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2 <br /> 1. Lake and Watershed Water Quality Monitoring <br /> CardnoEntrix, the consultant working for the UNRBA, completed the first 12 months of water <br /> quality sampling in July 2015. The Falls Lake Rules stipulate that in order for outside data to be <br /> evaluated during the re-examination of Stage II of the Falls Lake Rules, a minimum of three <br /> years of sampling data must be collected for the data to be considered by the Environmental <br /> Management Commission (EMC). The UNRBA's water quality sampling program is producing <br /> information for the following purposes: <br /> ♦ Determination of sources of nutrients in the watershed and the loading of nutrients <br /> from individual jurisdictions to Falls Lake; <br /> ♦ Falls Lake response modeling; <br /> ♦ Development of data for consideration of additional regulatory options; and <br /> ♦ Linkage of water quality conditions in Falls Lake to the designated uses of the <br /> Lake. <br /> Attachment A identifies the locations of surface water sampling stations for both the <br /> jurisdictional and lake tributary nutrient loading determination projects. All of the data collected <br /> is available for review at the web site set up for this purpose: http:ffunrba-wgp.cardno.com/ <br /> Attachment C is an example of the results obtained from water quality samples collected in five <br /> streams that feed into the northern end of Falls Lake. Fairly significant variations in these <br /> nutrient concentrations are seen among the five streams, as well as over the course of the time <br /> interval shown for two of the streams listed. Attachment D illustrates variations in the volume of <br /> stream flow in three streams in the upper portion of the Falls Lake watershed. The combination <br /> of nutrient concentration and rate of streamflow in each individual stream determines the <br /> amount (loading) of nutrients entering Falls Lake, so a stream that contains a low concentration <br /> of nutrients (such as Eno River) could actually contribute more nutrient loading if its streamflow <br /> was significantly larger than a second stream with a higher concentration of nutrients (such as <br /> Ellerbe Creek). <br /> CardnoEntrix is also collecting data for the following Special Studies as part of the Falls Rules <br /> re-examination process: <br /> ♦ Falls Lake Constriction Point Monitoring <br /> ♦ High Flow Monitoring <br /> ♦ Storm Event Sampling <br /> ♦ Sediment Sample Analysis <br /> ♦ Light Penetration Analysis <br /> ♦ Volatile Suspended Sediment Determination <br /> ♦ Survey of Recreational Use of Falls Lake <br /> ♦ Model Performance Evaluation <br /> ♦ Evaluation of Regulatory Options to Falls Lake Rules <br /> 2. BMP Nutrient Credit Development <br /> CardnoEntrix is continuing to work on a project to develop nutrient reduction Best Management <br /> Practice (BMP) credits. The project will be beneficial to UNRBA member governments <br /> (including Orange County) by increasing the number of structural devices and other stormwater <br /> practices with known nutrient reduction values. These BMPs will then be available for affected <br /> parties to use to meet the required nutrient reduction goals under Stages I and 11 of the Falls <br />