DEPARTMENT: Development Services
SUBJECT: TPV 19-036 Tree Preservation Variance for SAWS Silverhorn Golf Course 24-Inch Rehab
SUMMARY:
TPV 19-036 Tree Preservation Variance for SAWS Silverhorn Golf Course 24-Inch Rehab: Request by Mr. Michael Persyn 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”, located along the Silverhorn Golf Course. Staff recommends approval. (Herminio Griego, (210) 207-6042, herminio.griego@sanantonio.gov, Development Services Department)
BACKGROUND INFORMATION:
Project A/P# 2487238
Council District: 9
Consultant: Mr. Michael Persyn
Staff Coordinator: Herminio Griego, Assistant City Arborist, (210) 207-6042
ANALYSIS:
The Development Services Department (DSD) reviewed the information presented in Mr. Michael Persyn letter dated July 15, 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. Heritage trees shall be preserved at one-hundred (100) percent preservation within 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 an Environmental Variance to mitigate for removal of tree stand delineated trees within the Floodplain and Environmentally Sensitive Areas in excess of the 80% minimum preservation of protected significant trees in place under the 2010 Tree Preservation Ordinance for development of San Antonio Water System (SAWS) Silverhorn Golf Course 24-Inch Rehab project (the Project). DSD staff does agree with the applicant’s request to mitigate via enhanced revegetation and payment into the Tree Mitigation Fund for tree stand determined to be below 80% significant tree preservation in the floodplain and environmentally sensitive areas for the following reasons:
1. Existing site conditions - The Silverhorn Golf Course 24-Inch Rehab project is required pursuant to the agreement between the City of San Antonio and the United States Environment Protection Agency to address deteriorated sanitary sewer infrastructure within the Silverhorn Golf Course in City of San Antonio. The Project is essential for the health and welfare of San Antonio’s citizenry. The Project consists of replacing 3,470 linear feet of deteriorated thirty-five (35) year old twenty-four (24) inch diameter sanitary sewer pipe using trenchless techniques.
The majority of the project is located within the 100-year floodplain. SAWS decided to use the Cure In Place Pipe (CIPP - trenchless technique) methodology to minimize the impact on stands of trees within the Project limits. Even though replacement will be with trenchless techniques, the Project requires the removal of tree stand for access to the sanitary sewer.
The Tree Stand Delineation Plan indicates that seventy two (72) percent of the total canopy in the floodplain will be preserved; fifty (50) percent of the canopy will be preserved in the environmentally sensitive areas (ESA); and approximately forty-five (45) percent of the canopy will be preserved in the non-floodplain/non-ESA. The Project includes one-hundred (100) percent preservation of the 109 inches of heritage trees within the operating limits.
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 Floodplain Tree Stand Delineation mitigation requirements as follows:
a. Re-seeding six (6) acres of disturbed area, both inside and outside of the floodplain;
b. Reclaiming disturbed areas by drill seeding with a native seed mix and ensuring 85% establishment; and
c. Payment into the Tree Mitigation fund of $16,700.00:
SAWS is requesting consideration of a fifty percent (50%) reduction in the mitigation fee for going above and beyond with regards to reseeding techniques inside and outside of the floodplain and environmentally sensitive areas. If approved, the reduced mitigation payment would be $ 8,350.00.
DSD staff supports the applicant’s request to fall below 80% tree stand in the floodplain and ESA based on the conditions of the site, need to replace existing deteriorated sanitary sewer lines with new sanitary sewer lines, and exceeding mitigation and tree stand delineation requirements. The proposed Variance Request meets the intent and spirit of the Tree Ordinance therefore, staff recommends approval.