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Seawalls and Your An eroding shoreline can be a big headache for lakeshore homeowners. After all, you’ve spent a premium for your lakefront property and you’d like to keep it in place. What can you do? More importantly, what can you do without adversely affecting your lake and your property value? The objective of lake shoreline protection techniques is to stabilize and protect these land forms against scour and erosion from forces such as wave action, ice action, seepage, and runoff from upland areas. Shoreline stabilization methods fall into two broad areas: 1. nonstructural (vegetation) 2. structural a. flexible (rip-rap, glacial stone) b. rigid (seawalls)

Vegetation Vegetation effectively controls runoff erosion on slopes or banks leading down to the water; however, it is less effective against direct wave action or seepage-caused bank slumping. Grasses are effective on slopes flatter than 3:1 (three feet horizontal run for each one foot vertical rise). On steeper slopes, deep-rooted grasses, woody shrubs, or trees are more effective. Bioengineered materials (erosion control mats, biologs, etc.) may be used to stabilize slopes while the vegetation is becoming established. Benefits of a vegetated shoreline are numerous and include: • Great habitat for aquatic organisms that live on the edge •A barrier to Canada geese (they won’t walk through tall grass, shrubs, Fall 2003 or other dense vegetation) • Shade, which discourages dense growth of aquatic plants (such as Vol. 15, No. 3 Eurasian watermilfoil) along the lakeshore.

Flexible Structures Rip-rap (preferably with natural, glacial stone), when properly installed, provides effective, long-term shoreline protection from waves, ice action, and bank slumping caused by seepage. Unfortunately, such structures are seldom installed properly but we’ll address this in a future issue of WaterColumn. A glacial stone revetment is Natural vegetation can protect even steep lakeshore slopes. “flexible” because waves move the stones slightly and flow over and into spaces between the stones, which dissipate the

ater Colum erosive energy of the waves. An additional ecological advantage of glacial stone is that aquatic insects (food for young fish) find shelter between the stones and rooted plants can grow within the stones, providing a more natural appearance.

Clean Program • Office of Water Quality • Department of Environmental Management

W many ecological problems for lakes. 1. Reflected wave energy scours the reflection lakebed along the seawall, and dissipation seawall waves with it, scours rooted plants waves important as habitat for fish, aquatic insects (fish food), and refuge amphibians. scour 2. Wave scouring also resuspends sediments, increasing turbidity in the lake. Glacial stone rip-rap dissipates wave 3. Wave scouring stirs up sediment Seawalls reflect waves, which scours out energy and is habitat for many aquatic the lake sediments. organisms. phosphorus, increasing algae growth. 4. Seawalls are a barrier for frogs Seawalls leaving the water after breeding. that drew them to the water in the Seawalls are rigid structures They can’t get out and may first place. This is seen in declining that do not move when waves actually drown. property values. For example, a strike them. Wave energy instead is study in Maine has shown that a reflected back into the lake and To prove the ecological value of three-foot decrease in Secchi disk down along the shore. They are glacial stone vs. seawalls, 17 transparency (water clarity) used where steep banks prohibit cooperative lakefront landowners dropped the average selling price of the forms of protection suitable on on Lake refaced 1,000 homes by $7,500 - $14,000 per 100 shallow slopes. The seawall is feet of seawalls with glacial stone. feet of lakefront property. A 2002 placed vertically in soils and forms One-year results showed fish study in Minnesota came to similar a barrier between the land surface diversity increased by 36%, rooted conclusions. A three-foot decrease in and the water. The seawall itself plants present at 81% of the sites, water clarity on Leech Lake can be constructed of sheet pile, and aquatic insect diversity and dropped property values by $594 wood, or concrete. Proper seawall abundance were doubled at the per foot of frontage. A three-foot construction requires: (a) refaced sites. improvement in clarity increased anchoring either by driving the Economic values also become property values by $423 per foot of pile deep into the ground or the important when considering frontage. Therefore, building a placement of “deadman” anchors shoreline management. People are seawall may not be the best way to and (b) protecting the “toe” of the willing to pay a premium price for maintain your property’s value. seawall with large stones to prevent lakefront property because of the undercutting. Seawalls not properly benefits of living on the lake. These What Does This Mean for constructed may quickly begin benefits include the scenic beauty, Lakeshore Homeowners? leaning toward the water due to peacefulness, swimming, fishing, You’ve paid a premium price back-pressure. watching birds, and others. But for your lakefront property. If your While many lakeshore installing seawalls is an action of shoreline is eroding, of course you homeowners apparently appreciate lakefront homeowners that need to fix it. However, before you the looks of seawalls, they pose actually degrades the very qualities do anything, you should first have

