Tour of the Yahara River, June 2002

On June 25, 2002, members of the Dane County Lakes and Watershed Commission, the Yahara Lakes Advisory Group and others took a tour down the Yahara River to see first hand factors affecting lake levels. Following are some participants' observations.

Members of the flotilla included Dane County Lakes and Watershed Commission members, Yahara Lakes Advisory Group members and other concerned individuals.

Stan Nichols, UWEX

• Lakes Mendota, Monona, Waubesa and Kegonsa used to be part of one large Glacial Lake Yahara, and water levels have been dropping for 10,000 years since then.
• Dyreson area is illustrative of fact that Indian remnants are usually found within ¼ mile of water.
• We've lost 1/3 of the aquatic plant species from the Yahara Lakes in the last 100 years, and that's significant if we think of the lakes as a natural area.
• Big problem: invasion of exotics such ascurly-leaf pondweed and Eurasian water milfoil. Hydrilla has good potential of being the next exotic aquatic plant invader, and it grows quickly, but with the strong interest in water gardening and back-yard ponds there is a plethora of potential that we aren't even thinking about that can be ordered through catalogs. A problem with hydrilla is that it looks very similar to the native waterweed (Elodea canadensis) so it could invade without being easily detected.
• Plants in the river (Mud plant, wild celery, pond weed) are adapted to floating water environments - they flow with the current.
• We observed an increase in water clarity below Lower Mud Lake, and that indicates that plants in Lower Mud are filtering water

John Dunn (Dane County Public Works)

• Staff gauges he pointed out during the paddle and the acoustic velocity meters (add specific locations here) allow measurements that are important for making wise decisions.
• The trip just taken suggests there's value in having trained docents available to interpret this and other trips - floating classrooms.
• Stan Nichols and Dick Lathrop (DNR Research) - on practice of mechanical harvesters offloading plant piles along the river.
• Plant loads are mostly water. Some nutrient leaks back to the water from plants as they decay, but the nutrient content is low. (Dick's comparison of P in plants v. P in water column)
• Advantage of many piles versus larger pile along the river? This is mostly an aesthetic issue.
• Machine operators should be trained not only how to operate machines, but also when and where to cut plants.
• Until study shows that plants are major constrictions on flow, more ecological damage is done than benefits of cutting

Peter Hughes (US Geological Survey)

• The only change in the channel seasonally is plant growth, and it does have a backwater effect.

Ray Potempa (Friends of Lake Kegonsa Society)

• Any lowering of water levels in Kegonsa to increase head and increase system flow will have an effect on riparians. On the east side of Kegonsa piers are already 100 feet long to reach any depth for launching.

Look carefully to see evidence of a former bridge below the water's surface near the Dyreson Road bridge. It has cultural historical significance because the bridge was built in the late 1800s.

Larry Nelson (City of Madison Engineering)

• Lake level orders haven't changed for years, but operation has changed over the last 15 years. The summer maximum is now treated as the minimum for Lake Mendota
• City of Madison houses were generally built on higher land and generally do not experience flood damage. The city does have problems with sanitary and storm water. City of Monona homes have greater problems when built in low areas.
• Lake levels have been rising, and no one is taking responsibility for action. Not sure if it is practical to have upstream development alone incorporate new practices to infiltrate water.
• Surprised at how little data we have on quantity issues on these lakes.

John Magnuson (Prof. Emeritus, Center for Limnology; Lakes and Watershed Commission)

• Two things suggest worsening trends: first is higher percentage of imperviousness which is generating runoff. Older developments were not built for infiltrating water.
• Second is over the last 60-80 years we've seen a higher percentage of rain in extreme events. This leads to increased soil saturation and more runoff.
• Need to pay more attention to trapping water at the source.

Ken Potter (Prof. Civil and Environmental Engineering)

• Optimistic that can trap more water at the source and prevent more flooding
• Demonstrations are needed on different approaches
• Retrofits are harder due to land scarcity, but people are doing things regardless
• Already have flooding problems and need to look at all possible approaches to preventing future problems - and looking at the "plumbing" of the Yahara River

Brett Hulsey (Sierra Club, Lakes and Watershed Commission)

• Sierra Club has submitted grant application to McKnight Foundation for Don Hey to look at Yahara system
• Farm bill provides opportunities to get money for directing development in the northern part of the basin, preserving farmland, and implementing purchase of development rights strategies.

Shary Bisgard (Lakes and Watershed Commission)

asked for input on Commission direction on these issues. The following suggestions and observations were offered on next steps:

• Increase funding for studies and monitoring. County spends very little money on monitoring and it's been a fight during budget process for the last 12 years to maintain monitoring support (Lathrop)
• Commission has supported keeping monitoring in the budget. This is not a flashy item, and it's helpful to have outside interests come and testify; contribute to budget hearings and position/advocacy papers (Karen Cornwell and John Van Dinter)
• Commission should take lead in looking at info needs and other YLAG recommendations, put together a comprehensive package (not just individual gage requests) of budget needs for monitoring, modeling, and study, and advance this through the process (several)
• County budget is not only place to advocate. Proposal should be prepared to Sen. Kohl. Should identify items in the current federal budget that could be expanded and earmarked for conducting the modeling needed here, for example. This work would take more than a year to pay off if it is successful. (Brett Hulsey)
• USGS faces same pressure to cut monitoring every year, and that affects 50% match it can offer locals for monitoring (Peter Hughes)
• Could also request a mini study (6-8 months) to determine what modeling is really needed; then define data inputs and length of record needed (Peter Hughes)
• Really need overall hydrologic model of the watershed - sooner. Dane County ordinances regulate site development, and we also need to work regionally. We don't have a lot of time especially when we are rapidly developing. (Larry Nelson)
• Models should include alternative management practices. Could build on USGS work on the Pheasant Branch - agrees that we can't wait. We should be looking at having contracts for model preparation (watershed and hydraulic linked) in place within 6 months. Suggest parallel process used for development of Dane County Regional Hydrologic Study - oversight group, contributions from many participants. The effort we are talking about is as important as that. We need a model to grow with in the future. (Ken Potter)
• Need to engage development community in this. A short term action for the Commission should be to co-sponsor a forum for developers to hear presentations by Potter and others so they have the background. Fall is a better time because active construction will slow down.