More rooftops, more driveways and more streets can mean more rain running off the land. Is that bad for lakes? Is this runoff regulated? These are questions being asked as development increases around lakes. Let’s look at how runoff, often called stormwater, can affect lakes, as well as some of the new stormwater regulations that apply to residential development in Wisconsin. The information here is a general introduction to the rules and does not cover all of the requirements. Interested readers should review the entire Wisconsin Administrative Code NR 151 - Runoff Management.

Stormwater is the rain that runs off land because it cannot enter the ground as fast as it falls. We have probably all observed this water running along streets or off of roofs, but you may be surprised to learn how much stormwater can be generated. For example, a single 2 � inch storm on a 2,000 square foot roof can generate more than 3,000 gallons of water. Over the course of an average Wisconsin year, that single roof can generate almost 40,000 gallons of water.

From a lake’s perspective, the water in rain (and snow) is very important. Without new water to replace the water that drains to streams or flows over dams, lake levels would fall. In Wisconsin, much of this new water comes from rain and snow throughout the watershed. It infiltrates the ground and then travels to lakes and streams through the groundwater. Stormwater can short-circuit this path and deliver a lot of water to the lake in a short period of time. This stormwater carries sediment and nutrients such as phosphorus that would otherwise be removed. More nutrients and sediment mean more algae and plants in the lake. While some of these are necessary for a healthy lake, too much means greener water, lower oxygen and other undesirable changes.

The earliest attempts to manage stormwater focused on the flooding associated with large storms. Stormwater regulations usually require that the peak (high) flow that occurs from a large storm not exceed that which occurred prior to development. Of course, measurements are not usually made before and after the change, but designers estimate the peak flow likely before and after development. They base these calculations on single, infrequent storms, such as those likely to occur once every two, ten or even one hundred years.

From the lake’s perspective, reducing the peak flow from large storms is very important. These high flows can carry sediments and nutrients from soil and vegetation directly to the lake. However, if a pond or detention area is used to slow the movement of water, it may not reduce the overall stormwater volume. If the stormwater volume is not reduced, there will still be more sediment and nutrients travleing to the lake than before development. Fortunately, other Wisconsin stormwater requirements also try to address the increased sediment and runoff volume.

When rain falls on undisturbed land, much of it infiltrates into the ground. This infiltrated water is available for plant use and can move down to the groundwater. The water quality is improved when sediment and nutrients are removed as the water percolates through the soil. Perhaps most importantly, infiltration reduces the volume of water that leaves the land as stormwater runoff. The new Wisconsin stormwater regulations require that some of the runoff generated from development be infiltrated. This is a new approach to regulating stormwater that tries to mimic the movement of groundwater and filtration that occurs naturally.

The regulations require residential projects that disturb more than one acre to maintain almost the same amount of infiltration before and after development. Specifically, the designer is required to infiltrate at least 90% of the water that previously infiltrated. In contrast to the single large storm approach of the peak flow rules, the infiltration requirement looks at all of the storms during a typical year. In Wisconsin, that means designers must consider the more than 100 rain storms, most of them small, occurring in the average year. There are a variety of approaches available to infiltrate this stormwater, including such things as rain gardens.

The movement of runoff across rooftops and roadways results in stormwater becoming contaminated with sediment and nutrients. Another requirement of the new stormwater regulations is removal of sediment from the stormwater. For development that disturbs more than one acre, methods must be installed that would remove 80% of the sediment before the water is released. Because sediment is denser than water, one of the approaches to this treatment is to pass the stormwater through a pond and allow the particles to settle to the bottom. Periodically, the pond would be cleaned to remove and dispose of the sediment.

Development around lakes always poses a risk that nutrients and sediment on the land will be more quickly transported to the water through increased stormwater runoff. Fortunately, there are many techniques available to reduce the volume and improve the quality of stormwater runoff and thereby reduce the impact to lakes. While the new Wisconsin regulations begin to address stormwater, some challenges remain.

One of the challenges to lakes is that the regulations do not apply to all development that occurs within a watershed. If the disturbed area is less than one acre, it may still generate runoff, but it may not be covered by the new regulations. Of course, designers and builders can still incorporate stormwater management into the construction. A related challenge is that it is not always clear how the regulations will apply to single lots that are part of larger developments. If land in the development is subdivided and then individual lots disturb less than one acre, each lot may not have to meet infiltration or treatment requirements.

Another challenge to protecting lakes is that the regulations allow some exemptions from the requirements when the infiltration rate is slow, or the area for infiltration requires too much land. In those cases, the increased runoff volume will most likely increase the sediment and nutrients delivered from the site.

Finally, the regulations do not specifically address nutrients such as phosphorus. Many Wisconsin lakes will have poorer water quality if phosphorus levels increase. Fortunately, the regulations indirectly address nutrients by reducing runoff volume and sediment loading to the lakes; however, just meeting the regulations does not eliminate the possibility of increased nutrient delivery to lakes.

