20200916-004b: 8921 US Hwy 290 West wastewater SER #4796 Memo — original pdf

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ITEM FOR ENVIRONMENTAL COMMISSION AGENDA COMMISSION MEETING DATE: September 16, 2020 NAME & NUMBER OF PROJECT: 8921 US Hwy 290 West Wastewater Service Extension Request #4796 NAME OF APPLICANT OR ORGANIZATION: Joe Longaro, P.E. LJA Engineering, Inc. LOCATION: 8921 US 290 Hwy West, Austin, TX 78737 COUNCIL DISTRICT: Austin 2-Mile Extraterritorial Jurisdiction PROJECT FILING DATE: May 18, 2020 WPD/ENVIRONMENTAL STAFF: Kaela Champlin, Environmental Program Coordinator, Watershed Protection Department (512) 974-3443, kaela.champlin@austintexas.gov Slaughter Creek Watershed, Barton Springs Zone, Edwards Aquifer Contributing Zone, Drinking Water Protection Zone WATERSHED: REQUEST: STAFF DETERMINATION: Wastewater Service Extension Staff recommends approval 1  TO: FROM: MEMORANDUM Linda Guerrero, Chair, and Members of the Environmental Commission Kaela Champlin, Environmental Program Coordinator, Watershed Protection Department September 9, 2020 DATE: SUBJECT: 8921 US Hwy 290 West Wastewater SER #4976 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 8921 US Hwy 290 West wastewater SER #4976 and recommend approval of the request. Site Overview The site consists of one tract of approximately 69.12 acres, located at 8921 W US 290 Hwy. The site is in the City of Austin’s Limited Purpose Jurisdiction, the Slaughter Creek Watershed, the Barton Springs Zone, and the Drinking Water Protection Zone. The site is also within the Edwards Aquifer Contributing Zone and is subject to the Composite Ordinance due to 245 determination. This property has an approved site plan for the Junction Athletic Complex, SP-2016-0607D, a proposed sports complex that has not been constructed. The applicant is now proposing to develop a 280-unit multi-family project in the same development footprint with 140 Land Use Equivalents (LUEs). A revised site plan has not yet been submitted; however, the applicant will comply with the development requirements of the approved site plan. This site is also adjacent to the Ledgestone Multifamily wastewater SER #4622, located at 9021 W US 290 Hwy, approved by Council on June 11, 2020. Environmental Impacts The eastern portion of the site is within the Devils Pen Creek critical water quality zone and water quality transition zone. There are seven wetland critical environmental features (CEFs) and one seep CEF on the property. The site does not drain to occupied salamander habitat. 2  Development Impacts Water: The site is located in the water service area of the West Travis County Public Utility Agency (PUA). Wastewater: The applicant has proposed to construct approximately 1,000 feet of 8-inch gravity wastewater main in Circle Dr and extend south along Circle Dr and then west along US 290 to the highest point that can be served by the proposed gravity wastewater main, as approximately shown on the attached map. The applicant has also proposed to construct an appropriately sized public lift station at the approximate location shown on the attached map. The applicant proposes to construct approximately 6,000 feet of appropriately sized force main from the proposed lift station and extend north through the subject tract and northeast along US 290 Hwy to the proposed 8-inch gravity wastewater main in US 290 Hwy. Applicant shall dedicate the appropriately sized wastewater easements from the proposed lift station to the western property line and north to W US 290 Hwy. A conceptual drawing of the proposed wastewater main and lift station is provided in the attached SER application. Construction of the wastewater main and lift station are required by LDC Chapter 25-8 to be located outside of the water quality transition zone and critical water quality zone. The layout of the proposed lift station will be reviewed when the project is submitted for site plan review and must comply with City Code. Should the applicant choose to pursue a lift station on this property that is in the critical or water quality transition zone, a variance approved by the Land Use Commission would be required. Staff would not recommend the variance, as the findings of fact required by the City’s Land Development Code would not be met. The