Minutes 11-10-2015 - Laserfiche WebLink

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http://www.ncwater.org/Data and Modeling/Ground Water Databases Staff plans to begin an outreach campaign on groundwater information for County residents in late 2015-early 2016. Informational outreach materials are being designed that will help residents learn a variety of useful information, from basic hydrologic concepts to measures for planning the installation of supply wells which may help increase the yield of water from these wells (please see Attachments C and D). These documents will be used in combination with data gathered from the OWN network to inform residents of common facts about hydrogeology, especially with regard to groundwater occurrence and usage. 6. Eno River Hydrilla Management Pilot Study Update Tom Davis reviewed the following information: BACKGROUND: Hydrilla (Hydrilla verticillata) is an invasive aquatic plant native to Asia that was first noted in the United States in the 1960s (Attachment A). Since then, hydrilla has spread rapidly in the U.S., reaching nuisance levels in many locations. Hydrilla has been called "the perfect aquatic plant" because it spreads rapidly, is able to reproduce in four different ways, grows in extremely low light, and is able to crowd out native aquatic vegetation. For many years hydrilla has been present in portions of the Eno watershed, including Lake Orange, Corporation Lake, and the West Fork of the Eno Reservoir. More recently, Eno River State Park staff noted that hydrilla is their "number one resource management problem in the Eno". Hydrilla causes negative water quality impacts, can be harmful to the river ecosystem, and adversely impacts the recreational experiences of people visiting the State Park and elsewhere. Hydrilla can be spread from one water body to another via watercraft or waterfowl. The plant can also be spread by people discarding aquarium materials into waterways. In 2011 the Eno River Hydrilla Management Task Force, comprised of local governments and state agencies, including the Aquatic Weed Program of the NC Division of Water Resources, began planning to address the hydrilla infestation in the Eno River. The Task Force agreed to conduct a two-year pilot study to examine the effectiveness of using a US Environmental Protection Agency-approved herbicide to manage hydrilla in a portion of the river. In April 2015 the Task Force hosted a public information open house in Hillsborough concerning the pilot study (Attachment B). Details were provided on the problem, the results of an Environmental Assessment for the proposed project, and the selection of a contractor to apply and monitor the herbicide in the Eno. Additional public outreach efforts were conducted throughout the watershed (Attachment C). Pilot study herbicide treatments in the Eno River began in late May 2015. Low stream flows over the summer aided in maintaining a consistent concentration of fluridone, the active ingredient in the herbicide, throughout the treatment zone, from Lawrence Road east of Hillsborough downstream to Roxboro Road in Durham. Monitoring of the concentration of fluridone in various locations along the river occurred throughout the duration of the study. Monitoring of native vegetation, snails, crayfish and fish above and within the treatment zone was also conducted before and during the hydrilla treatment. Bleaching of hydrilla was observed after just one week of herbicide treatments. Within four weeks, there was notable reduction in the density of hydrilla in the treatment zone. Further herbicide treatment resulted in dramatic differences in hydrilla density between the treatment area and the untreated area upstream. Nearly-complete removal of visible hydrilla vegetation was reported at locations within the area of treatment.