulders/rocks?
- Can I replace or repair my rip rap?
- Can I put in new rip rap? If not, what are other options other than rip rap for shore stabilization? What if I need rip rap to protect from man-made waves (boat traffic)?
- Will the starry stonewort be sent downstream during the drawdown?
- Will I be able to walk on the lake bottom?
- Will the boat launches be open this Fall, Winter, Spring?
- Can I remove the plants from the bottom of the lake in front of my house?
- What plants or algae will die during the freeze and which will come back next spring/summer?
- This year there was all this green stuff floating on the water over the past few weeks, what is that and will it go away next year?
- I’m losing 2 seasons of my lake use; will this really work?