20200115-008b: Austin Green PUD C814-2018-0154 Recommendation — original pdf

Recommendation

ENVIRONMENTAL COMMISSION MOTION 20200115 008b Date: January 15, 2020 Subject: Austin Green Planned Unit Development, C814-2018-0154 Motion by: Katie Coyne Seconded by: Mary Ann Neely RATIONALE: WHEREAS, increased development pressure to the City’s east will make it even more vital to develop in environmentally sensitive ways; WHEREAS, the site is identified in Imagine Austin as a Town Center; WHEREAS, the applicant is committed to dedicating over 858.22 acres, approximately 40% of the site, as parkland or open space; WHEREAS, the applicant is committed to meeting existing code or in most cases, exceeding Planned Unit Development (PUD) superiority requirements; WHEREAS, the applicant is requesting approval to create a new PUD with superior environmental design; WHEREAS, the applicant is committed to restoring previously industrial land to functioning riparian and open space assets; and WHEREAS, City of Austin Staff recommends the approval with conditions outlined below. THEREFORE, approval of the requested PUD creation with the ongoing commitment of the applicant to meet superiority elements outlined in the meeting backup, and with the following conditions: Environmental Commission Conditions: 1. That the applicant continue to work with and get approval from the Watershed Protection department for a land management and maintenance plan for parkland, open space, riparian zones, green infrastructure features, and other environmentally sensitive areas on site to ensure the long-term environmental function of the landscapes; and, that the applicant commit to this plan in the long-term. 2. Explore carbon capture credits and other mitigation banking that may encourage climate action / carbon 3. 858.22 (40%) acres of public open space and parkland, which includes approximately three miles of Colorado sequestration efforts regionally. River frontage shall be provided. 1 4. Open space areas shall be restored with appropriate native vegetation outlined in the PUD. 5. Parks and open space areas shall utilize reclaimed water for irrigation. 6. 65% of stormwater shall be treated by dispersed green stormwater infrastructure which includes bio- filtration, rain gardens, and vegetated filter strips. 7. 77 acres of off-site drainage area shall be treated. 8. The project shall provide approximately 50 million cubic feet of additional storage volume for the watershed through a series of on-site retention ponds. Approximately 100 million cubic feet of additional storage volume shall be provided beyond the minimum required for on and off-site flows through three (3) on-site regional retention ponds for the Elm Creek watershed. The proposed 450-acre retention ponds will remove approximately 238 acres of neighboring property and 43 acres of Harold Green Road Right Of Way from the floodplain. These calculations are based on the Atlas 14 flood model for the adjusted 100-year floodplain. 9. Shall provide 29 acres of additional critical water quality zone. 10. Shall preserve 12.91 acres of wetland Critical Environmental Features (CEFs), 12.74 acres of wetland CEFs shall be enhanced and 9.97 acres of wetland CEFs shall be mitigated at 150% acre-for-acre and given the 150-foot buffer required by code. 11. Impervious cover shall be capped at 65% gross site area. 12. Shall preserve a significant stand of trees that have been identified on-site and shall meet current code for tree removal and mitigation. 13. Shall provide 6 miles of public trails throughout the development. 14. Shall meet a Carbon Impact score of 8. VOTE 8-0 For: Bedford, Smith, Creel, Thompson, Guerrero, Coyne, Neely, and Maceo Against: None Abstain: None Recuse: Ramberg Absent: Nill and Gordon Approved By: Linda Guerrero, Environmental Commission Chair 2