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10 <br /> Proposed Conditions: <br /> 1. Prior to conducting any Teer Quarry refill operation, Falls Lake must be at or above guide curve <br /> (elevation: 251.5' mean sea level (MSL)). <br /> 2. Eno River withdrawals for transferring water to the Teer Quarry are subject to the following <br /> conditions: <br /> a. Withdrawal rate of up to 5 mgd (7.7 cfs) is currently allowable under the Voluntary Eno <br /> River Capacity Use Area (CUA) Water Management Plan,when flows in the Eno River are at <br /> or above 30 cfs from March through May and above 10 cfs during all other times of the year. <br /> River flows downstream of the Eno River intake must remain at or above 30 cfs and 10 cfs <br /> for withdrawal to occur.This is also described in the 2010 FONSI issued by the DWR allowing <br /> withdrawals for water supply from the Teer Quarry on an emergency basis; Stage 4 Water <br /> Supply Emergency.Additionally,the City of Durham has provided a chart(attached) <br /> describing the predicted withdrawal rates based upon the conceptual design constraints of <br /> the proposed weir along the southern bank of the Eno River.The pumps will be located <br /> behind the weir;therefore,water must be at a certain stage (i.e., height)to effectively flow <br /> over the structure and reach the pumps. It has been estimated by Hazen and Sawyer, <br /> consultants with the City of Durham,that the flow rates in the Eno River will meet or exceed <br /> the minimum required flows for withdrawal prior to water passing over the weir. <br /> b. Withdrawal rates exceeding 5 mgd will require a flowby rate downstream of the point of <br /> withdrawal of 49 cfs (annual median) measured at the USGS Eno River gage at Durham <br /> (US501). <br /> c. The total flowby requirement in the Eno River downstream of the point of withdrawal will <br /> be 90%of flow above 49 cfs when the Teer Quarry is above 254' MSL. <br /> d. The total flowby requirement in the Eno River downstream of the point of withdrawal will <br /> be 80%of flow above 49 cfs when the Teer Quarry is below 254' MSL. <br /> e. It is understood that unless agreements are secured with the primary partners(i.e,,water <br /> users group)of the Eno River CUA,withdrawals from the Eno River will be limited to a <br /> maximum daily withdrawal of 21.5 mgd (33.2 cfs)as outlined in "Outside Sources"section of <br /> the Eno River CUA Water Management Plan.This allowance is based upon the 16.5 mgd <br /> (25.5 cfs) allocation from Jordan Lake,which the City of Durham has been allocated by the <br /> Environmental Management Commission (EMC) and the existing 5 mgd allowance discussed <br /> in bullet 2a. <br /> 3. Lake Michie withdrawals for transferring water to Teer Quarry are subject to the following <br /> conditions: <br /> a. 3-tiered minimum release schedule for the Flat River below Lake Michie Dam: <br /> i. >70%storage = 1.75 cfs <br /> ii. 40%<_storage<70% =1.2 cfs <br /> iii. <40%storage =0.61 cfs <br /> b. No transfer of water to Teer Quarry will occur until Flat River flows below Lake Michie are at <br /> or above 11.75 cfs, measured at a gage location,yet to be determined, immediately <br /> downstream of the dam. <br /> c. The maximum rate of transfer from Lake Michie to Teer Quarry will be 20 mgd (30,9 cfs). <br /> 2 <br />