Revised Final Order of Planning Commission on Remand from LUBA

Attachment B In regards to EC 9.6792 Stormwater Pollution Reduction, runoff from the proposed impervious surface areas will primarily be treated in planters (about 15 scattered throughout the development site). To ensure that the treated runoff will be discharged at pre-development levels, the rain gardens (planters) were sized using the City's Stormwater Surface Filtration/Infiltration Facility Sizing Spreadsheet. Runoff from the garage, driveway, and common house will be treated in a vegetated swale (approximately 10 feet wide and 58 feet long) located east of the common house. A proposed berm at the end of the swale will act as a weir to reduce flows to pre-development levels. As noted in the applicant's written statement, the swale was sized using the City's presumptive method. Public Works staff confirms that the proposed facilities are adequately sized to provide both pollution reduction and destination from the development site. The actual facility sizes and design will be more precisely determined during the building permit process and may be smaller or larger, based on actual impervious surface area and any impervious surface reduction techniques or in-kind facilities that may be provided at the time of development, provided they are consistent with the City's 2008 Stormwater Management Manual, and are not materially inconsistent with the approved final site plan. EC 9.6793 Stormwater Flow Control is not applicable because the subject property is below 500 feet in elevation and does not discharge to a headwaters stream. However, as discussed above, post-development flows will be limited to pre-development levels, in order to mimic existing drainage conditions. EC 9.6794 Stormwater Oil Control is not applicable because the proposed development will not generate high concentrations of oil and grease. EC 9.6796 Dedication of Stormwater Easements does not apply because the proposed stormwater facilities are to be privately operated and maintained. EC 9.6797 Stormwater Operation and Maintenance applies to all facilities designed and constructed in accordance with the stormwater development standards. This section also specifies when, and under what conditions, the public will accept function maintenance. Consistent with these standards, the applicant proposes private operation and maintenance of the on-site stormwater management facilities. To ensure compliance with EC 9.6797(3)(c), as proposed, the following condition of approval is necessary: • The final site plan shall note: "On-site stormwater management facilities will be privately owned and operated. An operation and maintenance plan will be developed consistent with the City's Stormwater Management Manual, and notice of this plan will be recorded, during the building permit process." With the findings, conditions, and future permit requirements noted above, staff finds that this criterion will be met. Based on these findings, the development will comply with this criterion. Hearings Official Decision (PDT 13-1, WG 13-1) 42