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Thurston County Noxious Weed Control Agreement #G0900221 1 FINAL PROJECT REPORT FOR Agreement Number: G0900221 Chehalis River Egeria densa Control Prepared by: Thurston County Noxious Weed Control Board October 22, 2010 Total Cost of Project: $79,617.00 Grant or Loan Amount: $51,937.00 Project Start Date: April 22, 2009 End Date: October 6, 2010 __________10/22/2010 &/or (AUTHORIZED SIGNATORY) DATE (PROJECT MANAGER) DATE ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 2 PROJECT SUMMARY BACKGROUND Brazilian elodea was found in Thurston County in July of 1999 approximately 7 river miles from the first discovery near Plummer Lake in Lewis County. These infestations of Brazilian elodea were hand pulled and sites marked for follow up monitoring Years 2000 and 2001, additional hand pulling efforts were made in Thurston County. In 2002, a private diver was hired to assist with removing these infestations. Even with these additional efforts more sites were being found each year. In September 2003, an increase in the removal effort was necessary to address the rate of spread of Brazilian elodea in the river. In October 2003, a survey of Brazilian elodea infestations was conducted near the source to the heaviest infestations in Lewis County to the project site in Thurston County. Scattered plants and patches were found throughout the main stem of the Chehalis River from point of original around River mile 67 to the Thurston County infestations at River mile 59. In 2004, Washington Department of Natural Resources agreed to sponsor a pilot project which used (diver dredging) to remove elodea from the Chehalis River in Thurston County. A pilot project using diver dredging to remove Brazilian elodea from the most seriously infested sites was performed from July 19, 2004 through July 29, 2004. Over seven thousand pounds of elodea was removed. Unfortunately much of this biomass returned the following years as no guidance on root removal was available at the time. In 2005, a follow up survey indicated many of the areas where biomass was removed did have significant re-growth. An expert from Portland State University was contacted for analysis and advice. Toni Pennington an ANS Research Assistant for the Environmental Science and Resources Center for Lakes & Reservoirs at PSU was consulted. Ms. Pennington observed the meticulous root removal process in 2005, her recommendations were: o Root removal must occur below the double node of the fibrous root ball for control to be achieved. This information was not available until August 2005. The 2005 project included the meticulous removal of all roots in an area of infestation in Lewis County. 1.5-2 acres of elodea was removed, 90%+ of the biomass and roots were removed in this area. No elodea has returned for nearly 5 consecutive years, in 2010 this area is free of Brazilian elodea. During 2006 through 2010, removal in the main stem of the Chehalis River included continuing this technique of removing the roots to the point of the double node. Also in 2006; o A Memorandum of Understanding for the Chehalis River Cooperative Weed Management Area was complete. o A Memorandum of Understanding between the Confederated Tribes and the Thurston County Noxious Weed Control Board was in effect 2006-2010. o A plan for the Chehalis River Weed Management Area was completed and accepted. In 2007 through 2009, Thurston County Noxious Weed Control and the Confederated Tribes of the Chehalis both receive funding from several sources; the Department of Ecology, Washington State ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 3 Salmon Recovery Board through the Nature Conservancy’s project to enhance salmon bearing streams of the Chehalis River and U.S. Fish and Wildlife and Washington State Department of Natural Resources. In 2010 Thurston County continued removal and expanded the scope of that project to 33 miles. OBJECTIVE: The objective of this project was to complete biomass removal in the un-harvested areas of the Chehalis River and to expand the survey area to River mile 33. PROJECT OVERVIEW: The Elodea Removal project began in 2009 with the purchase of supplies and equipment necessary to outfit a small pontoon boat for diver dredge operations. A photograph of the pontoon boat, and smaller dredge removal system is shown to the right. The smaller equipment was necessary due very limited access in many of the Brazilian elodea infested areas that remained after the original biomass removal projects that were performed 2005 through 2008. The earlier projects equipment could only be used in areas with good access and in slower deeper sections of the Chehalis River which occur near Fort Borst Park in Lewis County and Prather Road in Thurston County. At Prather a crane was used to lower the larger equipment into and out of the river in 2006, 07, and 08. These areas are now nearly free of Brazilian