E-6 C15-2022-0013 PRESENTATION — original pdf

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3300 BLUE JAY LANE Application for a Variance to LDC 25-2-1176(A)(1) and (A)(4)(b) Dock extension greater than 30 ft. from the Lake Austin shoreline Dock width exceeding 14’ for a shoreline length less than 70’ Case no. C15-2022-0013 Applicant: Janis J. Smith, P.E. E-6/1-PRESENTATIONE-6/2-PRESENTATION3300 & 3302 BLUE JAY LANE NOTE: THE PROPOSED BOAT DOCK MUST COMPLY WITH ALL REQUIREMENTS OF LDC 25-2-1174 (“STRUCTURAL REQUIREMENTS”), AND MUST COMPLY WITH CHAPTER 25-12, ARTICLE 1 (UNIFORM BUILDING CODE) AND THE BUILDING CRITERIA MANUAL. PROPOSED LOWER DECK RAMP 2.9' PROPOSED UPPER DECK RAMP 3.8' 58.1' 26.3' DOCK PLAN VIEW 1" = 10' END OF RAMP ELEV. = 505.5' EXISTING DOCK TO REMAIN LOWER DECK UPPER DECK EXISTING DOCK TO REMAIN EXISTING = PROPOSED LAKESIDE ELEVATION VIEW AS PERMITTED UNDER SP-01-0014 DS EXISTING LANDSCAPE WALL PROPOSED LANDSCAPE WALL OPEN OPEN RAMP TERMINUS AT BULKHEAD ELEV = 505.1' PROPOSED BULKHEAD T.O.W. = 495.0' BOTTOM OF BEAM ELEVATION = 493.8' SIDE ELEVATION 1" = 10' PROPOSED CONDITIONS PLAN/ELEVATION VIEWS OF THE DOCK AT 3302 BLUE JAY LANE BOTTOM OF BEAM ELEVATION = 493.8' EL. 509.3' EL. 504.8' DOCK EL. = 494.8' APPROX. WSEL = 492.8' ' D V P P A I N O S V E R I E T A D . O N 1 2 0 2 / 5 1 / 1 1 FEMA 100-YR FULLY DEVELOPED FLOODPLAIN ELEV = 510.8 FLOODPLAIN IS FULL PURPOSE REMAINDER OF THE PROPERTY IS LIMITED PURPOSE X X X X X X X X X X X X X X X X 8' 0 5 ' 6 0 5 4' 0 5 2' 0 5 INSTALL TREE BOARDS ' 8 9 4 EXISTING = PROPOSED SHORELINE ON 3300 NO BULKHEAD WORK IS PROPOSED ELEV 492.8 PROPOSED 1-STORY, 1-SLIP DOCK SEE DOCK PLAN/ELEVATION VIEWS ON SHEET 4 NO DREDGE PROPOSED LOC LOC LOC LOC FSS FSS FSS FSS LOC FSS 6' 9 4 4' 9 4 LOC LOC XX 431 X X XX 430 X X L O C L O C XX L O C ' 6 0 5 ' 4 0 5 INSTALL TREE BOARDS ' 2 0 5 ' 0 0 5 8' 9 4 ' 6 9 4 X X 429 S S F LOC FSS FSS LOC LOC S S F 3300 56.5' 53.1' EXISTING 5' X 127' WETLAND DISTURBED WETLAND AREAS TO BE MITIGATED LOC FSS C O L 16.4' S S F C O L S S F C O L 10 5 0 10 20 SCALE: 1" = 10 EXISTING SHORELINE LENGTH = 65.3' ALLOWABLE DOCK WIDTH = 14.7' PROPOSED DOCK WIDTH = 16.4' PROPOSED DOCK DEPTH = 56.5' DOCK FOOTPRINT = 582.6 SF 3300 3302 EXISTING SHORELINE LENGTH = 65.2' EXISTING = PROPOSED DOCK WIDTH PROPOSED DOCK DEPTH = 58.0' DOCK FOOTPRINT = 646.9 SF FSS LOC FSS FSS LOC LOC FSS LOC LOC INSTALL FLOATING SILT SCREEN APPROX. 157.1 LF LIMITS OF CONSTRUCTION PHASE 1 CONSTRUCTION L O C LOC LOC LOC 4 9 4 LOC PROPOSED GRADING L O C C S S F O L END PROPOSED BULKHEAD CONSTRUCTION WALL TURNS 90d AND ENDS AT PROPOSED LANDSCAPE WALL APPROX. 10.3 FT. EXISTING LANDSCAPE WALLS TO REMAIN L O C 1 0 5 0 0 5 PROPOSED LANDSCAPE WALL WALL WAS CONSTRUCTED IN 2018 T.O.W. = 500.0 SEE XSECS AND DETAIL THIS SHEET 512 512 0 0 1 1 5 5 K C A B T E S Z Q W C D N A A L 5 7 2 1 5 SEE MITIGATION PLANTING PLAN ON SHEET 5 L O C L O C LOC 0 0 5 L O C L O C LOC 0 9 4 C O L PROPOSED SHORELINE ELEV 492.8 S S F EXISTING SHORELINE PHASE 2 CONSTRUCTION C O L S S F C O L FSS 34.8' 5 9 4 58.0' C O L S S F 3302 PROPOSED ACCESS CONSTRUCTED IN 2018 5 1 1 5 1 1 LOC 507 507 LOC LOC LOC LOC LOC LOC BEGIN PROPOSED LANDSCAPE WALL CONSTRUCTION APPROX. 