DEPARTMENT: Development Services
SUBJECT: TPV 19-010 Tree Preservation Variance for Davis Ranch Units 3A, 3B, 4A and 4B
SUMMARY:
Request by Mr. Jon Robinson, RLA, 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 on Galm Road and Swayback Ranch. Staff recommends approval. (Herminio Griego, (210) 207-6042, Herminio.griego@sanantonio.gov, Development Services Department)
BACKGROUND INFORMATION:
Project A/P# 2422847
Council District: 6
Consultant: Jon Robinson, RLA with Horizon Design Landscape Architecture
Staff Coordinator: Herminio Griego, Assistant City Arborist, (210) 207-6042
ANALYSIS:
The Development Services Department (DSD) has reviewed the information presented in Mr. Jon Robinson’s letter dated January 11, 2019 letter received on January 16, 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 significant tree and one hundred (100%) percent heritage tree 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 30’ Riparian Buffer in excess of the 80% and 100% minimum preservation of protected significant and heritage trees respectively in place under the 2015 Tree Preservation Ordinance for development of the Davis Ranch Units 3A, 3B, 4A, and 4B project. DSD staff does agree with the applicant’s request to mitigate via planting for tree survey inches determined to be below 80% significant and 100% heritage tree preservation for the following reasons:
1. Existing site conditions - The project includes approximately 68.85 acres with the the construction of 1,070 linear feet of the Davis Ranch Parkway, 231 new single family residential lots, and overhead electrical service located on the western property boundary. The western property boundary includes a 30’ Riparian Buffer adjacent to a regulatory floodplain. The Riparian Buffer includes 1,833 inches of Significant Trees and 127 inches of Heritage Trees. The electrical service provider requires overhead electrical service from the public connection to the individual residential lots, and 28’ electrical easements on the western property boundary and removal of all trees within the easement. The electrical easement overlaps the Riparian Buffer for 90% of its length. Therefore the electrical service provider requirements will result in tree removal in Riparian Buffer below the UDC requirements.
2. Due to existing site conditions, electrical service provider requirements, and the location of the electrical easement mostly within the Riparian Buffer the project is unable to preserve the minimum 80% of Significant and 100% of heritage trees surveyed along the project’s western boundary. The project and preservation data are presented in the table below:
|
|
Riparian Buffer |
Units |
|
Significant Tree Survey Data |
|
|
|
Total Inches |
1,833 |
Inches |
|
Preserved & Credit Inches |
1,404.3 |
Inches |
|
Removed Inches |
456 |
Inches |
|
Preserved % |
76.61 |
% |
|
Required % |
80 |
% |
|
|
|
|
|
Heritage Tree Survey Data |
|
|
|
Total Inches |
127 |
Inches |
|
Preserved Inches |
74 |
Inches |
|
Removed Inches |
53 |
Inches |
|
Preserved % |
58.3 |
% |
|
Required % |
100 |
% |
|
|
|
|
|
Mitigation |
|
|
|
Significant |
62.1 |
Inches |
|
Heritage |
159 |
Inches |
|
Total |
221.1 |
Inches |
Note: Credits from cluster preservation (Section 35.523(i)(3)
3. Required mitigation for the tree survey is 221.1 inches as depicted in the table above:
4. 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:
|
MITIGATION MECHANISM |
MITIGATION |
APPLIED TOWARD |
|
A. Re-seeding disturbed area in Riparian Buffer NOTE: Re-seeding will consist of an approved native seed mix applied by drill seeding and established to 85%. |
124 Cal. Inches |
Riparian Buffer Mitigation |
|
B. Upsizing (1) Required tree per lot to 3” |
346.5 Cal Inches |
Riparian buffer Mitigation |
|
Total Riparian Buffer Mitigation Provided: |
470.5 Cal. Inches |
|
|
Total Riparian Buffer Mitigation Required: |
221.1 Cal. Inches |
|
|
|
|
|
|
Excess Riparian Buffer Mitigation Provided: |
249.4 Cal. Inches |
|
5. The Davis Ranch Units 3A, 3B, 4A and 4B Final tree Canopy required at 38% is 1,026,193 square feet. The total Final Tree Canopy provide is 1,882,015 square feet; resulting in 855,822 square feet of excess tree canopy for a total of 183% area of tree canopy.
DSD staff supports the applicant’s request to fall below 80% Significant Tree an 100% Heritage Tree preservation requirements in 30’ Riparian Buffer based on the conditions of the site, electrical service provider requirements, and exceeding mitigation and tree survey and final canopy cover requirements. The proposed Variance Request meets the intent and spirit of the Tree Ordinance therefore, staff recommends approval.