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A summary of the Project Drainage Area(PDA) is as shown in Table 1 below: <br /> TABLE 1 -- TOTAL PROJECT DRAINAGE AREA <br /> Area <br /> Description Proposed Surface <br /> ID SF Ac <br /> Existing School Property Area <br /> New NW Parking Lot Access from 127th PL SE & New& Replaced <br /> New Entry from SR-527 Surface/Grading 'A 71,683 1.65 <br /> Restriping, Sidewalk & <br /> Curbing in West& <br /> Remaining School Property Area Excluding Area B3 South Parking Lots C 412,003 9.46 <br /> 483,686 11.10 <br /> Area Outside Lot 7 Property Lines &within School New& Replaced <br /> Property Surface/Grading B3 2,276 0.05 <br /> 485,962 11.16 <br /> Future Lot 7 Area <br /> Lot 7 To Be Acquired by EPS for Access from 129th <br /> Place SE New& Replaced B 10,131 0.23 <br /> Area Outside Lot 7 Property Lines w/in ROW New& Replaced B2 1,509 0.03 <br /> 11,640 0.27 <br /> Total Project Drainage Area (PDA) 497,602 11.42 <br /> Notes: <br /> 1. Per Area Takeoff Calculations 11/25/02 <br /> Existing Offsite and Site Discharges <br /> ❖ Offsite—Offsite flows from upstream areas to the south pass through the School <br /> Property via an existing 12-inch pipe under the playfields to the North. See Section <br /> 3 —Upstream Analysis for detailed description of these conditions. <br /> ❖ Northwest—The western half of the School Property site discharges via catch basins <br /> and sheet flow into the SR-527 conveyance system. See Section 4—Downstream <br /> Analysis <br /> ❖ Northeast—The eastern half of the School Property and Lot 7 Area discharges via <br /> catch basins,sheet flow and subdrainage to a 12-inch pipe at the north property line <br /> that extends through the Hershclip subdivision to an existing detention pond. <br /> Targeted Drainage Report for Everett Public Schools Section 2—Risk&Erosion Control <br /> Silver Lake Elementary Parking Lot Expansion January 6,2003 <br /> By: Perteet Engineering Page 3 of 7 <br />