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5.3. SR 07-14-2003Item ~ 5.3. TO: FROM: DATE: SUBJECT: MEMORANDUM Mayor and City Council Stephen Rohlf ~ July 14, 2003 Mosquito Control In this memo staff will attempt to summarize the potential options for mosquito control. Attached is a staff memo from June 4, 2001 that goes into more detail. The following are the two strategies for conducting mosquito control: Killing Mosquitoes in the Larval Stage Apparently, the most effective form of control is to kill them in their larval stage. The Metropolitan Mosquito Control District concentrates about ninety percent of their efforts toward this strategy. A bacterium called Bacillus thurmgiensis subspecies israelensis (BTI) is the biological control of choice. BTI is attached to ground up corncobs and applied to wedands. The mosquito larvae ingest the material, which then creates a protein that crystallizes making it indigestible, thus killing them. Although not without environmental concern, BTI is apparendy the safest product on the market, being very specific to mosquitoes, gnats and black flies and not other wildlife. The downside to applying this product to the wedands in Elk River is cost. In 2001, the city received an estimate from a private firm of $200,000 per application to spray a conservatively estimated 4,000 acres of wedands within the city limits. To be effective, two applications are needed per year for a total of $400,000 (2001 prices). The only practical way of reaching many of the wetlands is by helicopter, which accounts for much of the cost. Contracting with the Metropolitan Mosquito Control District versus using a private firm would reduce this cost, but Sherburne County would have to petition to join the District and it would take spec/al legislation. At the Councils direction, staff approached Sherburne County regarding this issue on June 5, 2001. The county declined to pursue this issue due to cost. Spraying for adults This strategy is less effective and staff has more concerns regarding its effects on the environment and human health. The Metropolitan Mosquito Control District uses pyrethrin when spraying for adult mosquitoes, which is a botanical derivative of chrysanthemums. It is a nonspecific insecticide, meaning it can harm beneficial insects and other wildlife. There is a required setback from water bodies containing fish and the use of this product. This spray can also cause a reaction in people with allergies. Staff received one phone call this spring from a lady claiming that her and her husband got very ill from the effects of spraying and were moving to Elk River to get out of the Metropolitan Mosquito Control District. Staff did get quotes from private firms for spraying the approximately 125 miles of roads in Elk River eight times during the summer. The lowest quote was approximately $33,000. The problem with the strategy of spraying for adults is that the effects are very temporary. Although the mosquitoes that come into contact with the spray are killed, its real benefit is that it acts as a barrier or mosquito repellant. A medium strength wind can nullify this benefit. Individual Mosquito Control With the above normal amount of rainfall this year, my family and I have also struggled with the issue of mosquitoes. Private citizens can use loggers, which will act as a temporary barrier for special events. These are an insecticide and staff cautions that the directions for application should be followed very closely. Private individuals may also purchase BTI and treat their own ponds. The cost of applying BTI is excessive, but the product itself is not overly high priced. A new product is showing promise. It is a machine that uses propane to emit carbon dioxide, which is what attracts the mosquitoes to humans. The mosquitoes are then trapped in the device. Apparendy this machine has an impressive range. However, the down side is that it is somewhat expensive. The last line of defense is using bug spray containing DEET and wearing light colored loose fitting clothing. Even if some form of mosquito control is implemented in Elk River, these remedies will still be necessary to tolerate being outside during the peak of the mosquito season. Staff awaits clirecdon from the Council on this issue. PAver 13065 Orono Parkway Elk River, MN 55330 TO: FROM: Item t 4.6. MEMORANDUM MAYOR AND CITY COUNCIL STEPHEN ROHLF, BUILDING & ZONING ADMINISTRATOR 5~_.. DATE: JUNE 4, 2001 SUBJECT: MOSQUITO CONTROL METROPOLITAN MOSQUITO CONTROL DISTRICT Staff had a lengthy conversation with Mike McLean of the Metropolitan Mosquito Control District and gathered the following information: About the District The Metropolitan Mosquito Control District is a special taxing district authorized by the Legislature. The District is controlled by a seventeen member commission who are County Commissioners from the seven metropolitan counties. Anoka, Dakota, Hem~epin, and Ramsey Counties all have three members on the Commission; Washington and Scott Counties have two members each and Carver County has one. How the District Operates Ninety percent of the Mosquito Control District's efforts are aimed at killing the mosquitoes in the larval stage of their life cycle. This has proven to be the most cost effective technique. The District will do adult mosquito control on request where there is a community benefit, such as a Fourth of July celebration, but the effects of this type of control are very short lived. The District begins