The Wisconsin stormwater regulations provide some basic guidance on managing development to protect lakes—infiltrate and treat the stormwater, and prevent large storms from eroding and carrying sediment to the lake. Of course, rules alone do not ensure that site development will incorporate these principles early enough to take full advantage of opportunities to reduce runoff volume. Incorporating infiltration into development is new to most of us. The planning for stormwater management needs to start early in the development process to identify those areas best suited for infiltration and then protect those areas from compaction during construction. This planning for infiltration, treatment and reduction of peak flows may require coordination of site planning and design activities in ways that development did not have to consider in the past.

The runoff management philosophy in the new Wisconsin stormwater regulations should encourage all lake residents to think about how changes they make to the land can alter runoff generation and movement. How can you change the way stormwater is generated or managed to reduce the impact on the lake? The goals of the Wisconsin runoff regulations—reducing runoff volume, infiltrating runoff and treating water that must leave the site, can be incorporated into individual residential lots through reductions in impervious surfaces, redirecting runoff to areas where the water can infiltrate, and encouraging infiltration by reducing compaction and constructing rain gardens.

A typical rain garden is a perennial plant bed sunk 4-8 inches deep with a flat bottom. Most are from 75-300 square feet in size, roughly 1/4 to 1/3 the size of the area collecting water (rooftop, driveways, hillside, backyard, etc.). Crescent, kidney, and teardrop shapes work well for the form of a rain garden.

The cost of installing a rain garden ranges from $11-$13 per square foot for all facets of the project, to smaller amounts ($5-$6 per square foot) for those willing to do some site preparation and planting themselves.

To calculate the proper size of your rain garden, simply measure the area of the roof, driveway, yard area, or other spot from which you want to collect rainwater. For example, if you had a roof 25 feet wide by 40 feet long, that would give you an area of 1,000 square feet. Most rain gardens are 25-33% the size of the area being collected from, so in this case, make your rain garden 250-330 square feet. Place the rain garden at least ten feet away from the foundations of buildings and not over septic systems or lateral sewer piping. Stay away from big trees (and their roots) and high-traffic areas. Full sun is best for site selection but partial shade spots can work effectively as well. Avoid areas where water already collects; infiltration from these sites is poor. Remember to call Digger’s Hotline (1-800-242-8511) before you start.

Native plants are best for rain gardens because they provide assorted benefits to the landscape. Most native plants have roots that grow down twice as deep as the plants are tall, making them efficient at absorbing water. The root penetration by these plants opens up small channels for water to move into, increasing the amount of infiltration. Small insects, butterflies, birds, and other critters use the vegetation as a food source, overwintering area for larvae, cover, nest making material, and additional services.

Choose plants appropriate for the soil conditions and for the given amount of sunlight. Plan for staggered blooming times so you have color in spring, summer and fall. Be sure to include native sedges and grasses. You might add nectar and food sources for butterflies, too. Remember to plant the green side up, and you will help create an effective stormwater control measure and important habitat for local wildlife.

For site selection information, building guidelines, size calculating, and plant selection ideas, visit the UW-Extension website at:

http://clean-water.uwex.edu and WDNR website at: http://www.dnr.state.wi.us/org/water/wm/nps/rg.

-Five Man Electrical Band - 1972

The lyrics may be somewhat dated, but the message is as clear today as in the ’70s: signage overload! Everywhere you look – highways, parking lots, residential front yards and even waterfront shorelines – signs are littering the scenery. Each sign intends to inform or remind us of some opportunity or activity we might otherwise forget. The best signs function as a prompt, not to change attitudes or increase motivation, but rather to remind us to engage in an action that we are already predisposed to do. What about signs at the boat landing? Are they effective in changing boater behavior?

Beginning in 2002, WDNR was mandated by Wisconsin Act 109 (which established a statutory framework for the comprehensive state aquatic invasive species program) to post signs at public boat landings, both at launch sites and near the access area exits. There are three signs used by WDNR to inform the public about aquatic invasive species (AIS):

The initial signage efforts focused on the access sites with the highest use and proximity to infested waters, as well as non-infested waters. Eventually every public landing will be posted but to date, 85% of all infested waterbodies (totaling 1,902 boat landings) are posted with signs. In total, there are 3,874 signs warning boaters about AIS and reminding them that it is illegal to launch with aquatic plants and zebra mussels attached.

According to 59,000 watercraft inspection surveys from 2002-2006, only 12% of boaters recalled seeing AIS information at the landing, while 44% remembered talking to a watercraft inspector about invasive species. Does this mean signs are too small? Poorly designed? Improperly located at the launch site? The answer could be yes to all, depending on the boat landing you visit. While signs are excellent prompts to target a specific behavior change (especially if they are graphically vivid, explicit in message and positioned in close proximity to the target behavior), many boat landings are too limited in space, narrow in design and already overloaded with informational messages. Still, some communities are focusing their AIS prevention strategies on additional signage, bigger and more graphic than existing designs posted by WDNR. Why are we putting up more signs?

For example, a boater at Lake Metonga in Forest County could not recall if Metonga contained zebra mussels even though a large sign with vivid graphics and bright lettering was right behind him. Other communities, like the Town of Plum Lake in Vilas County, have integrated their signs and message with a national campaign called, Stop Aquatic Hitchhikers!^TM Integrating a national campaign logo with local information provides instant recognition for boaters who often cross state lines.

