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    EXTREME MAKEOVER VIOLENT WEATHER PRECIPITATES REDESIGN OF INFRASTRUCTURE By Anita Weier — Wednesday, June 18, 2008 The heavy rains, strong thunderstorms and
    Message 1 of 1 , Jun 24, 2008
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      By Anita Weier — Wednesday, June 18, 2008

      The heavy rains, strong thunderstorms and fierce tornadoes that have
      attacked the Midwest in recent weeks are a sign of the future, and
      communities will have to adapt to more frequent occurrences of
      extreme weather, experts say.

      It could be an expensive process.

      Ken Potter, a UW-Madison engineering professor who helped review the
      New Orleans hurricane protection system after Hurricane Katrina, said
      Wisconsin engineers will have to consider how to redesign structures
      to prevent flooding and events such as the draining of Lake Delton
      after extremely heavy rains.

      Some reservoirs, dams, levees, roads and bridges as well as water,
      sewer and stormwater systems will have to be rebuilt, and land use
      and zoning will have to change, researchers say.

      The design of sewer and water systems and stormwater detention ponds
      was based on past rainfall statistics and will probably require
      increases in capacity in the future, Potter said.

      "Water control structures were based on what was known in the early
      20th century. Much of our flood control and water structure was built
      in the 1920s and 1930s. The effect of development also has to be
      considered," Potter said.

      "The past may not be a good indication of the future."

      Though Potter and others stress that specific events such as recent
      intense rains and tornadoes can't be linked directly to global
      warming, those extreme weather events are consistent with
      expectations due to a buildup of heat-trapping greenhouse gases. A
      United Nations panel report on climate change compiled by hundreds of
      scientists internationally predicted that extreme weather events --
      such as heavy rain, heavy snow and heat waves -- will become more

      "For the Great Lakes region, the proportion of precipitation falling
      in extreme events has increased over the last 100 years" and is
      expected to increase even more in the next century, said John
      Magnuson, a UW-Madison emeritus professor who is an internationally
      known lakes expert. Steve Vavrus, as assistant scientist at the
      Nelson Institute for Environmental Studies at the university, found
      that days of 1-inch, 2-inch and 3-inch precipitation spiked in
      Madison during the current decade and that 1-inch precipitation days
      have risen steadily in each decade since the 1960s.

      But others, including Jonathan Martin, chair of the Department of
      Atmospheric and Oceanic Sciences at UW-Madison, stress that weather
      events are controlled by national-scale circulation patterns, and
      that global warming effects can't be judged on a regional scale at
      this point.

      Martin and others note that air current patterns across the nation,
      often influenced by temperatures in the Pacific Ocean and the amount
      of moisture carried in currents from the west and south, influence
      weather in Wisconsin.

      Rusty Kapela, a meteorologist with the National Weather Service in
      Sullivan, said seasons in Wisconsin that follow a "La Nina" time of
      colder equatorial waters in the Pacific -- as is the case this year --
      tend to have an above-average number of tornadoes.

      "We average 20 tornadoes in each of the 10 warm seasons that follow
      La Nina. This year we have had 16 so far," he said.

      However, Todd Ambs, director of the water division for the state
      Department of Natural Resources, noted the rainstorms that inundated
      southern Wisconsin early this month fit in with frequent predictions
      of extreme weather produced by climate change.

      "I grew up in Michigan, and I don't recall big low pressure systems
      just sitting over a region for days and dumping water," Ambs
      said. "Everybody said when Vernon County got 16 inches in 24 hours
      last August: a 100-year rain event. Now we had 11 inches in 24 hours.
      Something is going on."

      Potter said that although we don't know exactly what the future
      climate will be, it would be prudent to proceed by protecting
      Wisconsin from its greatest vulnerabilities, given the intensity of
      rain in recent years.

      "We have to be able to adjust," he said.\

      HOW TO ADAPT\ Municipalities in Wisconsin will have to upgrade water-
      related infrastructure -- including levees, sewer pipes and
      wastewater treatment plants -- in anticipation of more frequent
      downpours and floods, according to a 2003 report by the Union of
      Concerned Scientists titled "Confronting Climate Change in the Great

      Magnuson contributed to that report, which predicted that cities will
      be subject to more extreme storms and floods, exacerbated by stream
      channeling and more paved surfaces. The result will be greater
      property damage, heavier burdens on emergency management, and
      increased cleanup and rebuilding costs, unless changes are made.

      Patrick Eagan, an engineering professor at UW-Madison who is an
      expert in stormwater management and potential effects of climate
      change, said good water management is the key to handling shifts of
      normal weather patterns.

      The more developed our landscape becomes, the more runoff we will
      have, he said. So reducing runoff with rain gardens, porous pavement,
      grass swales and green roofs will be important.

      "If we have more runoff, our design standards for storm sewer systems
      have to change. Our pipes and culverts are undersized," said Dick
      Lathrop, a DNR scientist who is working with Magnuson in a new state
      program planning how the state can adapt to climate change.

      The Department of Transportation will have to look at vulnerable
      situations where roads might be washed out, to prevent runoff from
      eroding them, he added. Yet, the DOT can barely keep up with places
      that are already damaged, according to Lathrop.

      Smarter planning and zoning also will be essential.

      For instance, topographic information about Lake Delton should have
      been known, so people realized where water would go when the lake got
      to a certain height, Potter said.

      The lake broke through a county highway and headed to the Wisconsin

      "Dams and reservoirs are designed to pass such events, and this dam
      and reservoir could not," Potter said. "And this was not a maximum
      flood that would involve rainfall of 20 inches."

      State and federal regulations for high-hazard dams look at the whole
      lake, not just a dam, he said.

      "You don't let water spill out. You reinforce places where it might
      go," Potter added. "Many dams and reservoirs have levees, and it
      might have been a real cheap fix to put rip-rap there. That might
      have been possible to do for tens of thousands of dollars. That would
      not have cost nearly what it will cost to fix it."

      It also might be logical to keep Lake Mendota at lower levels than
      present in order to preserve wetlands and give the lake a bigger
      storage capacity in case of bigger storms, Magnuson suggested.

      Additionally, the whole notion of where you build also will have to
      be considered, Eagan said.

      "It makes no sense to build in floodplains where you get flooded over
      and over again. It doesn't help the people and costs social money
      that could be spent on other things," Eagan added.

      A house in such an environment is a risk, he said.

      The cost of bringing infrastructure up to higher standards that will
      survive stronger weather will depend on how much is done and how far
      the work goes.

      "It depends on how good of shape it was in and how conservatively it
      was designed," Potter said.

      "It's expensive, but there has been discussion for a decade or more
      that a lot of this has to be refurbished anyway, because
      infrastructure is aging. For years we have shortchanged
      infrastructure requirements. We have to do something, so the real
      decision is how much we believe floods will increase and the results.
      We should look at what is the most critical need and what is the most

      When calculating the cost and standards of building, officials also
      should consider the high cost of repairing or replacing a bridge,
      road, dam or lake that fails, Potter warned.

      Lee Sensenbrenner, a spokesman for Gov. Jim Doyle, said state
      officials have their hands full at present working with the Federal
      Emergency Management Agency to deal with current damages. They are
      counting on federal funding to take care of much of the flood damage
      to agriculture, homes and public infrastructure, so broad questions
      about the future will have to wait.

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