Larry Smith, Videra Drive HOA <br />11  <br /> <br /> <br />3) Stormwater Plan Provides Insufficient Capacity <br />Eugene Code is very clear on the requirement for the proposed development to handle at least as much <br />capacity and flow control as the existing natural features on the property: <br />“9.6790 Stormwater Management Manual…. <br /> (2) Control and minimize flows from development in the Headwater Areas using a variety <br />of techniques to release water to downstream conveyance systems at a slower rate <br />and lower volume, thereby reducing the potential for further aggravation of instream <br />erosion problems.” <br />“9.6793 Stormwater Flow Control (Headwaters). <br />(3) Standards. <br />(a) Applications shall demonstrate, using methodology in the Stormwater <br />Management Manual, that peak rates of flow delivered to an existing open <br />waterway at a point above 500 feet in elevation will not increase during <br />storms larger than the water quality design storm and smaller than the <br />flood control design storm as a result of the development that is the <br />subject of the application; “ <br />The existing wetland areas on the proposed development area have a substantial water capacity and <br />provide a very effective filter with the dense organic mat present. Figure 3 shows the existing Conditions. <br />Figure 4, looking across the area referenced as “Wetland 1”, shows the high density of the vegetation. <br />The aerial views in Figure 11 show the extent of lush wetlands. Even though the images were captured on <br />October 17, 2022, after more than a month with no rain, high water retention in the wetlands is evident. <br />The wetlands discharge partly via the 12” culvert across Hawkins Lane. In Addition, there is substantial <br />subsurface/groundwater flow fed by the wetlands to the east. These flows converge with the discharge <br />from Randy Lane to form Videra Creek. <br />Table 2 shows the amount of storage capacity which is estimated for this natural stormwater <br />retention/treatment feature. Effectiveness of this natural fixture can be seen in Table 3 which compares <br />the existing capacity to the capacity provided with a new treatment facility designed according to Eugene <br />stormwater standards: <br /> <br />“9.4930 /WR Water Resources Conservation Overlay Zone - Permitted and Prohibited Uses and <br />Exceptions. Uses are permitted or prohibited within the /WR Resources Conservation Overlay <br />Zone based on whether they occur inside or outside the /WR Conservation Area as defined in EC <br />9.4920, as follows: <br /> (h) Discharge of stormwater collected from impervious surfaces into a wetland or <br />stream within the /WR conservation area, if the following standards 1. through 4. are met: <br />2. All of the stormwater runoff from the development site that will result from <br />the water quality design storm will be treated by a privately constructed and <br />maintained stormwater management facility prior to discharge. For purposes of <br />this subsection, the term “water quality design storm” means a theoretical storm <br />Page 61 of 87