Just reducing lake levels won’t prevent flooding. We need to do more.

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The narrative took hold before the waters receded.

The catastrophic floods that gripped the Madison isthmus in August were the result of high water levels on Lake Mendota. And the high water was demanded by marinas and owners of big boats and lakefront property. The culprits were the One Percenters.

Madison Mayor Paul Soglin joined in the chorus. “Maybe [more study] is needed to convince really dense people to lower the lake level a foot,” Soglin told the Wisconsin State Journal. “Our engineers know that if we keep Lake Mendota down a foot toward the lower end of the spectrum that even the kind of storm we had on Aug. 20 would not cause a problem.”

If Soglin is right then people like Ken Potter and Richard Lathrop are pretty dim bulbs. Potter is an emeritus professor of civil and environmental engineering at UW-Madison. His abridged CV runs to three pages of qualifications, honors and activities related to the study of hydrology. Lathrop is an honorary fellow at the UW-Madison Center for Limnology and is widely regarded as one of the leading experts on Madison’s lakes.

Neither Potter nor Lathrop believes that lowering Lake Mendota even by as much as a foot would solve the problem.

“Changing the lake level is not a panacea at all,” Potter says. In a big rain event like the one in August, “that extra space [in the holding capacity of the lake] would be filled up very quickly.”

Potter recommends creation of a small work group of experts to sift through various strategies, including the reduction of lake levels. But he believes that the biggest gains could be made by reducing runoff in urban development and replumbing large “closed depressions.” These are natural formations that used to hold water before agricultural practices and urban development caused them to drain into the lakes.

Lathrop thinks that the most gain could be made by allowing water to flow more easily south through the Yahara chain of lakes by clearing pinch points that now constrict the flow. He says he found the immediate reaction during and after the isthmus flood to reduce the level of Lake Mendota “a little frustrating.” He agrees with Potter that simply freeing up space to store water in the big lake without addressing broader issues in the watershed is missing the point. “Managing the lakes like they are a reservoir is not a good idea,” he says.

He and Potter agree that if the rate at which water can move through the system is not increased, then any additional storage capacity created by a lower lake level in Mendota will quickly be used up in major rain events and we’ll be back where we started.

And Lathrop believes that reducing Lake Mendota by a foot is untenable anyway because of political resistance and because of what it might do to current development and installations around the lakes. Lathrop thinks that a three-inch reduction, in coordination with other efforts, might do the trick.

These other efforts have been less talked about but they could go a long way toward preventing future flooding and improving the quality of our lakes.

James Tye’s organization is not primarily concerned with the amount of water in Madison’s lakes but in the water’s quality. The Clean Lakes Alliance, of which Tye is a founder and the executive director, is a coalition of business, civic and academic groups and individuals trying to keep the community focused on lake water quality.

Tye tries to stay out of the water level debates in part because they are so contentious. A quick look at his board reveals that lakeshore property owners are well represented. So, not surprisingly, he agrees with Potter and Lathrop, both of whom have also served on his board, that reducing the level of Lake Mendota is not the answer to flooding on the isthmus.

“Our position is that it’s all way more complex than just lake levels,” Tye says. “Reducing lake levels is part of the mix, but it’s not a silver bullet.”

Instead, Tye would like to leverage the debate about flood mitigation into a broader discussion of the water quality issues his organization has been working on for a decade. His answers are to reduce runoff into the lakes and to increase infiltration on the land in the watershed. Tye argues that those two fundamental strategies would not only reduce the threat of flooding but also stem the flow of nutrients and pollutants into the lakes, resulting in better water quality.

Tye and his organization supported an $18 million proposal in Dane County Executive Joe Parisi’s 2019 budget, which was approved by the county board this month. Key provisions, says Tye, include $8 million to permanently secure properties that help improve the county’s ability to reduce runoff; $750,000 to convert land to prairies and grasses to improve stormwater infiltration; $1 million in matching grants for repair of parks and trails damaged by the flood; a $500,000 fund for stream restoration; and $1 million added to the Urban Water Quality Grant Program.

Lathrop also is supportive. “These initiatives seem pretty comprehensive,” he says. “I’m particularly heartened that the first thing listed in the [county executive’s summary] was addressing ways to maximize water flow through the Yahara lakes system. This is where I feel the most emphasis should be placed, and not on a knee-jerk reaction to lowering Lake Mendota a foot below current summer minimum operating levels, or even lower to pre-settlement levels prior to the lake being raised by a dam.”