15.8 LF, T.O.W = 497.0-499.8' INSTALL FLOATING SILT SCREEN APPROX. 76.7 LF PHASE 2 CONSTRUCTION BEGIN PROPOSED BULKHEAD CONSTRUCTION ORIGINALLY PERMITTED AND CONSTRUCTED UNDER EMERGENCY SITE PLAN EXEMPTION DA-2018-0848 APPROX. 53.6 LF, T.O.W = 495.0 SEE XSECS AND DETAIL THIS SHEET C O L S S F C O L S S F LOC 6 9 4 FSS LOC 2 9 4 PROPOSED RAMPS CONSTRUCTED IN 2018 PROPOSED CONDITIONS N I T S U A E K A L 0 9 4 9 8 4 EXISTING DOCK WAS MODIFIED IN 2018 WITH THE ADDITION OF A RAMP TO THE SECOND DECK AND ONE TO THE FIRST DECK THE RAMPS ARE PERMITTED AS PART OF THE DOCK FOOTPRINT EXISTING = PROPOSED DOCK WIDTH SEE PLAN/ELEVATION VIEWS THIS SHEET NO DREDGE PROPOSED LEGEND EXISTING SHORELINE PROPOSED SHORELINE PROPOSED BULKHEAD/LANDSCAPE WALL PHASING PLAN LA SETBACK FEMA 100-YR FLOODPLAIN/BFE TREE PROTECTION FLOATING SILT SCREEN LIMIT OF CONSTRUCTION PROPOSED DOCK XX FSS LOC XX FSS LOC TREE # TREE CRITICAL ROOT ZONE, 1 AND 1 4 CRZ 2 CRZ, 512 510 508 506 504 502 500 498 496 494 492 512 510 508 506 504 502 500 498 496 494 492 512 510 508 506 504 502 500 498 496 494 492 CUT/FILL IN THE FLOODPLAIN 4 9 4 1 0 5 0 0 5 0 0 5 6 9 4 5 4 3 2 1 512 512 0 0 1 1 5 5 2 1 5 5 9 4 5 1 1 5 1 1 507 507 XSEC LOCATIONS 1" = 20' FEMA 100-YR FLOODPLAIN/BFE EXISTING PROFILE PROPOSED PROFILE FILL 16.3 CY EXISTING SHORELINE WSEL = 492.8' CUT 10.6 CY 0 PROPOSED SHORELINE 20 10 XSEC 1 30 512 510 508 506 504 502 500 498 496 494 492 512 510 508 506 504 502 500 498 496 494 492 PROPOSED SHORELINE CUT 26.2 CY WSEL = 492.8' EXISTING PROFILE PROPOSED SHORELINE CUT 23.4 CY WSEL = 492.8' FEMA 100-YR FLOODPLAIN/BFE FEMA 100-YR FLOODPLAIN/BFE EXISTING PROFILE PROPOSED PROFILE FILL 4.5 CY PROPOSED PROFILE FILL 15.9 CY PROPOSED SHORELINE EXISTING PROFILE XSEC 3 EXISTING SHORELINE 0 10 20 30 CUT 25.8 CY WSEL = 492.8' EXISTING SHORELINE 0 10 20 30 XSEC 2 FEMA 100-YR FLOODPLAIN/BFE FEMA 100-YR FLOODPLAIN/BFE PROPOSED PROFILE FILL 15.9 CY CUT 5.2 CY PROPOSED SHORELINE EXISTING SHORELINE WSEL = 492.8' PROPOSED PROFILE EXISTING PROFILE FILL 12.6 CY EXISTING SHORELINE 0 10 20 30 XSEC 4 0 10 XSEC 5 20 30 XSECS AND XSEC LOCATIONS XSEC SCALE 1" = 10' NOTES: PROPOSED 6"X6"X12"LIMESTONE BLOCK LANDSCAPE WALL T.O.W. = 500.0 WALL HEIGHT = 4' FOUNDATION DESIGN UNKNOWN INSTALL TOPSOIL AND PLANTS PER MITIGATION PLANTING PLAN ON SHEET 5 500 498 496 494 492 490 PROPOSED 6"X6"X12" LIMESTONE BLOCK BULKHEAD T.O.W. = 495.0 WALL HEIGHT = 2.5' FOUNDATION DESIGN UNKNOWN SEE EXISTING VS PROPOSED SHORELINE LOCATIONS ON XSECS THIS SHEET INSTALL ROCK RIPRAP TO ELEV 493.8', MIN DIAM = 8" LANDSCAPE WALL AND BULKEAD DETAIL ATTENTION INSPECTOR NOTES: 1. ALL WORK SHALL OCCUR WITHIN THE LIMITS OF CONSTRUCTION AS SHOWN ON THE PLAN. ALL MATERIALS WILL BE TRANSPORTED TO THE SITE FROM WATER. ALL CONSTRUCTION ACTIVITY, INCLUDING STAGING AND SPOIL STORAGE, WILL BE COMPLETED BY WATER. 