Concrete seawall Proper construction of a seawall Wooden seawall

Fill Cap

Original Sheet pile ground surface Wale

Tie-back

Anchor (deadman)

2 a comprehensive evaluation of the includes information on the health It is important to note that a cause of the problem. Once the risks and health benefits of eating fish advisory on a body of water cause is determined, work with fish and the proper cleaning and does not necessarily mean that the your lake management professional preparation of fish. This water is unsafe for other to select the best corrective action publication is available annually recreational activities. If the water for the problem . . . one that also through cooperative efforts posed a hazard to human health, has the minimum impact on the between the Indiana State there would be a separate advisory lake. Seawalls should only be used Department of Health, the Indiana issued for recreational activities like when the eroding lakeshore is Department of Environmental swimming or skiing. Requests for a steep, with high banks, and high Management, the Department of free copy of the 2003 Indiana Fish wave energy. You don’t need a Natural Resources, and Purdue Consumption Advisory and seawall to repair minor erosion or University. questions about eating sport- in low wave energy situations and, “We have tried to include caught fish can be directed to the in fact, you may actually do more everything a person might want to Indiana State Department of damage to your lake than good. know about eating sport-caught Health, at (317) 233-7055. For more information, contact fish in Indiana,” said LaNetta Information from the 2003 Fish your county Natural Resources Alexander, environmental Consumption Advisory is available Conservation Service, an agency epidemiologist at the Indiana State on the Web in two ways: by body within the U.S. Department of Department of Health. “The of water and by county (from a Agriculture. They have technical advisory is designed to provide Web site prepared by Purdue manuals and expertise to advise people with guidelines on how University). Both versions are you on proper lakeshore erosion much and how often they should available at http://www.IN.gov/ control. You may also contact the eat the fish,” Alexander said. “By isdh (click on “Data and Indiana DNR, Division of Soil following the advisory and eating Statistics”). Other available Web Conservation; Web site: http:// fish in moderation, you help avoid resources include: www.ai.org/dnr/soilcons/. the risk of accumulating •mercury information, at http:// contaminants in your body over www.in.gov/idem/mercury/ Sources of Information time and gain the benefits of a •a mercury fact sheet, at http:// Used in this Article protein source that’s low in www.in.gov/idem/mercury/ McComas, S., D. Jansen, J. Marter, saturated fats.” prevention/mercfact.pdf and D. Roseboom. 1986. The advisory is not meant to •a polychlorinated biphenyls Shoreline protection. Lake and discourage fishing, but rather to (PCBs) fact sheet, at http:// Reservoir Management, Vol. maximize the benefits and www.in.gov/idem/macs/ 2:421-425. minimize the risk of eating Indiana factsheets/media/pcbs.html McComas, S. 2003. Lake and Pond fish, she said. The fish advisories Management Guidebook. Lewis are based on fish tissue sampled by Publishers, Boca Raton. the Department of Environmental IDNR. 1997. Lakeshore Protection Management; the agency gathers in Indiana. Lake and River data on fish during its annual Enhancement Program, Division watershed assessment sampling. of Soil Conservation, Mercury and polychlorinated . Available online at: biphenyls (PCBs) are the major WATER COLUMN http://www.ai.org/dnr/soilcons/ contaminants that can be present Published quarterly pdfs/seawall.pdf. in the tissues of Indiana fish, by the Indiana Clean Lakes Program although pesticides and heavy as a medium for open exchange of metals can also be present. information regarding lake and State Issues 2003 “The Fish Consumption watershed management in Indiana Advisory is a tool everyone who William W. Jones, Editor Indiana Fish eats fish caught from Indiana waters should familiarize Address all correspondence to: Consumption Advisory themselves with,” said Department SPEA 347 of Environmental Management 1315 E. Tenth Street The Indiana State Department of Indiana University Health has issued the 2003 Indiana Commissioner Lori F. Kaplan. “By Bloomington, IN 47405-1701 Fish Consumption Advisory—both putting this critical information in E-mail: [email protected] in print and on its Web site. In the hands of Hoosier fisherman and fish consumers, these agencies Phone: (812) 855-4556 addition to fish consumption FAX: (812) 855-7802 advisories for Indiana waters, the are helping them make important Fish Consumption Advisory decisions about their health and the health of their families.” 