During an interview just before he released his plan, Parisi bristled at the idea that lake levels are being maintained at dangerously high levels to appease wealthy lakeshore property owners. “The power of the people who live on the lake is news to me,” he says. “The question is about much more than just lake levels. There’s no one easy fix to the challenge.”

Madison is also taking steps to address flooding. Its 2019 budget, approved on Nov. 14, added several million dollars in capital expenditures, including $775,000 for watershed, flood and planning studies, $1.17 million for land purchases, and $5 million for public works projects to address damage done by the August floods.

For this story I talked with Parisi, Tye, Potter, Lathrop, UW engineering professor Chin Wu, Madison City Engineer Rob Phillips and John Reimer, the acting director of the county’s Land and Water Resource Department and the guy charged with managing lake levels within the DNR range. From those discussions I tried to put together a comprehensive list of strategies that might prevent isthmus flooding in the future. With the exception of Lathrop, all were, to varying degrees, reluctant to weigh in too heavily on the Mendota lake level issue. They each saw it as a political flash point that obscured a more sober discussion of practical and comprehensive solutions.

It’s also important to be clear on what we mean by lake levels. When someone talks about reducing lake levels by a given amount we need to know what benchmark they’re working from. Lake levels are set by the state Department of Natural Resources in consultation with Dane County. For many years that level has been allowed to float within a 6-inch range during the summer before it is drawn down to a lower winter level before the lake freezes.

Some groups, like the local environmental organization CRANES, have called for that summer range to be lowered dramatically back to pre-settlement levels, which would be five feet lower than it is today. Others, like Soglin, have called for a still significant one-foot reduction from that range.

One proposal that Parisi initially endorsed, and Soglin strongly opposes, is to place caps on storm sewers in the isthmus area. City Engineer Rob Phillips says “that’s not a viable alternative.” He says that caps would not be water tight anyway, that this would require a system of pumps that would be very expensive, that it would create the potential for sinkholes, and that it doesn’t address the broader long-term issues.

With that as background, here is a list of what seem like viable options, with an analysis based on my interviews.

Move the water faster

Install big pumps below Lake Kegonsa to move water more quickly out of the Yahara chain of lakes. One fundamental natural problem is that the change in elevation between the lakes is small, meaning that water flows through the watershed at a relatively slow pace even under normal conditions. Big pumps could be installed to artificially boost the natural flow. But most experts I spoke with thought that installing such large and expensive pumps wasn’t practical and might not be necessary.

Clear several already identified “pinch points” that inhibit water flow out of the Yahara chain. Short of installing pumps, simply clearing the natural plumbing is Lathrop’s top strategy and it is featured prominently in Parisi’s plan. Mike Gerner, an accountant and board member of the Yahara Lakes Association Board (a group representing lake property owners), calculates that when the county concentrated weed cutting efforts at some of these points during the August flood event it increased flows by 244 percent. Gerner has an interest in strategies that wouldn’t make lakeshore owners extend their docks, but his calculation is consistent with the county’s own conclusion. Parisi’s proposal adds weed cutters to the county fleet.

Absorb the water better

Require all new development in the watershed to match storm water infiltration rates that were in place before building. Called “100 percent volume control,” the idea is to take the water that flows off buildings in large storms and move it into the ground, rather than into streets where it will flow into stormwater drains and then the lakes.

Republicans in the Legislature recently did the bidding of developers when they blocked local governments from implementing stormwater ordinances that exceed state requirements. But Potter points out that, “These DNR requirements were instituted for water quality purposes, not for reducing the flooding impacts of development.” It would take a change in state law to require more stringent requirements for runoff. It is too early to tell if the Evers administration will invest political capital in a move like this.

Require 50 percent volume control for redevelopment of properties with the watershed. This can be done now without a change in state law.

Restore the isolation of ponds and other wet areas. This is one of Potter’s favorite options. He explains that in the pre-settlement landscape, places like Esser Pond in Middleton were in the watershed but didn’t actually drain to the lakes very often. With urban and agricultural development these natural depressions were altered so that they now drain right into the lakes instead of allowing the water to stay there so that it can infiltrate into the ground.

