20210804-00a: SER 5067 staff memo — original pdf

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ITEM FOR ENVIRONMENTAL COMMISSION AGENDA COMMISSION MEETING DATE: August 4, 2021 NAME & NUMBER OF PROJECT: Karanam Subdivision Wastewater Service Extension Request #5067 NAME OF APPLICANT OR ORGANIZATION: I.T. Gonzalez, I.T. Gonzalez Engineering LOCATION: 10802 D K Ranch Rd, Austin, TX 78759 COUNCIL DISTRICT: Limited Purpose Jurisdiction (Council District 10) PROJECT FILING DATE: June 17, 2021 WPD/ENVIRONMENTAL STAFF: Kaela Champlin, Environmental Program Coordinator (512) 974-3443, kaela.champlin@austintexas.gov WATERSHED: REQUEST: STAFF DETERMINATION: Bull Creek, Water Supply Suburban, Northern Edwards Aquifer Recharge Zone, Drinking Water Protection Zone Wastewater Service Extension Staff recommend approval of this service extension request.  MEMORANDUM July 28, 2021 Linda Guerrero, Chair, and Members of the Environmental Commission Kaela Champlin, Environmental Program Coordinator Watershed Protection Department TO: FROM: DATE: SUBJECT: Karanam Subdivision Wastewater Service Extension Request #5067 Service Extension Requests (SER) located in the Drinking Water Protection Zone and outside of the City of Austin’s full purpose jurisdiction require Council approval and review by the Environmental Commission. Watershed Protection Department staff have completed the review for Karanam Subdivision Wastewater Service Extension Request (SER) #5067 and recommend approval of the request. Site Overview The site consists of a tract of approximately 0.62 acres, located at 10802 D-K Ranch Road. The property is located in the City of Austin Limited Purpose Jurisdiction and Council District 10. The site is in the Bull Creek Watershed, Water Supply Suburban, the Drinking Water Protection Zone, and the Northern Edwards Aquifer Recharge Zone. The applicant is proposing to redevelop a single-family home into two single family homes on two separate lots. A site plan has not yet been submitted to the City of Austin at the time that staff reviewed this SER. The site is currently utilizing an On-Site Sewage Facility (OSSF) and is proposing a wastewater SER with two Living Unit Equivalents (LUEs). Development Impacts Water: The site is located in the Austin Water Service Area. Wastewater: The SER proposes that the applicant construct approximately 400 feet of appropriately sized low pressure force main from the existing 8-inch gravity wastewater main located in Nashfara Cove, and extend west along Nashfara Cove, and then south along D K Ranch Road to the subject tract, as approximately shown on the attached map. 1  Alternative Wastewater Service: Under Travis County Chapter 448.032(c)(1), each residential unit served by an OSSF is considered a separate structure. Multiple residential units may be on a single lot or site only if the lot or site contains at least one acre of land for each residential unit. A property owner cannot subdivide a single-family lot under one acre unless they have service extended to the site. If service is not extended to the site, the applicant will not be able to subdivide the property and the applicant would not be able to develop with a similar density with decentralized service. Environmental Impacts The property is in the Bull Creek Watershed and is classified as Water Supply Suburban. The site is in the Drinking Water Protection Zone and the Northern Edwards Aquifer Recharge Zone and drains to known Jollyville Plateau salamander (Eurycea sosorum) habitat. The site does not contain critical water quality zone, water quality transition zone, and there are no known critical environmental features on this site. An Environmental Resource Inventory (ERI) was not conducted for this SER. Recommendation Staff review determined that there are no significant environmental risks to extend service to the site. Therefore, the Watershed Protection Department staff recommend support for Wastewater SER #5067. The attached information provides further detail on the applicant’s request. Please feel free to contact Kaela Champlin at (512) 974-3443 or kaela.champlin@austintexas.gov if you have any questions or comments about the proposed SER. cc: Colleen Kirk, P.E., Austin Water Brett Ueno, P.E., Austin Water Liz Johnston, Watershed Protection Department 2 WATER AND WASTEWATER SERVICE EXTENSION REQUEST FOR CONSIDERATION Name: Karanam Subdivision Service Requested: Wastewater SER-5067 Hansen Service Request Number 914497 Date Received: 02/26/2021 