DEPARTMENT: Development Services
SUBJECT: TPV 19-021 Tree Preservation Variance for Union Pacific Railroad Bridge 8.82 Replacement
SUMMARY:
Request by Ms. Jean Devlin for approval of a tree preservation variance request from Unified Development Code 35-523 (h), “significant trees shall be preserved at eighty (80) percent and heritage trees at one hundred (100) percent preservation within both the 100-year floodplains and environmentally sensitive areas”, general located at 12078 Southton Road. Staff recommends approval. (Herminio Griego, (210) 207-6042, herminio.griego@sanantonio.gov, Development Services Department)
BACKGROUND INFORMATION:
Project A/P# 2468597
Council District: 3
Consultant: Ms. Jean Devlin of HDR Engineering.
Staff Coordinator: Herminio Griego, Assistant City Arborist, (210) 207-6042
ANALYSIS:
The Development Services Department (DSD) reviewed the information presented in Ms. Jean Devlin’s letter dated March 12, 2019 (paid May 8, 2019).
The Unified Development Code (UDC) - Article V, Section 35-523 (h), 100-Year Floodplain(s) and Environmentally Sensitive Areas states that, “Significant trees shall be preserved at eighty (80) percent preservation within both the 100-year floodplains and environmentally sensitive areas. Mitigation shall be prohibited in floodplains and environmentally sensitive area except when a variance is granted by the Planning Commission.”
The applicant is requesting a Variance Request to mitigate for removal of surveyed trees within the Riparian Buffer in excess of the 80% minimum preservation of protected significant trees in place under the 2010 Tree Preservation Ordinance for the Union Pacific Railroad Bridge 8.82 replacement project. DSD staff does agree with the applicant’s request to mitigate via paying into the Tree Mitigation Fund and by reseeding for tree survey inches determined to be below 80% significant tree preservation for the following reasons:
1. Existing site conditions - This project includes the replacement of Union Pacific Railroad’s (UPRR) Bridge 8.82 wooden bridge with a pre-stressed concrete bridge. The purpose of the bridge replacement will ensure safe and reliable railroad transportation service. Project activities will result in the removal of significant trees in the Riparian Buffer below the 80% preservation requirements. The bridge replacement activities are limited to the 100-foot UPRR right-of-way and approximately 50 feet north and south of the bridge abutments. The bridge replacement activities require removing 33 of 61 significant tree inches in the Riparian Buffer resulting in 46% preservation within the buffer area and 21 inches of mitigation.
2. Tree mitigation and canopy diversity - The applicant opted to provide mitigation above and beyond the minimum required in the UDC as identified below: The project will meet the Riparian Buffer tree survey mitigation requirements as follows:
a. Re-seeding approximately 21,780 square feet of disturbed area within the flood plain and adjacent Riparian Buffer;
b. Reclaiming disturbed areas by drill seeding with a native seed mix and ensuring 85% establishment; and
c. Paying $4,200.00 into the Tree Mitigation Fund.
DSD staff supports the applicant’s request to fall below 80% Significant Tree requirements in the Riparian Buffer based on the conditions of the site and the need to ensure safe and reliable locomotive transportation, going above and beyond the UDC requirements with regard to reclamation activities and paying into the Tree Mitigation Fund. The proposed Variance Request meets the intent and spirit of the Tree Ordinance therefore, staff recommends approval.