Better manage stormwater runoff during unusually wet periods. “One such example would be reduction of the normal level of Esser Pond to enable its use for buffering water levels during periods of high lake levels,” Potter suggests.

Coordinate the response

The DNR sets the range of summertime water levels in Lake Mendota and it’s up to Dane County to manage the levels within that range. Changing the range is a fraught process. It takes a long time and inevitably involves a clash of interests. Previous attempts to lower the range have failed but only after a long and painful process.

But to think about this only in terms of the amount of water in Lake Mendota or, for that matter, to think of the problem only as affecting the isthmus, would be to get it wrong. Water management is a watershed-wide issue and, indeed, flooding occurred in areas all over the watershed. Moreover, we should be concerned not only about water quantity but also quality. In fact, until climate change made flooding a big concern, we usually only worried about things like algae blooms and beach closings.

So, in response to the new reality, Potter recommends a few institutional improvements.

The first would be a small work group of technical experts to quickly evaluate all of the strategies on the table and to recommend the ones that show the most promise to both reduce flooding all over the watershed and to improve water quality. UW engineering professor Chin Wu is widely credited with developing a computer model that can readily test each proposal. The modest Wu refuses to take the personal credit that the others assign him, but he confirmed that the “INFOS” system can accurately predict the impact of just about any idea.

Potter also recommends the creation of a “long-term watershed management entity that includes representatives of stakeholder groups, and that is powered with decision-making and funding authority.” He says that such an entity could also manage a county “runoff mitigation bank” — this would involve purchasing lands in the watershed to be used for infiltration and probably managed with prairie plants and any vegetation that would help absorb water.

Let me step out of my role as journalist and take on my role as a former mayor and a guy who cares a lot about his city. What everyone can agree on is that this summer’s isthmus floods are the result of climate change. Tye shared with me a stunning map, which shows that Madison is in the crosshairs of an historic increase in big rain events that cuts a swath through the Upper Midwest. One obvious need is to do something big and comprehensive about global climate change. We can hope that as the pace of climate disasters — floods, hurricanes, wildfires — accelerates, a grassroots political uprising will finally overtake the climate deniers and the multi-billion dollar fossil fuels industry. But even then, in the course of my lifetime, we can’t turn back the damage that has already been done. This problem is here to stay.

I get why some environmentalists, who I respect, want to dramatically reduce levels on Lake Mendota. Jon Becker of CRANES has written a detailed proposal calling for an immediate six-inch reduction followed by a steady lowering of two inches per year until the historic level is reached. That would be about a five-foot reduction over about three decades. Becker argues that the gradual lowering of the lake would give riparian owners and businesses time to adjust and that ultimately that would help restore the pre-settlement wetlands that helped with flood control, filtered water runoff and provided habitat.

But we also need to realize that that natural system also included wetlands that covered much of what is now the isthmus. Unless you want to submerge much of the Tenney-Lapham neighborhood and some of the Marquette neighborhood in knee-deep water, we have to accept that a certain amount of urban development is not going away.

Yes, we drained wetlands and maybe that was an historic mistake, but would you really want to trade the classic, walkable, tight-knit neighborhoods of the Madison isthmus to allow the waters to return?

Here’s what makes sense to me: Lathrop’s proposal to manage lake levels more aggressively in the lower range of the current DNR order, while we concentrate on the kind of double benefit in both quantity and quality that we can get from the kinds of things the Clean Lakes Alliance has been working toward for years.

There’s no question that Republicans in the Legislature are in the way of progress as they are on a wide variety of issues. They used to be for local control until they took over state government. Now, not so much.

The incoming administration of Tony Evers might be able to leverage some change, but it’s far from certain what they will be able to accomplish with a Legislature still firmly in the grip of the GOP. At least in the short-run — and some of what we need to do needs to happen soon — we’ll need to figure this out using the local powers we have.

What does not seem useful is to reduce this debate to yet another us-versus-them, haves-versus-have-nots, zero-sum argument between political tribes. There seems to be a half-dozen viable strategies to address the problem and among those only lake levels sparks a nasty local debate.

The available evidence suggests that we can stop or substantially reduce flooding by doing things that improve water quality overall and we can do it without a bloody debate over lake levels. If only “really dense people” look at it that way, then count me among the fools.

Editor's note: This article originally referred to Jon Becker incorrectly as Jonathan Becker.