elodea. In addition to a smaller pontoon boat, a Suzuki motor was purchased by U.S. Fish and Wildlife Services and Thurston County purchased a smaller dredge system that is easily transported from site to site. With these changes in the size of equipment we were able to access all the areas that Brazilian elodea infested. Access points are 7-10 miles apart in the project area so this was an important hurdle to clear to be able to provide full removal of Egeria in all areas of the infestation. In July 2009 Washington State Fish and Wildlife provided a survey via air boat to assess safety of working in areas previously not surveyed. Three major log jams were found and locations recorded. This information was critical in keeping the dive team safe when working in very remote areas where access is difficult. The log jams are located from the confluence of Black and the Chehalis Rivers about 2 miles. ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 4 A new GPS trimble unit was purchased to accurately locate scattered plants throughout the infested areas. A pre removal survey was conducted in 2009 and 2010. A map was created for the dive team to follow on a day by day basis for planning each day’s work. During 2009 18 miles of the main stem were cleared of all known Brazilian elodea. This was the first time all known locations of Brazilian elodea had been removed in a single season. During 2010 34 miles of the main stem were cleared of all known Brazilian elodea, making the second consecutive season for total removal of the infestation. The Chehalis Tribe had similar equipment and staff the first year of this project. The following is a report from the Chehalis Tribe Biologist in 2009: The Chehalis Tribe’s Noxious Weed Program was able to remove a great deal of Brazilian Elodea during the 2009 season. They began their work with surveys to determine the extent of the Elodea and where would be the best locations to use the two different dredges that the Program owns. The surveys went from Fort Borst Park in Centralia to the mouth of the Satsop River near Keys RD in Grays Harbor County. They were happy to discover that the Elodea seems to be losing its battle against the weed warriors that have been battling it for the last several years. They anticipated there being more to remove and that there would be more concentrated areas of infestation; what they found was the opposite. There were few concentrated areas and what was left was often single or double plants tucked inside native elodea patches as well as other native aquatic plants. This required different strategies and meant that the Program’s smaller more portable dredge would become essential to eliminate the scattered sparse plants more effectively. They were still able to use the barge mounted dredge in several locations--mainly focused on the areas just above the mouth of Independence Creek in a very large slough. Even with the scattered plants and few locations to utilize the larger dredge the crews were able to pull and remove 11,693 lbs of Brazilian Elodea. We are happy to say that there just wasn’t anymore to pull in the survey area that the Program focused on. They were happy to be able to work closer to home and be able to remove any of the infestations that were located on the Chehalis Reservation. The Program and its work will continue next year and will probably consist of using the portable dredge and surveying to locate and remove any last ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 5 remaining infestations or new plants that might have been dislodged from Plummer Lake or any of the many sloughs that routinely flood and wash their contents into the Chehalis River. The following is the 2010 overview by the barge tender for this project Dan Reynoldson: Borst Park to Galvin: Most of the elodea was found in this stretch of the river along the north bank about 1/4 mile from the boat launch to the first riffle. About 1875 pounds were found on the north bank and another 30 pounds on the south bank. At the slough just upstream of the Galvin Bridge we found about another 1190 pounds. Galvin Bridge to Prather Road: We found about 210 pounds along west bank from bridge to Busek's riffle. Lincoln Creek inlet: 230 pounds was removed at the Lincoln Creek inlet. There was no Brazilian elodea on the main stem to Prather Road Bridge. Prather Road Bridge to Independence: About 48 pounds was removed at Doleman's farm or the Maple Lane outfall. Upstream from Scatter Creek: 930 pounds was removed, mostly on the north bank upstream from Scatter Creek. This volume is much reduced from 2009. Independence to Black River: Only 3 pounds were removed, mostly just below the Independence launch. Black River to Oakville: Only 3 plants were found. We then entered into never-before-surveyed areas Oakville to Porter: About 460 pounds of elodea was found in a side slough, just below the Oakville boat launch on the south