applicant also proposes to construct approximately 1,800 feet of 15-inch gravity wastewater main (minimum 0.5% slope) from the existing 15-inch gravity wastewater main along Williamson Creek, and extend west to the existing 12-inch gravity wastewater main located west of Covered Bridge Dr, as approximately shown on the attached map. The proposed 15-inch gravity wastewater main shall replace the existing 12-inch gravity wastewater main along its path. Applicant shall reconnect all existing wastewater services from the existing 12-inch gravity wastewater main to the proposed 15-inch gravity wastewater main. The applicant proposes to construct approximately 2,250 feet of 12-inch gravity wastewater main (minimum 1.0% slope) from the existing 8-inch gravity wastewater main located north of Towana Trl, and extend south towards Towana Trl, west along Towana Trl, and then south along Mowinkle Dr to the existing 8-inch gravity wastewater main in Mowinkle Dr, as approximately shown on the attached map. The proposed 12-inch gravity wastewater main shall replace the existing 8-inch gravity wastewater main along its path. Applicant shall reconnect all existing wastewater services from the existing 8-inch gravity wastewater main to the proposed 12-inch gravity wastewater main. 3  The appropriately sized lift station and force main shall be sized to provide service to the subject tract only. However, the adjacent tract (Ledgestone SER #4622) also requires a lift station and force main, and the applicant has indicated that it is preferable that only one lift station be constructed to serve both tracts. Approximately 1,600 feet of the 1,800 feet of 15-inch gravity wastewater main is also proposed to be constructed by Granada Ridge (SP-2018-0138, SER #3299). If the applicant’s project timeline needs these wastewater improvements prior to the completion of them by others, then the design and construction of these improvements are the responsibility of the applicant. The proposed 1,800 feet of 15-inch gravity wastewater main, 2,500 feet of 12-inch gravity wastewater main, 1,000 feet of 8-inch gravity wastewater main, and a portion of the 6,000 feet of appropriately sized force main is also proposed to be constructed by Ledgestone SER #4622. If the applicant’s project timeline needs these wastewater improvements prior to the completion of them by others, then the design and construction of these improvements are the responsibility of the applicant. Alternative Wastewater Service: The site is allowed 20% net site area impervious cover, and up to 25% net site area with transfers. If service is not extended to the site and wastewater disposal is required under a Texas Land Application Permit (TLAP) issued by the Texas Commission on Environmental Quality, wastewater irrigation fields would be required on the site. Due to the environmental sensitivity of this tract, staff recommends the SER extension as opposed to a TLAP. Recommendation Based on the approved site plan and vested rights on the property, and if service were not extended, alternative wastewater service could create negative environmental conditions on the site; WPD staff recommend approval of Service Extension Request #4796. 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: Brett Ueno, P.E., Austin Water Colleen Kirk, P.E., Austin Water Christopher Herrington, P.E., Watershed Protection Department 4 WATER AND WASTEWATER SERVICE EXTENSION REQUEST FOR CONSIDERATION Name: 8921 Hwy 290 West Service Requested: Wastewater SER-4796 Hansen Service Request Number 853239 Date Received: 05/18/2020 Location: 8921 W US 290 HWY AUSTIN TX 78737 8921 Hwy 290 West Acres: 69.12 Land Use: MULTI FAMILY LUE: 140 Alt. Utility Service or S.E.R. Number: Water service provided by others Quad(s): WZ18 WZ19 Reclaimed Pressure Zone: N/A DDZ: NO Drainage Basin: SLAUGHTER Pressure Zone: SOUTHWEST C DWPZ: YES Flow (Estimated Peak Wet Weather): 131 GPM Cost Participation: $0.00 % Within City Limits: 0 % Within Limited Purpose: 0 Description of Improvements: Applicant shall construct approximately 1,000 feet of 8-inch gravity wastewater main from the existing 8-inch gravity wastewater main (Project No. 2009-0588; MH #240187) in Circle Dr, and extend south along Circle Dr and then west along US 290 Hwy to the highest point that can be