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HomeMy WebLinkAboutItem 12-3 - Information Item - Memorandum-Water Resources Information Item 1 Department of Environment, Agriculture, Park &Recreation MEMORANDUM TO: Board of Orange County Commissioners CC: Bonnie Hammersley, County Manager FROM: Dave Stancil, DEAPR Director Tom Davis, Water Resources Coordinator DATE: November 20, 2018 RE: Water Resources Information Item This memorandum includes updates for several ongoing water resource projects: 1. The Upper Neuse River Basin Association 2. Hydrilla in the Eno River 3. Former Hillsborough Landfill 4. Orange Well Net 1. The Upper Neuse River Basin Association The Upper Neuse River Basin Association (UNRBA), of which Orange County is a longtime member, is working on a multi-year effort titled "The Path Forward" to revise Stage II of the Falls Lake Nutrient Management Strategy (Falls Rules). As currently written, Stage II of the Falls Rules requires regulated parties, including local governments, located in the Falls Lake watershed to reduce nitrogen and phosphorus nutrient loading to Falls Lake by 40% and 77%, respectively. While UNRBA members agree that protecting water quality and Falls Lake as the City of Raleigh's water supply is a top priority, members also noted and assert that there were serious technical shortcomings with the process underlying the adoption of the Falls Rules in 2011, as Orange County Department of Environment, Agriculture, Parks & Recreation PO Box 8181 Hillsborough, NC 27278 Phone: (919) 245-2510 Fax: (919) 644-3351 2 well as significant financial impediments to the regulated parties tasked with meeting the Stage II nutrient reduction goals as they are currently written. The UNRBA continues to make progress on several projects related to the revision of Stage II of the Falls Lake Rules, including: • Lake and Watershed Water Quality Monitoring • Development of Nutrient Credits for Stormwater Devices • Modeling and Regulatory Support Lake and Watershed Water Quality Monitoring The UNRBA has been collecting water quality samples from the Falls Lake watershed since August 2014. This monitoring will be completed in October 2018. A much more limited sampling program will continue through the remainder of the current fiscal year. The water quality data that has been collected will be incorporated into the on-going Stage II re-examination process. An annual monitoring report was completed in May 2018 that summarizes all of the water quality data that has been collected through December 2017. This document, along with all of the data that has been collected by the UNRBA, is available at http://unrba-wgp.cardno.com/. Development of Nutrient Credits The UNRBA has developed nutrient reduction credits for several stormwater control measures (SCMs) that have been approved by the NC Division of Water Resources. Local governments can now use these additional SCMs to meet the nutrient reduction goals required by the Falls Rules. This is beneficial to UNRBA member governments because it increases the number of devices and stormwater practices or "tool box" that have DWR-approved nutrient reduction values. The UNRBA continues to negotiate with DWR concerning the approval of nutrient reduction credits for the preservation of open space within the watershed. Unfortunately, to date, DWR seems to be unwilling to provide more than a minimal credit for the preservation of open space. Modeling and Regulatory Support As part of the process for developing more reasonable Stage II nutrient reduction goals for Falls Lake, the UNRBA is beginning the remodeling of the lake and watershed, including hydrologic information and nutrient cycling and other relevant processes. This multi-year effort will incorporate the data that the UNRBA has collected into a model as a means of exploring options for meeting water quality standards in Falls Lake. The UNRBA is also beginning to work with a legal firm to evaluate the potential regulatory options that may be available for determining a more technically and fiscally reasonable Orange County Department of Environment, Agriculture, Parks & Recreation PO Box 8181 Hillsborough, NC 27278 Phone: (919) 245-2510 Fax: (919) 644-3351 3 means of achieving compliance in Falls Lake. These options could include a variance from State surface water quality standards for a portion of Falls Lake, the completion of a Use Attainability Analysis, and others. Related Issues As required by the Falls Rules, DWR plans to release their previously delayed Existing Development Model Local Program in July 2019. This document will include the following items: • An updated catalog of nutrient reduction practices including stormwater control measures and practices, • Determinations of Stage 1 nutrient loading for each local government in the watershed that results from development that occurred between 2006 and 2012, • The nutrient trading framework that must be developed before nutrient trading can take place between regulated parties in the Falls Lake watershed, as well as • Guidance that local governments can utilize to implement the existing development requirements in their jurisdictions. 2. Hydrilla in the Eno River The Eno River Hydrilla Management Task Force (Task Force) continues to address the presence of this invasive non-native aquatic plant in the Eno River. This year is the fourth consecutive year that a low concentration of an EPA-approved herbicide (fluridone) was added to the Eno to manage the presence of hydrilla. Two injector units were used the last two years to maintain a low concentration of herbicide throughout the treatment zone which extends from just below Lake Ben Johnston in Hillsborough to Roxboro Road in Durham County. No serious impacts to non-target species in the Eno River have been identified. In addition to limiting the visible growth of hydrilla, the repeated use of herbicide will continue to reduce the stock of viable hydrilla tubers in the sediment within the riverbed. Efforts are still underway to further define the extent of hydrilla within the entire Eno River watershed, including in private ponds that may be connected to the Eno River. Plans are underway for a public information open house to be held by the Task Force at the Whitted Center in early spring 2019. 3. Former Hillsborough Landfill Orange County continues to work with a contractor to assess the extent and impact of waste materials buried in the former Town of Hillsborough landfill located in the Fairview Orange County Department of Environment, Agriculture, Parks & Recreation PO Box 8181 Hillsborough, NC 27278 Phone: (919) 245-2510 Fax: (919) 644-3351 4 neighborhood. The completion of the initial set of borings intended to define the outer edge of the waste materials seems to indicate that landfill waste may not be as widespread as previously thought. Additional investigation was completed in late September that completed the delineation of the landfill waste boundary. Further site investigation, including vapor, soil and groundwater assessment, is expected to be completed in the upcoming months. To date, the County has been successful in seeking reimbursement from the Department of Environmental Quality Division of Waste Management (DWM) for the expenses that have been incurred on this project, and further work in this area will be pursued in the same manner. 4. Orange Well Net Groundwater level data continues to be collected from the seven bedrock wells and six regolith wells that are included in the Orange Well Net (OWN) groundwater observation well network. The goals of the groundwater observation well network include the collection of groundwater level data from a combination of bedrock and regolith wells spread across Orange County. Regolith wells monitor natural stresses on the quantity of groundwater available in storage caused by variations in climatic conditions. Bedrock wells monitor changes in groundwater levels in the bedrock across the county. Taken together, the Orange Well Net (OWN) is designed to collect information concerning the amount of groundwater available locally in Orange County, especially regarding drought conditions. The information that is being collected by the well network is available at the following web site: https://www.ncwater.orq/?paqe=537&tl=l&net=ora n qe&i n active=. Orange County Department of Environment, Agriculture, Parks & Recreation PO Box 8181 Hillsborough, NC 27278 Phone: (919) 245-2510 Fax: (919) 644-3351