3 Coroner Cites Algae in Public Awareness this toxin from animal studies,” he Coroner Stanley said he said in an interview. “If it had been Teen’s Death . . . decided to release the report to Anatoxin-a poisoning, he would make the public aware of the have experienced those symptoms Experts are Uncertain potential dangers of algal toxins in within a few hours. In animals, you small ponds anywhere, whether at see the effects within minutes to an About Toxin’s Role golf courses, farms, or parks. hour or two.” After a yearlong investigation, the “There are a lot of ponds out “Otherwise, the evidence Dane County, WI coroner has there with a lot more algae than points to anatoxin,” Carmichael concluded that the mysterious was in this one,” he said. “We said. “It’s still puzzling to me.” death of a Cottage Grove teenager wanted the public to know that Stanley, the coroner, defended last summer likely was the first in you should not go swimming in his conclusion. “The only thing the nation caused by exposure to a algae-covered ponds. Parents that didn’t fit was the timeframe, toxin released by algae. should even be cautious not to let but these kids may have had a Two days after swallowing children collect golf balls from golf stomachache or diarrhea before water while splashing and diving course ponds.” they told their parents,” Stanley in a scum-covered pond at a Dane Still, there is no reason for the said. “Anatoxin is the most County golf facility in July 2002, public to panic about the presence reasonable cause of his death with Dane Rogers went into shock and of the toxins, according to Stanley the available information.” suffered a seizure before his heart and other investigators. While failed, according to Coroner John blue-green algae are common in Confounded Investigators Stanley’s report. surface water, toxins are released At the time, Rogers’ sudden Another teen, unnamed in the only after thick blooms occur in death confounded medical report, also was in the pond with summer. The toxins are diluted investigators. An autopsy by Robert Rogers and later became sick, significantly in lakes, rivers, and Huntington III of the University of complaining of severe diarrhea and reservoirs and can be removed by Wisconsin-Madison Medical School abdominal pain. He survived. Tests conventional drinking water offered no explanation. “This of blood and stool samples from treatment plants. young person crashed and died both boys found the common One international algal toxin after onset of nausea and blue-green algae, known as expert who participated in the vomiting,” Huntington said in a Anabaena flos-aquae, and its toxin, investigation is not 100% report. “We see acute heart Anatoxin-a. “Never in a million convinced that Anatoxin-a caused damage.” years did we think something like Rogers’ death. Wayne Carmichael, Huntington’s conclusion: “This this could happen,” said his father, a professor of toxicology at Wright is a sad and vexing case.” A series Mike Rogers. State University in Dayton, Ohio, of laboratory tests for pesticides, Kim Rogers, his mother, still has studied toxins released in algal parasites and other illness-causing recalls the evening of July 14 last blooms throughout the world. His organisms found no clues. Analyses year. “It was 97 degrees that day,” laboratory received tissue, blood, of brain tissue ruled out meningitis she said. “It was just getting dark, and other fluid samples from the and encephalitis. and they decided to cool off in two boys, which were tested for Subsequent interviews with the there. I can just picture them several algal toxins. teenager’s friends and fellow soccer jumping in the water. Our one Based on animal studies, teammates revealed that Rogers wish is that golf courses would be Carmichael said the amount of and four of his buddies—about 48 required to put a sign up at ponds, Anatoxin-a found in the samples hours before his death—had warning of toxins in the water,” could have caused the diarrhea and jumped a fence at Vitense Golfland she said. seizure followed by rapid death. on the Beltline Highway in Dane Rogers was 17 at the time There are no other cases of human Madison so that they could cool off and looking forward to his senior deaths caused by Anatoxin-a for in the pond. year at Monona Grove High comparison, however, he said. “They were in there horsing School. He was captain of the The reason that Carmichael around,” Stanley said. “Pushing school’s soccer team and honored doubts this explanation is the each other around and wrestling in as an all-conference goalie, and a length of time that elapsed—48 the water.” While wrestling and member of both the National hours—between the boys frolicking diving, Rogers and one of the other Honor Society and French Honor in the pond and Rogers’ sudden boys had their heads underwater Society. “He was an all-around death. for varying lengths of time, good kid,” said his mother. “We’re confident the toxin was according to statements made by present, but the time of death does the teens. “They both got a not fit into what we know about mouthful of water,” Stanley said. 4 The other boy who had been mouth reports tell otherwise, and can increase the growth of rooted fully submerged became ill with many homeowners are eager to try aquatic plants, and may induce the same symptoms of acute this inexpensive, chemical-free fish kills if decomposition of the diarrhea and abdominal pain, the algae remedy. The EPA has recently barley straw reduces the dissolved coroner said. The remaining three begun enforcing rules that prohibit oxygen levels in the pond. Proper developed only minor symptoms. commercial vendors from selling dosage is critical. The four survivors described the barley straw specifically for algae small pond to investigators as control. The EPA defines a pesticide Source: FX Browne, Inc. Lake and “dirty” and “scummy.” as “any substance or mixture of Watershed News It was nearly two weeks after substances intended for Rogers’ death before researchers preventing, destroying, repelling, became aware of the pond as a or mitigating any pest.” If a claim potential source of a toxin or other is made that barley “controls” algae cause of diarrhea. Water samples (a pest), it is legally considered to Meetings were collected on July 26 that year, be a pesticide. However, no but studies were inconclusive. The company has ever registered barley October 20-23, 2003. 