served by the proposed gravity wastewater main, as approximately shown on the attached map. Applicant shall also construct an appropriately sized public lift station at the approximate location shown on the attached map. Applicant shall construct approximately 6,000 feet of appropriately sized force main from the proposed lift station and extend north through the subject tract and then northeast along US 290 Hwy to the proposed 8-inch gravity wastewater main in US 290 Hwy. Applicant shall dedicate appropriately sized wastewater easements from the proposed lift station to the western property line and north to W US 290 Hwy. Applicant shall construct approximately 1,800 feet of 15-inch gravity wastewater main (minimum 0.5% slope) from the existing 15-inch gravity wastewater main (Project No. 2015-0938; MH #124875) along Williamson Creek, and extend west to the existing 12-inch gravity wastewater main (Project No. 2001-0681; MH #124869) located west of Covered Bridge Dr, as approximately shown on the attached map. The proposed 15-inch gravity wastewater main shall replace the existing 12-inch gravity wastewater main (Project No. 2001-0681) along its path. Applicant shall reconnect all existing wastewater services from the existing 12-inch gravity wastewater main to the proposed 15-inch gravity wastewater main. Applicant shall construct approximately 2,250 feet of 12-inch gravity wastewater main (minimum 1.0% slope) from the existing 8-inch gravity wastewater main (Project No. 2004-0632; MH #200276) located north of Towana Trl, and extend south towards Towana Trl, west along Towana Trl, and then south along Mowinkle Dr to the existing 8-inch gravity wastewater main (Project No. 2009-0589; MH #240017) in Mowinkle Dr, as approximately shown on the attached map. The proposed 12-inch gravity wastewater main shall replace the existing 8-inch gravity wastewater main (Project Nos. 2009-0589 and 2004-0632) along its path. Applicant shall reconnect all existing wastewater services from the existing 8-inch gravity wastewater main to the proposed 12-inch gravity wastewater main. NOTES: 1) Wastewater flow based on engineering calculations received from David J. Hildebrandt, P.E. of LJA Engineering, Inc. on 6/24/2020. 2) The lift station site is conceptually depicted. The lift station shall be located and designed to facilitate future expansion and receive future gravity service from the contributing drainage area. 3) The appropriately sized lift station and force main shall be sized to provide service to the subject tract only; however, the adjacent tract to the west of the subject tract also requires a lift station and force main (Ledgestone SER-4622). It is preferable that only one lift station be constructed to serve the subject tract and Ledgestone (SER-4622).4) Approximately 1,600 feet of the 1,800 feet of 15-inch gravity wastewater main (between MH #124875 – 124870) is also proposed to be constructed by Granada Ridge (SP-2018-0138D; SER-3299). If the Applicant’s project timeline needs these wastewater improvements prior to the completion of them by others, then the design and construction of these improvements are the responsibility of the Applicant. 5) The proposed 1,800 feet of 15-inch gravity wastewater main, 2,250 feet of 12-inch gravity wastewater main, 1,000 feet of 8-inch gravity wastewater main, and a portion of the 6,000 feet of appropriately sized force main is also proposed to be constructed by Ledgestone (SER- 4622). If the Applicant’s project timeline needs these wastewater improvements prior to the completion of them by others, then the design and construction of these improvements are the responsibility of the Applicant. 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) If West Travis County PUA will provide water service, then for wastewater billing purposes, West Travis County PUA must agree to provide winter months (November through February) water readings to the City of Austin within 5 business days of the City’s request. Prior to construction plan approval, an agreement shall be executed between West Travis County PUA, the developer, and the City of Austin regarding this billing arrangement. 6) Public utility mains must meet City of Austin Design and Construction Criteria and must be approved by Austin Water Engineering Review. 