Location: 10802 D K RANCH RD AUSTIN TX 78759 Karanam Subdivision Acres: 0.62 Land Use: SINGLE FAMILY LUE: 2 Alt. Utility Service or S.E.R. Number: City of Austin water service available Quad(s): G35 Reclaimed Pressure Zone: N/A DDZ: NO Drainage Basin: BULL Pressure Zone: NORTHWEST B DWPZ: YES Flow (Estimated Peak Wet Weather): 2 GPM Cost Participation: $0.00 % Within City Limits: 0 % Within Limited Purpose: 100 Description of Improvements: Applicant shall construct approximately 400 feet of appropriately sized low pressure force main from the existing 8-inch gravity wastewater main (Project No. 2015-0656; MH #268776) located in Nashfara Cv, and extend west along Nashfara Cv, and then south along DK Ranch Rd. to the subject tract, as approximately shown on the attached map. NOTES: 1) Wastewater flow based on engineering calculations received from I.T. Gonzalez, P.E. of I.T. Gonzalez Engineers on 2/26/2021. 2) Private pumping systems will be required for each proposed lot within the subject tract connecting to the proposed low pressure force main. Private pumping systems within the subject tract shall be owned, operated, and maintained by the property owner. Approval of this Service Extension Request is subject to completion and acceptance of the improvements described above and the conditions set forth below: 1) Construction of all Service Extensions is subject to all environmental and planning ordinances. 2) Service Extensions are subject to the guidelines established in the Land Development Code, Chapter 25-9, Water and Wastewater Utility Service. 3) An approved Service Extension is not a reservation of capacity in the system, but is an acknowledgment of the intent to serve. Available capacity shall be confirmed at the time a development application is submitted. 4) The level of service approved by this document does not imply commitment for land use. 5) Public utility mains must meet City of Austin Design and Construction Criteria and must be approved by Austin Water Engineering Review. 6) All onsite wastewater collection system components will be owned, operated, and maintained by the property owner. 7) An engineering report detailing the proposed low-pressure wastewater improvements shall be submitted to Austin Water Facility Engineering. 8) Applicant must adhere to City of Austin/Texas Commission on Environmental Quality design guidelines for any alternative wastewater collection system used. 9) Proposed public wastewater improvements will be dedicated to the City of Austin for ownership, operation, and maintenance. 10) Proposed public wastewater improvements must be placed in the public right-of-way or approved utility easements. Utility easements must be approved by Austin Water Engineering Review and must be in place prior to construction plan approval. 11) The approved Service Extension will automatically expire 180 days after date of approval unless a development application has been accepted by the Development Services Department. The Service Extension expires on the date the development expires, or if approved, on the date the development application approval expires. 12) Approval by the City Council will be required per Chapter § 25-9-35 of the Land Development Code. ?OSSF ?OSSF 9 4 6 ?OSSF ?OSSF 6 4 9 ?OSSF 944 9 4 2 ?OSSF ?OSSF 9 5 8 9 5 4 ?OSSF ?OSSF !P % \ % \ \ \ \ \ % TE \ X A \ % \ S P LU % C 8" PV \ 18" DI \ \ \ M \ E R 0 7 9 \ \ % D % \ \ 9 6 8 \ \ % \ % \ \ 18" DI \ \ \ \ % \ \ % !P \ \ \ \ \ % % STAFF PROPOSED APPROXIMATELY 400 FEET OF APPROPRIATELY SIZED LOW PRESSURE FORCE MAIN 6 6 9 ?OSSF 9 5 6 9 6 4 D H R C N A D K R 9 6 0 % !P268776 NASHFARA CV % 9 6 2 % 8" PVC ?OSSF ?OSSF G35 8 3 9 9 3 6 8 4 9 ?OSSF 9 2 8 9 3 2 0 4 9 6 2 9 9 2 4 9 3 4 ?OSSF?OSSF 9 4 2 9 5 8 2 5 9 0 5 9 0 5 9 SIM O N PL % !P % % 8 " P V % C % !P % C V P " %% !P 8 " P 8 !P % C V 0 3 9 . 0 50 100 200 300 Feet W.W. S.E.R. Name: Karanam Subdivision W.W. S.E.R. Number: 5067 Utility Development Services Plotted 6/8/2021 Subject Tract Full-Purpose City Limit 2-Mile ETJ Limited-Purpose City Limit This product is for informational purposes and may not have been prepared for or be suitable for legal, engineering, or surveying purposes. It does not represent an on-the-ground survey and represents only the approximate relative location of the property boundaries. This product has been produced by the City of Austin for the sole purpose of geographic reference. No warranty is made by the City of Austin regarding specific accuracy or completeness. DRAFT