20251203-002: Arbor View Variance Staff Findings of Fact — original pdf

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ITEM FOR ENVIRONMENTAL COMMISSION AGENDA COMMISSION MEETING DATE: 12/3/2025 NAME & NUMBER OF PROJECT: NAME OF APPLICANT OR ORGANIZATION: Arbor View Subdivision; C8-2025-0085.0A Mirza Baig, PE; Terrence Irion LOCATION: 4316 Far West Blvd, Austin, TX 78731 COUNCIL DISTRICT: District 10 ENVIRONMENTAL REVIEW STAFF: WATERSHED: REQUEST: Mike McDougal Environmental Policy Program Manager Austin Development Services 512-974-6380 mike.mcdougal@ausintexas.gov Bull Creek Watershed Water Supply Suburban Drinking Water Protection Zone Variance request is as follows: 1. Request to vary from LDC 25-8-301 to allow construction of a driveway on slopes over 15% 2. Request to vary from LDC 25-8-302 to allow construction of buildings on slopes over 15% 3. Request to vary from LDC 25-8-423 to exceed the 30% net site area watershed impervious cover limit and to allow 3900 square feet of impervious cover Page 2 of 2 STAFF RECOMMENDATION: Staff does not recommend this variance, having determined that the findings of fact have not been met. STAFF CONDITIONS: 1. Impervious cover shall be limited to 3,900 sq ft for “Lot 1” and 0 sq ft for “Lot 2”. 2. Prior to issuance of the COA building permit, the applicant must have an approved COA exemption for detention of 3,900 sq ft of impervious cover and an easement. 3. The detention will be maintained in accordance with COA requirements. 4. Slab-on-grade foundation construction is not allowed. The foundation and driveway must be constructed using piers. Any grading exceeding four feet of depth or construction on slopes exceeding 15% will require Land Use Commission variances in accordance with applicable Land Development Code regulations. 5. The design and construction of structures on the lot must be based on the recommendations from a slope stability analysis performed by a licensed geotechnical engineer, as verified by the City. Development Services Department Staff Recommendations Concerning Required Findings Project Name: Arbor View Subdivision Ordinance Standard: Watershed Protection Ordinance (current Code) Variance Request: Request to vary from LDC 25-8-301 to allow construction of a driveway on slopes over 15%; and Request to vary from LDC 25-8-302 to allow construction of buildings on slopes over 15% A. Land Use Commission variance determinations from Chapter 25-8-41 of the City Code: 1. The requirement will deprive the applicant of a privilege available to owners of other similarly situated property with approximately contemporaneous development subject to similar code requirements; Yes - current Code generally restricts development to slopes of 15% or less. All applicants are required to comply with construction on slopes limits either by reducing the scope of the project, by redesigning the project, or by creating lots in a configuration that will facilitate Code compliant development. The lots to the immediate west, north, and east were platted as single family subdivision lots in 1981, 1993, and 1965, respectively. Consequently, it is not feasible to adjust the configuration of the proposed single family lot to create a reasonably buildable lot. Additionally, nearly the entire property consists of slopes over 15%; it is not possible to adjust the scope or layout of the project to comply with construction on slopes limits. Current review practice discourages leaving unbuildable lots located adjacent to and outside of proposed subdivisions to avoid the creation of future unbuildable lots that will require variances. 2. The variance: a. is not necessitated by the scale, layout, construction method, or other design decision made by the applicant, unless the design decision provides greater overall environmental protection than is achievable without the variance; Yes - the variances are not necessitated by the scale, layout, construction method, or other design decision made by the applicant. The lot is surrounded by property zoned single family. The property is also zoned single family. However, if the zoning were commercial or multi-family, the property would require the same variances to allow construction on slopes for any proposed construction of driveways / drive aisles, parking, and building(s). The property is unbuildable without the requested variances. b. is the minimum deviation from the code requirement necessary to allow a reasonable use of the property; and Yes – at the time of single family subdivision platting, the exact size of future single family homes is often unknown. Consequently, the Land Development Code directs Environmental Review Staff to assume 5000 square feet of impervious cover for proposed single family lots of this size when reviewing proposed single family subdivision plats. The applicant proposes to build 3900 square feet of impervious cover; the applicant proposes to build the entire project on piers to minimize ground disturbance during construction and to avoid requesting two more variances to exceed grading limits. c. Does not create a significant probability of harmful environmental consequences; and No – the City of Austin Environmental Criteria Manual states: The conversion of land from its natural state to urban use accelerates the processes of erosion and sedimentation. These negatively impact the city's drinking water supply, aquatic life and the recreational resource provided by them. Construction related sediment can be a