their efforts inside the core metropolitan area and work their way out. However, they do give a priority rating to outlying areas of high population. For example, because of their population the cities of Rogers, Andover and Ramsey are considered priority one areas. Dayton and Oak Grove Township are priority two areas. The core of Elk River would certainly be considered a priority one area, but the outlying rural area of Elk River would probably be a priority two area. Environmental Effects The District sprays wetland areas with BTI attached to ground up corncobs to kill mosquitoes in their larval stage. Areas greater than tkree acres in size are sprayed by helicopter. BTI is a biological control. The larva ingest this bacteria, which produces a protein that crystallizes inside them, they can't digest it and they die. This bacterium is very specific to mosquitoes and is therefore safe to other life forms. Years ago, things like fuel oil were used to suffocate the mosquito larva. Obviously this would not be an environmentally sound method to use. The Metropolitan Mosquito Phone: 763.441.7420 Fax: 763.441.7425 www. ci.elk-Nver, mn.us Control District does not use any methods that suffocates the larva, because it would have non-targeted effects and kill other aquatic life forms. The District uses pyrethrin when spraying for adult mosquitoes. This is a botanical chemical derived from clu'ysanthemums. Although it is a nonspecific insecticide, it has a iow toxicity to mammals. This insecticide is the active ingedient in head lice medication and flea and tick collars. The District uses it as a mosquito barrier. It not only kills the mosquitoes that come into direct 'dontact with it, but it also acts as a mosquito repellant. The down side with pyretlu'in is that, being derived from a flower, it may cause a reaction in people with allergies. The goal of mosquito control is to reduce them to a tolerable level. A complete eradication of mosquitoes would have a negative effect on the creatures that feed on them. How to Become Part of the Mosquito Control District Apparently only counties can become members of the Metropolitan Mosquito Control District. Sherbume County would have to petition to become part of the District. I! probably makes sense for Elk River to be part of the District only if Sherburne County joins anyway. Mosquitoes are carried by the wind, which in the summer are prevailingly from the west. About ten years ago, part of Sherburne County was sprayed to keep our mosquitoes from migrating into Anoka County. Since the special taxing district for mosquito control was authorized by the Legislature, it may also take special legislation for Sherburne County to join. Dallas Bohnsack, Scott County Commissioner and Chair,,of the Metropolitan Mosquito Control Commission, should be contacted for more details. Timing In staff, s opinion, it is too late to become part of the Metropolitan Mosquito Control District this summer. Their budget and manpower for the season has already been set and we have missed out on killing the first wave of mosquitoes. If it does take special legislation for Sherburne County to join the District, that process should be started immediately for next summer's control. Cost If Sherburne County joins the Metropolitan Mosquito Control District, it will have to levy a special assessment to pay for this service. The current cost is approximately $4.50 per year for a house with a valuation of $120,000. Staff estimates that the total cost for Elk River residents to be part of the District would be $25,000 to $35,000 per year. PRIVATE MOSQUITO CONTROL Staff researched the possibility of hiring a private firm to do mosquito control, staff contacted Paul Moore of Moore's Ag. Center, located in Blue Earth, Minnesota, and Dana Dunklau of Clark Mosquito Control. Both companies mainly spray to control adult mosquitoes. They both use Anvil, a pyrethriod product, which is a synthetic form of pyretherin. Both estimate that the city will need to be sprayed once a week to be effective, typically from June 1 s~ to around the first part of August. Both use a dosage of pesticide that is effective for mosquitoes, gnats and biting flies, but does not affect butterflies or fireflies. Moore's roughly charge $.40/person/application and every third application is free... Assuming the entire city was sprayed and a population of 18,000, each application would cost $7,200. With every third application being free, the average cost per application would be $4,800. Staffhas a hunch that this price may need to be adjusted due to Elk River's large land base. Moore's will also apply a BTI product to wetlands to kill the mosquitoes in their larval stage, if the city wishes. Moore's rent a helicopter to do this. Dana Dunklau of Clark Mosquito Control, charges $40/mile of road to spray for adult mosquitoes. Elk River has appro.ximately 100 miles of city streets alone. However, only roads running perpendicular to the wind (approximately half of them) are sprayed. The insecticide is allowed to drift with the wind between roads. Using 50 miles of road as an estimate, Clark mosquito control will charge approximately $2,000 for spraying just city streets. At least another $1,000 would need to be added for spraying along county roads within the city limits. Large areas of Elk River would not receive the insecticide, because of the great distance between roads in the rural areas. Staff hopes to have more exact estimates for these services to