bank. About 540 pounds found in a back slough about halfway to Porter on the south bank. The main stem of the Chehalis River was clean. Only two areas did not show improvement from 2009. The area just from the Borst Park boat launch was about the same as last year. Galvin main stem was worse. All other areas were better than in the past except the new areas of Black River Largest infestation near Fort Borst boat launch 2010 ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 6 PLANT SURVEYS AND MAPS ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 7 ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 8 ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 9 Control methods: Diver dredging (suction dredging) was be used in the Chehalis River main stem, staffing requires three divers, one who is also a barge tender. Diver dredging is a method where divers use hoses attached to small dredges to vacuum plant material out of the river, after dislodging the roots. The purpose of diver dredging is to effectively remove all of the plant biomass including the roots. The divers use the suction hose to dispose of Brazilian elodea only. The water is returned back to the water column and the plant material is retained. The technique is consistent with the existing hydraulic permit for removing noxious weeds permitted by the Washington State Department of Fish and Wildlife. Diver dredging is effective against Brazilian elodea because the plant and root structures can be removed entirely from the aquatic system. This technique has been used on Brazilian elodea in the Chehalis River since 2005. ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 10 lbs of Brazilian elodea removed 7740 44910 76708 106772 47425 25963 5519 315037 0 50000 100000 150000 200000 250000 300000 [PHONE REDACTED] 2005 2006 2007 2008 2009 2010 total amount remove Acres of elodea removed 1.5 5.41 9.449.92 8.03 6.22 0 2 4 6 8 10 12 2005 2006 2007 2008 2009 2010 Monitoring: Efficacy is determined by the amount of area and biomass removed from the project area annually and comparing it to the previous years’ total, and the # of river miles surveyed. WATER QUALITY BENEFITS: In 2007 oxygen levels were measured in areas with large mats of Brazilian elodea, prior to removal. That first reading was compared to a reading taken after removal was complete. The results of the two comparisons demonstrated a 7.75% increase in dissolved oxygen after Brazilian elodea was removed from the Chehalis River. An additional attempt to measure oxygen levels was attempted in 2009 at the Lincoln Creek slough area. No conclusions were able to be made from this attempt at measuring before and after DO readings. Populations of Brazilian elodea have now been reduced to the point where readings will most likely not show any differentiation as no large canopied mats now occur anywhere in the area of the infestation. In 2009 and 2010 only small patches very near the shoreline and mostly individual plants are what we are removing. This probably does not alter DO levels. River miles surveyed 7 7 13 18 20 22 34 0 5 10 15 20 25 30 35 40 2004 2005 2006 2007 2008 2009 2010 ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 11 EDUCATION/COMMUNICATION COMPONENTS Education: A news release was written and resulted in several papers covering the progress with elodea on the Chehalis River in 2009. Several articles are pasted as they appear in local papers: Each year the Brazilian elodea project brochure is updated and posted on our web site. ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 12 ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 13 OVERALL PROJECT RESULTS: According to the statistics tracked, bio mass removal in 2009 had decreased 54% from 2008 and in 2010 78.8% from 2009 levels. In terms of acreage removed 38% less elodea was removed in 2010 from the high of 9.92 acres in 2008. PROPOSED MANAGEMENT FOR FUTURE YEARS: Additional funding is being applied for to continue to mop up the remaining Brazilian elodea in the main stem of the Chehalis River. If progress continues at this pace it may be realistic to establish an eradication goal in the future. 2006 2010 Budget Summary: Brazilian Elodea Project Hours DOE 2009 Hours 2010 Hours Chehalis River main stem-Prather Road ---PAGE BREAK--- Thurston County Noxious Weed Control Agreement #G0900221 14 Rick Johnson 69 20 Angela Celestine 3.5 Dan Reynoldson 203 125 Dive Team 426 231 US F&W Rick Johnson 22 32.00 Dan Reynoldson 124 50.00 Dive Team 208 139.25 Subtotal 1055.5 597.25 Total Hours of Project 1652.75 Description 2009 Costs Reimbursements DOE $35,928.39 $35,928.40 US F&W $14,312.59 $14,312.59 2009 TOTAL $50,240.98 $50,240.99 Description 2010 Costs Reimbursements US F&W $9,454.99 $9,454.99 DOE $19,921.22 $16,008.61 Total Project costs Total Project Reimbursements 2009 TOTAL COSTS $50,240.98 $50,240.99 2010 TOTAL COSTS $29,376.21 $25,463.60 TOTAL PROJECT COSTS $79,617.19 $75,704.59