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drought conditions evident in more than 75 years of official rainfall /streamflow record <br />keeping. Although a critical water supply shortage was narrowly averted, the drought <br />eventually came and went without completely emptying Lake Orange and with several <br />months of water supply (sufficient to meet at least Hillsborough's demand) remaining in <br />the West Fork reservoir. <br />Insofar as the West Fork Reservoir is concerned, the Capacity Use Agreement does not <br />specify any limit on Hillsborough withdrawals from the reservoir. With the exception of the <br />requirement for an instream flow contribution, the agreement treats water from the <br />reservoir as if it were an outside the Eno basin water supply similar to Hillsborough's <br />historical purchases of treated water from OWASA or the City of Durham. <br />West Fork Reservoir <br />Construction of the Phase I reservoir (impounding approximately 786 million gallons of <br />water when filled to an elevation of approximately 633.0 feet MSL, surface area of 204 <br />acres) was essentially completed in the fall of 2000. The net fifty year safe yield of the <br />Phase I reservoir (not including releases for instream flow) has been estimated to be 1.8 <br />million gallons per day, giving the Town a total raw water availability of approximately 3.2 <br />mgd under the first stage of Eno River Capacity Use Agreement withdrawal limitations. <br />Note: the term "50 -year safe yield" represents a statistical projection or extrapolation that essentially means that, at a daily <br />draft of 1.8 million gallons, there is a 100% probability that the reservoir will be completely depleted once in a 50 year period <br />and /or a 2% probability that it will be depleted in any given year. The Town began filling the reservoir in <br />early 2001 after a resolving several problems that allowed water to leak out of the <br />reservoir through its intake /release structure. In spite of the severe drought of 2002, the <br />reservoir has been filled to capacity since December 2002. Releases from a partially filled <br />(approximately 60 %) reservoir during the summer and early fall of 2002 helped prevent <br />the total draw -down of Lake Orange during the drought of 2002 and afforded the Town a <br />reliable supply of raw water when its Eno allocation had been significantly reduced and no <br />water was available for transfer from either the City of Durham or OWASA. <br />The plethora of permitting requirements imposed on the construction /development of the <br />reservoir by permitting authorities (US Army Corps of Engineers, US and NC Fish and <br />Wildlife, NC Division of Land Quality — Dam Safety section, NC Division of Water <br />Resources) include only one condition which modifies the terms and conditions of the Eno <br />River Capacity Use Agreement. Hillsborough is required to constantly release an amount <br />of water, ranging from 4.0 cfs (2.6 mgd) to 1.0 cfs (650,000 gallons per day [gpd]) to the <br />Eno, based on the time of year and the amount of water impounded at the time of release. <br />The 4.0 cfs is measured near the outlet from the dam intake /release structure occurs <br />during the month of April if the reservoir is filled to 60 percent or more of its capacity. The <br />1.0 cfs minimum release (which includes an additional release to account for in- channel <br />loses) is measured at the Hillsboro gage irrespective of the time of year or quantity of <br />water stored in the reservoir. The Capacity Use Agreement has been modified only to <br />incorporate the minimum 1.0 cfs release. <br />draft <br />