DEPARTMENT: Development Services
SUBJECT: TPV 21-082 Tree Preservation Variance for Crescent Hills Subdivision Units 2 & 3
SUMMARY:
Request by Mr. Richard Mott, P.E., 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 Southwest of Old Pearsall Rd and Loop 410 intersection. Staff recommends approval. (Herminio Griego, (210) 207-6042, herminio.griego@sanantonio.gov, Development Services Department)
BACKGROUND INFORMATION:
Project TRE-APP-APP21-38800378/Plat 21-18800142
Council District: 4
Consultant: Travis Elseth, P.E., with KFW Engineer
Staff Coordinator: Herminio Griego, Assistant City Arborist, (210) 207-6042
ANALYSIS:
The Development Services Department (DSD) has reviewed the information presented in Mr. Richard Mott’s letter dated May 26, 2021.
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 both the 100-year floodplain 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 significant trees more than the 80% preservation requirements within the 30’ floodplain buffer (environmentally sensitive area) in place under the 2010 Tree Preservation Ordinance for construction of the Crescent Hills Subdivision Units 2 & 3. DSD staff does agree with the applicant’s request to mitigate for the removal of significant trees below 80% for the following reasons:
Applicant Hardship:
Due to Atlas 14 floodplain delineation, the proposed site must be embanked to properly detain runoff and meet UDC regulations. Excess excavation and embankment are necessary to mitigate runoff by using the two proposed detention ponds on the property. Similarly, lots bordering the 100-year floodplain need to be embanked above the Atlas 14 inundation boundary to follow City of San Antonio design criteria. The mass grading of the proposed site result in the inability to preserve the few trees that are located within the 30’ Riparian Buffer.
1. Existing site conditions - The project site is moderately wooded with a canopy cover greater than or equal to 50%. The topography ranges from 0% - 10% and is located adjacent to the FEMA floodplain. No reclamation of the FEMA floodplain will occur for this project; therefore, no trees within the 100-year floodplain will be removed. However, 80% preservation could not be attained with the Riparian Buffer. There have been many attempts to revise the proposed site configuration and grading plan to preserve additional trees, but none were effective in meeting the buffer preservation requirements.
2. Tree mitigation- There are 4 protected trees, or 52”, located within floodplain buffer. A total of 32” (2 trees) will be preserved resulting in 62% preservation. The total mitigation required for falling below 80% preservation of significant trees within the floodplain buffer is 9.6 caliper inches. The owner proposes to mitigate by upsizing the required 2 trees per lot from 1.5” to 2” across 162 lots. The total mitigation provided is 162 inches which is152.4 inches above the required minimum mitigation of 9.6 inches. The 324 trees to be planted provides added species diversity to include native medium and large species trees per San Antonio Recommended Plant List.
DSD staff supports the applicant’s request to fall below 80% preservation of significant trees within the 30’ Floodplain Buffer based on the conditions of the site, design constraints, and exceeding mitigation requirements. The proposed Variance Request meets the intent and spirit of the Tree Ordinance therefore, staff recommends approval.