present to the Council by Monday night's meeting. CITY MOSQUITO CONTROL Another option the Council may wish to consider is buying mosquito control equipment and having city employees apply the insecticide. The equipment could be used to supplement the efforts of the Metropolitan Mosquito Control District, if Sherburne County joins in the future. The Department of Agriculture gave staff a list of three companies that deal in Ultra Low Volume (UVL) mosquito control equipment: London Fog, Clark Mosquito Control and VanWaters and Rogers. Staff contacted London Fog, which is based out of Long Lake, Minnesota. They sell three units that basically differ only in how fast the insecticide can be applied. The Metropolitan Mosquito Control District uses similar equipment. The three units are: The Model 1820 - 18 horse motor - unit mounted on skid for placement in the back of a pick-up - remote controls for operation from the pick-up cab - insecticide can be applied moving at 20 mph. - $9,455. The XKE - 8 horse motor - mounted on skids - remote control - 10 mph. application rate - $7,445. The MAG - 3 ½ horse motor - works well from a four-wheeler for doing parks or ball fields - speed 2 to 5 mph - $2,695. Clark Mosquito Control has a unit similar to the Model 1820 called a Grizzly. The applicator is self-adjusting according to your speed, the top end of which is approximately 22 mph., and it can be remotely controlled in the cab of a pick-up. However, the Grizzly is $5,000 v.~ersus the $9,455 that the Model 1820 costs. The three companies referenced also sell the insecticide. Mike Debelak from London Fog recommended Ready To Use (RTU), which is four percent permetln'in, a brand of synthetic pyrethrin. This product is specifically aimed at mosquitoes and biting flies, but staff would need to research it further before the city would actually use it. RTU costs $35/gallon. One ounce is applied per acre. Assuming Elk River's entire forty-four square miles was sprayed, 220 gallons will be needed. Spraying every last acre of Elk River would be physically impossible without a helicopter and probably not necessary. Spraying along roadsides, as proposed by Dana Dunklau, would probably be sufficient. Staff estimates the cost of the pesticide and staff time for spraying from -roads at $500 per application. Again, to be effective the city would need to spray approximately once a week from June 1st to the first of August. BTI briquettes are also available to spread in wetlands to kill the mosquitoes in their larval stage. These briquettes cost $74.50 per one hundred. Each briquette covers 100 square feet of wetland. These may be useful for wetlands in highly populated areas of the city, but would be impractical to use citywide due to the number and size of our wetlands. DEPARTMENT OF AGRICULTURE MOSQUITO CONTROL APPLICATION Staff has been in contact with Doree Maser of the Minnesota Department of Agriculture. Whether the city is included in the Metropolitan Mosquito Control District, contracts for mosquito control or chooses to conduct its own mosquito control (even just for one summer festival), a Mosquito Control Application has to be approved by the Minnesota Department of Agriculture. Staff has this application and Ms. Maser indicated that there is a fairly fast turn around on it. However, decisions on whether or not to do some sort of mosquito control this year will need to be made fairly soon. If the city chooses to do its own mosquito control, it does not need to have a commercial applicators license. SUMMARY Staff's main concerns regarding the issue of mosquito control were: environmental effects, effectiveness and cost. After researching the topic, these concerns have been mostly alleviated. The Metropolitan Mosquito Control District concentrates on killing the mosquito in the larval stage, which is the most e~xvironmentally safe and longest lasting method. However, supplemental spraying for adult mosquitoes beyond what the District does may still be desirable. Staff cautions the Council that the prices for mosquito control listed in this memo were meant only to give rough estimates of the dollars involved for this service. The methods used to figure these prices were mixed (acres, population and miles of road). RECCOMENDATIONS Staff recommends that the City Council encourage the Sherburne County Board to explore the possibility of joining the Metropolitan Mosquito Control District for next year and get a firm idea of the cost involved. Staff recommends the city get apples to apples quotes from at least Moore's Ag. Center and Dana Dunklau of Clark Mosquito Control for spraying the city for adult mosquitoes. Staff recommends the city look into the cost of doing its ovm mosquito control with its own equipment (including employee time). Staff strongly recommends that, if the city chooses to do its own mosquito control, a firm policy is developed regarding how often and where we spray. Hopefully staff will have actual quotes for the Council at Monday night's meeting. I would also like to personally thank the Council for yet another odd assignment. Contacts Metropolitan Mosquito Control District Moores Ag. Center Clark Mosquito Control London Fog VanWaters & Rogers Minnesota Department of Agriculture Website for Mosquito Control Chemicals Mike McLean (651 ) 645-9149 Paul Moore (507) 526-7333 Cell Phone (500) 370-0399 Dana Dunklau (815) 353-1774 Mike Debelak (800) 448-8525 Ed Mehan (800) 284-6264 Doree Maser (651)296-1348 www.kellysolutions.com