significant pollutant of streams, lakes, ponds and reservoirs. Not only does sediment reduce the quality of water for boating, fishing, swimming and other water-oriented recreation, it also creates maintenance problems due to excessive wear on pumps and due to the reduced capacity of streams, lakes and other waterways. The Land Development Code generally limits construction to slopes of 15% or less to limit erosion / sedimentation damage to water quality and adjacent vegetation. Steeper slopes generate and transport greater amounts of sediment during construction than shallower slopes; sediment containment (i.e., erosion / sedimentation control methods) during construction is much less feasible on steeper slopes; and replacing soil after construction, site stabilization, and site revegetation are substantially more difficult and less likely to succeed on steeper slopes. Slopes on the site generally exceed 70%. To reduce the environmental impact of construction on steep slopes, the applicant proposes to build the single family development on piers. However, establishing vegetation to stabilize soil beneath the development is impossible due to an absence of light. Consequently, soil beneath the development will remain unstabilized. 3. Development with the variance will result in water quality that is at least equal to the water quality achievable without the variance. Yes – based on the Land Development Code, water quality treatment is not required for this proposed subdivision. As a Staff condition of variance approval, the applicant will limit the total impervious cover to 3900 square feet (rather than the 5000 square feet assumed by LDC 25-8-64 for the proposed lot) and, rather than using the more conventional slab-on-grade construction, the foundation as well as driveway will be built on piers to minimize ground disturbance The Land Use Commission may grant a variance from a requirement of Article 7, Division 1 ( Critical Water Quality Zone Restrictions ), after determining that: B. Additional Land Use Commission variance determinations for a requirement of Section 25- 8-422 (Water Quality Transition Zone), Section 25-8-452 (Water Quality Transition Zone), Section 25-8-482 (Water Quality Transition Zone), Section 25-8-652 (Restrictions on Development Impacting Lake Austin, Lady Bird Lake, and Lake Walter E. Long), or Article 7, Division 1 (Critical Water Quality Zone Restrictions): 1. The criteria for granting a variance in Subsection (A) are met; N/A 2. 3. The requirement for which a variance is requested prevents a reasonable, economic use of the entire property; N/A The variance is the minimum deviation from the code requirement necessary to allow a reasonable, economic use of the entire property. N/A Staff Determination: Staff determines that the findings of fact have not been met. In the event that the requested variances are recommended for approval by the Environmental Commission, Staff offers the following conditions: 1. Impervious cover shall be limited to 3,900 sq ft for “Lot 1” and 0 sq ft for “Lot 2”. 2. Prior to issuance of the COA building permit, the applicant must have an approved COA exemption for detention of 3,900 sq ft of impervious cover and an easement. 3. The detention will be maintained in accordance with COA requirements. 4. Slab-on-grade foundation construction is not allowed. The foundation and driveway must be constructed using piers. Any grading exceeding four feet of depth or construction on slopes exceeding 15% will require Land Use Commission variances in accordance with applicable Land Development Code regulations. 5. The design and construction of structures on the lot must be based on the recommendations from a slope stability analysis performed by a licensed geotechnical engineer, as verified by the City. Environmental Review (ADS) _____________________________ Date: 11/13/2025 Mike McDougal Environmental Policy Program Manager (ADS) _____________________________ Mike McDougal Date: 11/13/2025 Environmental Officer (AWP) _____________________________ Liz Johnston Date:________________ Development Services Department Staff Recommendations Concerning Required Findings Project Name: Arbor View Subdivision Ordinance Standard: Watershed Protection Ordinance (current Code) Variance Request: Request to vary from LDC 25-8-423 to exceed the 30% net site area watershed impervious cover limit and to allow 3900 square feet of impervious cover A. Land Use Commission variance determinations from Chapter 25-8-41 of the City Code: 1. The requirement will deprive the applicant of a privilege available to owners of other similarly situated property with approximately contemporaneous development subject to similar code requirements; Yes - due to the steep slopes on this property and the net site area calculation required by Code and Criteria, the 30% allowable watershed impervious cover limit equals approximately 232 square feet. The applicant cannot build a single family development in compliance with the watershed impervious cover limit. All applicants are required to comply with the watershed impervious cover limit either by reducing the scope of the project, by redesigning the project, or by creating lots in a configuration that will facilitate Code compliant development. The lots to the immediate west, north, and east were platted as single family subdivision lots in 1981, 1993, and 1965, respectively. Consequently, it is not feasible to adjust the configuration of the proposed single family lot to create a reasonably buildable lot. Additionally, it is not feasible to build a single family project and a driveway in compliance with the approximately 232 square foot watershed impervious cover limit. Current review practice discourages leaving unbuildable lots located adjacent to and outside of proposed subdivisions to avoid the creation of future unbuildable lots that will require variances. 