7) Proposed public wastewater improvements will be dedicated to the City of Austin for ownership, operation, and maintenance. 8) 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. 9) 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. 10) Approval by the City Council will be required based on Austin City Code § 25-9-35. 960 950 9 3 0 9 4 0 1 0 1 4 0 0 2 0 1 0 0 1 % % 8 9 0 2 0 1 % % % % 990 % 1030 % %% % C % % % % %%% V LANDMARK CONSERVANCY LS %% % C % % % " P C % %% %% % V V % % " P % " P 8 % % %%% % % % % % 8 %% % % %%% 8 %% % %% % %% % % % % % % B21 % %% % % % % % 9 6 0 0 6 9 970 % % % % % % % % % % % % % % 9 % % % % % % % 0 6 0 9 %\ \ \ 3 \ \ % \ \ \ %\ %\ [7L \ %\ \ %\ \ %\ \ \ 1 0 5 0 1 1 2 0 0 1 0 1 1 0 3 0 9 8 0 9 6 0 9 9 0 1 0 6 0 1110 1100 WZ21 1100 1 1 1 0 A22 0 8 9 970 1 0 1 0 1020 1 0 5 0 1 0 0 0 A21 GS RD 1 0 8 0 1 0 5 0 M AS SPRIN 1 0 0 0 1 0 4 0 0 2 0 1 1 0 7 0 1 1 0 0 1 0 9 0 1100 1 1 0 7 0 TH O 0 6 0 1 STAFF PROPOSED APPROXIMATLEY 2,250 FEET OF 12-INCH GRAVITY WASTEWATER MAIN (MINIMUM 1.0% SLOPE) STREA 1 0 9 0 0 1 0 1 M L A U 8 0 0 0 1 1 1 C SIDE D MURMURING CREEK DR 9 9 0 W S H 7 1 % % A N C H U 1050 0 2 0 1 8" P \ \ \ \ \ \ \ \ \ \ % % \ % T L % S % A R \ % \ A R H R % % % % % LE \ %\ % % T D % % % % 0 7 9 \ %\ % % 0 4 0 1 R NIG [7L % %\% SUMMER SKY DR STAFF PROPOSED APPROXIMATELY 1,800 FEET OF 15-INCH GRAVITY WASTEWATER MAIN (MINIMUM 0.5% SLOPE) %%%% % % % % 124869 % %% %% % %%%% % %% %%%%%%%%%%%%%%% R % GE D % % % %% %% %%%% %% % % RID % % 8" PVC D B %%% % % 950 % 0 % %%%%%% %% %%% 7 E 9 ER % %% C OV 8" PVC %%% V % %%% %%%%% 8" P % % %%%% % % % % %% % %% % %%% % %% % %% C % % % % C V V 8" P % 8" P %% % % %% % % % % % NDERBIRD RD %% % 8" C % % %% % % % % % % % % 8" PVC % % % % 8" PVC % 8" PVC % % % % 8" PVC % % % % % % % % R E D L K WIN O 200276 M C V 8" P % C V 8" P % %%% % % % % % % % 8" P 240017 O N % 0 3 9 THU % N D %% % % % % XT % % % % % % % % % % % % % % % % % % C V C % % % R A O R % % % C % % % % % % %% % 930 % % % % % V % % % % % C %% % % 124875 % % % % % % % % % % % % % % % % % % % % % % % % % % \ % % \ % 1 0 7 0 W US 290 HWY %%%%% %% %%%% %%%% \\ [7L %% % % % \ % RIDGEVIEW LS %%%%%% %%%%%%%%% \ \ 1040 0 6 0 1 C L R A L A N D W A N A T R L A20 T O L L A R L N A M C K A T D O H L E R E E N D N T L A R P E T PIT S 1090 %\\ \ % 1070 \ \ \ [7L \\ \ \\ % 0 1 1 1 0 8 0 1 \ \ \ \\ A19 PRIVATE LIFT STATION A R T E R D R 240187 % % %%% \\\% % % \ \ 1080 \ %%%%% %% %%% \\\\ \\\\\\ %%%%% % %%% % %%%% % %% 1 0 7 0 1 0 0 0 % %%%% % 1 0 6 0 % % % % %% % % % % % 0 % % % % % % % 9 1 0 % % 9 2 0 % % 6" P % % C V % 890 % % % !% % %%% 880 !% % % % 9 % % % 8 7 % % % 0 !% % % 0 0 % % % % % % %!% %!%% % % % % % % % % % % % B20 % % % % ABND PRIVATE LIFT STATION [7L % % % AB % % % % % % % %% % 920 % % 0 7 9 % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % 0 94 % B19 9 2 %%%%%%%%%%%%%% %% % 970 0 9 6 0 "J 950 STAFF PROPOSED APPROXIMATELY 6,000 FEET OF APPROPRIATELY SIZED FORCE MAIN A18 9 3 WILLIAMS PIPE LINE COMPANY 0 1 0 2 0 STAFF PROPOSED APPROPRIATELY SIZED LIFT STATION B 9 1 9 0 2 0 980 9 9 0 970 Y O U N 980 G L N 990 9 8 0 E L L A VIS 0 1,000 2,000 4,000 6,000 Feet . W.W. S.E.R. Name: 8921 W. Hwy 290 West W.W. S.E.R. Number: 4796 Utility Development Services Plotted 7/13/2020 9 0 8 % \ \ \ \ \ \ 1 0 % 9 %\ % % % % % % % % STAFF PROPOSED % % % % % %\%\%\%\%\\ %\\ %\\\ %\\%\%\%\%\ \%\ %\%\ APPROXIMATELY %\%\%\ 1,000 FEET OF 8-INCH GRAVITY WASTEWATER MAIN % % % \%%%\ % %%%%% %% % \ 6 12" PVC % 0 \ %\ 9 4 0 %\ %%%% % % %%% % %% %% 920 % % % % PRIVATE LIFT STATION [7L % % % % % % % % VIA RICCODR % % % % % % 0 7 %% 960 % % 9 % % % % N % 9 8 0 % R N L % % %%% % Y D % % %% %%% % O % % % % % % S % T %%% % % D T % A R A E %% N D % % % % B W % % % % % D E % % % !% !% % % % % % % Subject Tract B18 % % % % % % % % % % % BIO \ \ %\ 930 0 1 9 % A T % % % % % % % % % % % % % % % % % % % % %\ %\ % G R A % L T R % 0 1 % . 8 0 8 \ \ \ \ 9 5 0 C " T T % 3 0 9 Y E ! P V ! B A R D % 1 5 ! ! ! ! ! % 100-yr FEMA Floodplain Full-Purpose City Limit 2-Mile ETJ Limited-Purpose City Limit WZ20 1 0 8 0 C I R C L E D R 1 0 3 0 WZ19 1 0 1 0 2 0 0 0 9 6 0 9 9 0 1 0 1 0 1 0 7 0 1 0 6 0 1060 0 5 0 1 R E E T N O T S E G D E L 1 0 4 0 0 2 0 1 970 WZ18 1 0 4 0 1 0 4 0 1 0 3 0 1050 SANDSTONE ST 1 0 3 0 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