The watercraft inspection surveys have shown after four years of AIS education, 72% of surveyed boaters take prevention steps and clean their equipment when leaving a landing and 70% are aware of the illegality of launching with aquatic plants or zebra mussels attached to the boat. Should your community consider additional signage at the landing to educate boaters?

According to Doug McKenzie-Mohr and William Smith, authors of Fostering Sustainable Behavior: An Introduction to Community-Based Social Marketing, no information strategy will be successful if a behavior change is inconvenient, unpleasant, costly or time-consuming. So before you spend a dime on a new sign, take an inventory of what is currently at the landing, optimize what little space is available and make every effort to make it easy for a boater to check their boat after leaving the landing.

Most importantly, participate in the Clean Boats, Clean Waters volunteer watercraft inspection program. While signs can give information, personal contacts provide major influence on boater behavior and attitudes.

• Before you do anything at the landing, make sure you know who owns the landing, and ask for permission before you add or remove anything!

• If the landing is posted with Wisconsin signs, make sure the existing signs are properly placed. The green/white or yellow sign should be close to the launching site and the "Stop" signs should be visible when a boat is exiting the landing. If your landing is not posted, contact a WDNR service center for free signs.

• Remove any old, outdated or broken signs. If several signs contain the same message, consolidate into one sign. Keep the message short and use graphics; the less text, the better. For sign examples, visit the Clean Boats, Clean Waters website (see below for web address).

• If you have a kiosk, order and stock current AIS pamphlets. See the Clean Boats, Clean Waters website for publication choices.

• Provide a staging area for boaters and watercraft inspectors to check/clean boats away from the launching area and shoreline. If electricity and water are available at the landing site, provide a portable sprayer to rinse boats.

• Designate a "weed disposal" area, away from the water’s edge.

Stop Aquatic Hitchhikers!^TM - www.protectyourwaters.net

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Mapping the Spread of Eurasian Watermilfoil

For over 40 years, Eurasian watermilfoil (EWM) has caused mischief in Wisconsin’s lakes. Although some anecdotal reports suggest this non-native submersed aquatic plant species was here in the 1930s, it is possible that native milfoil species may have been mistaken for EWM.

The first documented, positively identified infestation of EWM was in Avoca Lake near the Wisconsin River in Iowa County in 1965. Other early infestations included Pewaukee Lake (1966); Lake Mendota and Fish Lake near Madison (1967); Lake Butte Des Morts near Oshkosh, Lake Wingra, Green Lake, Lake Five near Merton, and some of the open water areas of Horicon Marsh (1969).

Since then, EWM has continued to spread across the state. Southeast Wisconsin, with many lakes that are heavily used by recreational boaters, was the first geographic region to see multiple EWM infestations from the late 1970s into the early 1990s. While the spread of EWM across the rest of the state has been more gradual, since 2000 a greater number of new EWM infestations have been found in the northern half of the state than in the south.

EWM is now a greater threat in northern Wisconsin where the majority of lakes are located but where the fewest EWM infestations have been found. The map shows the geographic spread of EWM into new areas of the state. Currently, 466 EWM infestations have been verified, including 420 inland lakes, 15 inland river segments, 20 Great Lakes bays and harbors, and 11 interstate river segments (consisting of the Mississippi and Menominee Rivers).

Each new location of EWM can become a local source lake from where EWM may radiate to nearby lakes. For example, EWM was first found in Beaver Dam Lake in Barron County in 1991. The plant is now found in nearby Duck, Echo, Kidney, Sand, and Shallow Lakes. Because EWM travels with boaters and anglers, it is very important that all plant fragments are removed from motors, trailers and gear such as anchors.

Lake organizations are strongly encouraged to have volunteers trained in the Clean Boats Clean Waters program and start inspection programs at their boat landings. Prevention remains the most effective and cost efficient way to control EWM. Once the plant is established in a lake, management options are limited, and EWM has never been successfully eradicated from a lake. If EWM arrives, a lake organization should immediately begin thinking about long-term management and develop an Aquatic Plant Management Plan.

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Predicting Boater Behavior: Survey Says...

Lake Districts Q&A

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What's in a Name?

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Congratulations Graduates!

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Calendar

February 1, 2007 – Application deadline for Lake Planning and Aquatic Invasive Species Control Grants. Contact your DNR Lake Coordinator for more information.

February 1-2, 2007 – 12^th Annual Wetland Science Forum, La Crosse.  For more information: www.wiscwetlands.org

March 3-5, 2007 – 27^th Annual MAPMS (Midwest Aquatic Plant Management Society) Conference, Milwaukee. For more information: www.mapms.org

March 16, 2007 – Lake Stewardship Award Nomination Deadline. Nominate an individual or group who dedicates time and talent to Wisconsin’s waters for this prestigious award. For more information: www.uwsp.edu/cnr/uwexlakes/conventions

April 26-28, 2007 – 29^th Annual Wisconsin Lakes Convention, KI Convention Center, Green Bay. For more information: www.uwsp.edu/cnr/uwexlakes

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Reflections