2. The variance: a. is not necessitated by the scale, layout, construction method, or other design decision made by the applicant, unless the design decision provides greater overall environmental protection than is achievable without the variance; Yes - the variance is not necessitated by the scale, layout, construction method, or other design decision made by the applicant. The lot is surrounded by property zoned single family. The property is also zoned single family. However, if the zoning were commercial or multi-family, the property would require the same variance to exceed the watershed impervious cover limit. The property is unbuildable without the requested variance. b. is the minimum deviation from the code requirement necessary to allow a reasonable use of the property; and Yes – at the time of single family subdivision platting, the exact size of future single family homes is unknown. Consequently, the Land Development Code directs Environmental Review Staff to assume 5000 square feet of impervious cover for proposed single family lots of this size when reviewing proposed single family subdivision plats. The applicant proposes to build 3900 square feet of impervious cover; the applicant proposes to build the entire project on piers to minimize ground disturbance during construction and to avoid requesting two more variances to exceed grading limits. c. Does not create a significant probability of harmful environmental consequences; and No – impervious cover degrades water quality. When the ground is covered with impervious surfaces, water cannot infiltrate the soil. Instead, water runs across the impervious surfaces, picking up pollutants, and sediment. These pollutants drain to waterways. In contrast, in an undeveloped environment, soil and vegetated surfaces can absorb and infiltrate water; and this water moves through the soil slowly, taking a longer, indirect path to waterways that allows more time for sediment and pollutants to be removed from the water through natural physical, biological, and chemical processes. Impervious cover negatively impacts the city's drinking water supply and aquatic life. The Land Development Code establishes watershed impervious cover limits to reduce the pollutant load created by impervious surfaces. 3. Development with the variance will result in water quality that is at least equal to the water quality achievable without the variance. Yes – based on the Land Development Code, water quality treatment is not required for this proposed subdivision. As a Staff condition of variance approval, the applicant will limit the total impervious cover to 3900 square feet (rather than the 5000 square feet assumed by LDC 25-8-64 for the proposed lot) and, rather than using the more conventional slab-on-grade construction, the foundation as well as driveway will be built on piers to minimize ground disturbance The Land Use Commission may grant a variance from a requirement of Article 7, Division 1 ( Critical Water Quality Zone Restrictions ), after determining that: B. Additional Land Use Commission variance determinations for a requirement of Section 25- 8-422 (Water Quality Transition Zone), Section 25-8-452 (Water Quality Transition Zone), Section 25-8-482 (Water Quality Transition Zone), Section 25-8-652 (Restrictions on Development Impacting Lake Austin, Lady Bird Lake, and Lake Walter E. Long), or Article 7, Division 1 (Critical Water Quality Zone Restrictions): 1. The criteria for granting a variance in Subsection (A) are met; N/A 2. 3. The requirement for which a variance is requested prevents a reasonable, economic use of the entire property; N/A The variance is the minimum deviation from the code requirement necessary to allow a reasonable, economic use of the entire property. N/A Staff Determination: Staff determines that the findings of fact have not been met. In the event that the requested variances are recommended for approval by the Environmental Commission, Staff offers the following conditions: 1. Impervious cover shall be limited to 3,900 sq ft for “Lot 1” and 0 sq ft for “Lot 2”. 2. Prior to issuance of the COA building permit, the applicant must have an approved COA exemption for detention of 3,900 sq ft of impervious cover and an easement. 3. The detention will be maintained in accordance with COA requirements. 4. Slab-on-grade foundation construction is not allowed. The foundation and driveway must be constructed using piers. Any grading exceeding four feet of depth or construction on slopes exceeding 15% will require Land Use Commission variances in accordance with applicable Land Development Code regulations. 5. The design and construction of structures on the lot must be based on the recommendations from a slope stability analysis performed by a licensed geotechnical engineer, as verified by the City. Environmental Review (ADS) _____________________________ Date: 11/13/2025 Mike McDougal Environmental Policy Program Manager (ADS) _____________________________ Mike McDougal Date: 11/13/2025 Environmental Officer (AWP) _____________________________ Liz Johnston Date:________________