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HomeMy WebLinkAboutAgenda - 05-02-1994 - V-C ti ' 1 O R A N G E C O U N T Y BOARD OF COMMISSIONERS ACTION AGENDA ITEM ABSTRACT Meeting Date: May 2, 1994 Action Agenda Item SUBJECT: Weed Control Resolution for Lake Orange hydrilla infestation/grass carp program cost-share with the NC Division of Water Resources DEPARTMENT: PUBLIC HEARING: Yes X No County Manager ATTACHMENT(S) : INFORMATION CONTACT: Resolution County Engineer - Ext. 2303 TELEPHONE NUMBERS: Hillsborough - 732-8181 Durham - 688-7331 Mebane - 227-2031 Chapel Hill - 967-9251/968-4501 PURPOSE: To present to the BOCC for its approval an aquatic weed control resolution which is an agreement between the NC Division of Water Resources (DWR) and Orange County whereby the County agrees to assume fifty percent of the costs of stocking Lake Orange with the grass carp necessary to control the lake's hydrilla infestation BACKGROUND: Hydrilla (Hydrilla verticillata) is a submersed aquatic plant that forms a very dense and nearly impenetrable mat of stems and leaves at and below the water surface of its habitat. Hydrilla is not native to North America, but it is now found throughout temperate and tropic areas of the United States. It was imported into North America for use as an aquarium plant in the 1950 ' s and may have been have been introduced into the environment when aquaria media were released into surface waters. Hydrilla is considered to be the most noxious fresh water aquatic weed in the southeastern United States. It is extremely hardy and prolific; it is readily spread between water bodies that are not contiguous; and it degrades the quality of aquatic wildlife habitat as well as the recreational and aesthetic attributes of an infested water body. Aquatic weed specialists theorize that hydrilla usually spreads to unifested lakes and ponds by adhering to boats, trailers, etc. or aquatic animals. Hydrilla may also be purposely introduced into a water body in a 1 2 misguided attempt to provide habitat for game fish. Aquatic week specialists generally attribute approximately ninety percent of the spread of hydrilla infestation to human activities. The first official identification of hydrilla in Lake Orange occurred in October 1992, although there is anecdotal evidence that hydrilla may have been present for ten or more years prior to that. Immediately upon their identification of hydrilla in Lake Orange, Cooperative Extension officials notified the NC Division of Water Resources (DWR) . DWR is the state agency which has responsibility for responding to hydrilla problems. Dr. David DeMont, director of the Aquatic Weed section of DWR, made a site visit to Lake Orange shortly thereafter to confirm the presence of hydrilla and to assess the severity of the infestation. By January 1993, DWR staff had completed a field survey and measurement of the hydrilla infested areas of Lake Orange. The survey indicated that approximately eighty acres (fifty percent of the normal surface area) of Lake Orange were infested with hydrilla. A North Carolina Cooperative Extension Service publication which describes the state's hydrilla problem outlines a number of methods which have been used to control hydrilla. The literature indicates that many of the traditional methods of acquatic weed control, including those which involve draining a lake and mechanically removing the weed growth, are expensive and ineffective in eliminating hydrilla. Two methods of treatment which have been successful in suppressing hydrilla are: a) periodic application of specialized aquatic herbicides; and b) stocking an infested lake with genetically sterilized (non-reproducing) grass eating carp. The herbicides are commonly used in lakes which provide water for human and livestock consumption and are considered to be non-toxic to wildlife. The primary disadvantage to aquatic herbicides is expense. Significant quantities of the herbicide must be used in each of several applications per season. The use of herbicides to provide treatment of all infested areas of Lake Orange would cost tens of thousands of dollars per year. The method of controlling hydrilla with grass carp is very economical. The carp, which seem to prefer hydrilla to other desirable acquatic weeds, consume up to three times their weight in hydrilla each day and are stocked at a rate of twenty fish per acre of infestation. The carp are approximately ten inches long and weigh less than one pound introduced into a lake. Grass carp may live up to ten years and, at maturity, can exceed thirty-six inches in length and weigh in excess of twenty pounds. Dr. DeMont has determined that the extent of the hydrilla infestation at Lake Orange requires that the lake be stocked with 1800 grass carp at total cost of approximately $8000. 3 The Division of Water Resources operates a local government cost-share program for stocking publically owned lakes which have hydrilla infestations with grass carp. Under this program, DWR will pay one-half of the cost of stocking Lake Orange with grass carp. As a condition of its cost share program, DWR requires local governments to pass a weed control ordinance which is, in actuality, a contract between a local government and the Division of Water Resources. A proposed weed control ordinance for Orange County is attached. In addition to the state cost-share funds, Lake Orange Incorporated which represents the property owners bordering the lake have agreed to pay $2000 or one-half of the County's share of the stocking cost. The resulting total cost to the County is $2000 which can be drawn from the Lake Orange account. This account is currently used to pay expenses associated with the maintenance of Lake Orange and the County's operational responsibilities in the Eno River Capacity Use Agreement. RECOMMENDATION: The Manager recommends that the BOCC pass the Aquatic Weed Control resolution and that it direct staff to expend the necessary funds from the Lake Orange account. 4 AQUATIC WEED CONTROL RESOLUTION WHEREAS, the Orange County Board of Commissioners desires technical and financial assistance from the N.C. Aquatic Weed Program for treatment and control of eighty acres of hydrilla infestation at Lake Orange, a reservoir useful for raw drinking water supply, recreation, wildlife habitat and scenic beauty, NOW, THEREFORE, BE IT RESOLVED THAT: The Board requests that the N C Aquatic Weed Program conduct the Lake Orange aquatic weed control project; The Board assumes full obligation for payment of fifty percent (50%) of non-federal costs associated with Lake Orange aquatic weed project; The Board will assist the NC Department of Environment, Health and Natural Resources and/or the US Army Corps of Engineers in quantifying its aquatic weed problems and determining the public benefits of the project; The Board will hold the State harmless from any damages that may result from the project with the exception that the State will not be held harmless from damages resulting from any negligence, incompetency or malfeasance on the part of its employees, agents or contractors; The Board will be responsible for notifying all landowners whose property is adjacent to the body of water in which the control project is located and for sponsoring any public information meetings that may be needed; and The Board will, to the extent of its power and authority, enforce any temporary restrictions on the use of the body of water as required by the specific method of treatment used. ADOPTED BY THE ORANGE COUNTY BOARD OF COMMISSIONERS this 2nd day of May, 1994 Witness: Beverly Blythe, Moses Carey, Chair - Orange Clerk to the Board of County Board of Commissioners County Commissioners