3rd samples were tested by the State straw for use as a pesticide. National Conference: Nonpoint Laboratory of Hygiene in Madison Therefore, barley straw cannot be Source Pollution Information & and the Madison Department of sold as a pesticide to control algae. Education Programs, Congress Public Health. The city laboratory This means that commercial Plaza Hotel, , Illinois. found no illness-causing bacteria. applicators (individuals who have Cosponsored by: Chicago The state laboratory found no algal been state certified to apply aquatic Botanic Garden and U.S. toxins. pesticides for hire) and lake Environmental Protection Nonetheless, Stanley concluded management specialists cannot Agency. Contact: Bob Kirschner; that the evidence linked Anabaena recommend or apply barley for e-mail: and anatoxin to Rogers’ death. algae control; this application [email protected]; Diarrhea resulted from would be the same as distributing Web site: http:// “incidental ingestion of the water an unregistered pesticide. www.chicagobotanic.org/ from the pond,” he says in an Similarly, garden centers and research/conference/nonpoint. addendum to his original coroner’s Internet companies cannot market report. barley straw as an algae control November 2-4, 2003. American product. They can, however, sell Water Resources Association Source: Sept. 6, 2003 editions of the barley straw for non-pesticide Annual Conference, Hilton San Milwaukee Journal Sentinel usage, such as for water Diego Resort, San Diego, CA. clarification. Individual Web page: www.awra.org homeowners may apply so-called “home remedies” such as barley EPA Considers Barley November 4-8, 2003. NALMS straw to any water garden or pond 2003: 23rd International that is on their property since Straw a Pesticide, Symposium of the North American privately owned water bodies do Lake Management Society, not fall under EPA jurisdiction. Cracks Down on Foxwoods Resort, Mashantucket, Private landowners may not apply CT. Contact: Phone: (608) 233- Distribution barley straw to any public lake or 2836; Fax: (608) 233-3186; e- pond. These waters fall under state Barley straw has been endorsed by mail: [email protected]. environmentally conscious regulations. For more information managers as a remedy for on the EPA’s stance on aquatic controlling nuisance algae in pesticides, visit http:// ponds. Now the EPA is cracking www.epa.gov/compliance/ down on companies trying to sell resources/newsletters/civil/enfalert/ barley straw, claiming it is an registration.pdf. unregistered pesticide. If one chooses to try barley Got a question about straw as an algae control on their Bales of barley straw have been your lake? Or lakes in general? used to inhibit algal growth in own private lake or pond, they small ponds. In the US, the results should take into consideration that Or about something have been mixed, with most even the strongest proponents of you’ve read? Write to us at the official studies showing no the remedy do not claim that Water Column and we will do beneficial reduction in the algae barley straw inhibits all types of our best to answer it. population. However, word-of- algae. Also, the use of barley straw 5 2003 NALMS Full and half-day workshops • Aquatic Plants—An Identification include: Workshop Symposium to be Held • Aquatic Ecosystem Restoration • Basics in Limnology • GIS for Conservation Planning • Conservation Marketing for the in Connecticut • Fish Assemblage Status & 21st Century The New England Chapter of the Identification in Northeastern US • Ecology & Control of Nuisance North American Lake Management Aquatic Habitats Algae Society is pleased to be hosting the • Internal Phosphorus Loading • Education & Outreach Strategies society’s international symposium • Low-Impact Development & • Touring Your Watershed Using November 4-8, 2003 at Foxwoods Ecosystem Restoration GIS Resort in Mashantucket, CT. • Alum for Phosphorus Designed for lake and watershed Inactivation & Interception Please see the NALMS Web site professionals and citizen stewards • Taxonomy & Identification of (http://www.nalms.org) for more alike, this event features diverse Algae information, for a complete list of pre- and post-symposium •TMDL Modeling technical sessions, and to register. workshops (open to non- symposium participants) and technical sessions covering all aspects of lake and watershed assessment and management. Supported by the New England Chapter, a limited number of Lake and Watershed Steward registration Perspectives packages are available to assist citizen stewards interested in “Autumn is a second spring when every leaf is a flower” attending Friday’s technical sessions and a workshop on —Albert Camus Saturday.

WATER COLUMN NON-PROFIT ORG. School of Public and Environmental Affairs U.S. POSTAGE Room 347 PAID 1315 E. Tenth Street Bloomington, IN Indiana University Permit No. 2 Bloomington, IN 47405-1701

CLEAN LAKES PROGRAM