Professional Engineers Of North Carolina

SUM 2014

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Page 17 of 31

16 the Professional Engineer Summer 2014 Haw River Arm • TN – 8% reduction from the 1997 to 2001 baseline load of 2,790,217 pounds per year allocated approximately 35 percent to point sources and 65 percent to nonpoint sources. • TP – 5% reduction from the 1997 to 2001 baseline load of 378,569 pounds per year allocated approximately 29% to point sources and 71% to nonpoint sources. The adopted rules were quite comprehensive and included the following components: • Stormwater Rules — New Development • Stormwater Rules — Existing Development • Riparian Buffer Rules • Wastewater Discharge Rule • Agricultural Rule • Fertilizer Management Rule • Options for Offsetting Nutrient Loads General Assembly actions Signifcant portions of these rules were subsequently either modifed or completely disapproved by the General Assembly. Te Nutrient Strategy Purpose and Scope (including the reduction goals listed above), Agricultural Rule, Fertilizer Management Rule and Options for Ofsetting Nutrient Loads were not modifed by the General Assembly. Stormwater Rules for Existing Development were repealed and all other rules were modifed to some extent by legislative action in 2009, 2011, 2012 and 2013, efectively delaying implementation of portions of the rules. Tese legislative actions occurred under the leadership of each of the major parties. Te 2013 legislation efectively delayed aspects of the Jordan Lake Rules while a lake circulation technology known as "Solar- Bees" are tested. DENR is moving forward with installation and testing of this technology potentially beginning in 2014. Observations Te media and many community and environmental groups have publically derided the delays by the legislature in implementation of the "Jordan Lake Rules". Several timelines related to the lake have been published with proponents of the rules concluding that delay in eforts to reduce nutrients and prevent further increases should not be tolerated. While this is an understandable perspective, the Jordan Lake situation is unusual and the following observations are ofered. • Despite the nutrient response modeling analysis completed in 2002 based on data from 1997 to 2001, there is little evidence that reductions in nutrients will substantially change the conditions in the lake. Te lake was predicted to be eutrophic before impoundment, and monitoring over the last 30 years has continued to prove this to be the case. As pointed out in the history above, there was little concern about the lake quality between 1984 and 2002 until the modeling (prompted by legislative requirements not specifcally aimed at Jordan Lake) and additional data collected to support the model development indicated the lake was impaired based upon chlorophyll a data. Tere is no question that there has been signifcant development in the lake's watershed and corresponding increases in nutrient loading over the last 30 years; however, there has not been a comprehensive assessment of data collected from 1982 to present to indicate whether the lake has become more eutrophic or is similar to the years after impoundment. Many piedmont reservoirs are eutrophic, including those in relatively protected watersheds. • Several local governments have moved forward with implementation of portions of the Jordan Lake Rules, primarily related to bufers and new CHATHAM WAKE ORANGE DURHAM Chapel Hill Durham Haw River Morgan Creek Jordan Lake Warm, lighter water SolarBee water circulator Cool, dense water Thermocline 24 units SolarBee locations 12 units 501 64 15 1 751 54 40 SolarBees only circulate water above the thermocline because the depths are full of nutrients that encourage cyanobacteria. J o r d a n L a k e

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