2. SHORELINE IMPROVEMENTS, INCLUDING GANGWAY ACCESS, ARE AUTHORIZED WITH THIS SITE PLAN. 3. CONTAINERS OF HAZARDOUS MATERIALS, FUEL, OIL, HERBICIDES, INSECTICIDES, FERTILIZERS, OR OTHER POLLUTANTS WILL NOT BE STORED ON DOCKS EXTENDING INTO OR ABOVE LAKE AUSTIN. FOR LA ZONING, PERMANENT IMPROVEMENTS ARE PROHIBITED WITHIN THE SHORELINE SETBACK AREA, EXCEPT FOR RETAINING WALLS, PIERS, WHARVES, BOATHOUSES, MARINAS, OR A DRIVE TO ACCESS THE STRUCTURES [LDC 25-2-551 (B)(2)]. 4. 5. NO WATER OR WASTEWATER UTILITIES ARE PROPOSED WITH THIS DEVELOPMENT. 6. DOCK SHALL BE AT LEAST 66% OPEN. 7. PILINGS SHALL BE 6-5/8" DIAMETER STEEL PIPE. 8. THE PROJECT SITE IS WITHIN THE CITY OF AUSTIN LIMITED PURPOSE BOUNDARIES. 1. COMPLIANCE WITH BUILDING CODE REQUIRED AND IS TO BE REVIEWED FOR COMPLIANCE DURING BUILDING CODE REVIEW. 2. FOR THE BUILDING PERMIT, A SIGNED AND SEALED LETTER SHALL BE SUBMITTED TO THE CITY OF AUSTIN, PER THE LAND DEVELOPMENT CODE, 25-12-3 1612.4, CERTIFYING THAT THE STRUCTURE IS IN ACCORDANCE WITH ASCE 24, FLOOD RESISTANT DESIGN AND CONSTRUCTION. 3. ENVIRONMENTAL INSPECTOR HAS THE AUTHORITY TO ADD AND/OR MODIFY EROSION/SEDIMENTATION CONTROLS ON SITE TO KEEP PROJECT IN COMPLIANCE WITH THE CITY OF AUSTIN RULES AND REGULATIONS. 9 2 7 3 - 4 1 9 - 2 1 5 3 0 7 8 7 s a x e T , n i t s u A d a o R r e v o t s e W 5 0 5 1 8 7 9 6 1 - F r e b m u N n o i t a r t s i g e R s r e e n i g n E l a n o i s s e f o r P f o d r a o B s a x e T C L L , g n i t l u s n o C h t i m S s i n a J E N A L Y A J E U L B 2 0 3 3 & 0 0 3 3 I I I N A L P E T S S N O T D N O C D E S O P O R P D 9 7 2 0 - 1 2 0 2 - P S - E N A L Y A J E U L B 2 0 3 3 & 0 0 3 3 DESIGNED: JJS APPROVED: SCALE: AS SHOWN 3300 & 3302 BLUE JAY LANE DATE: JULY 25, 2021 SHEET of 6 3 3 SP-2021-0279D E-6/3-PRESENTATION2002 PERMITTED DOCK PLAN/ELEVATION VIEWS VS. 2021 DOCK PLAN/ELEVATION VIEWS 2002 PERMITTED SIDE ELEVATION N 2021 BOAT DOCK DECK 2002 PERMITTED BOAT DOCK DECK 2021 SIDE ELEVATION E-6/4-PRESENTATIONDrainage Construction - JAY BAKER 974-2636 DATE: 8/26/02 Acceptance or approval of this application does not constitute a verification of all data, information and calculations supplied by the applicant. The engineer of record is solely responsible for the completeness, accuracy and adequacy of his/her submittal, whether or not the application is reviewed for Code compliance by City engineers. DC 1. CLEARED Signoff: 8/26/02 Environmental - JOHN MCDONALD 974-2294 Comments EV 1 through EV 7 and EV 10 have been cleared. EV 8: The proposed dock’s width exceeds 20% of the entire lake frontage and will need a waiver from the Parks & Recreation Departments Navigation Board. Please contact Randy Scott (974-6737) for scheduling purposes. This comment can be cleared after review by the Navigation Board. EV 9: The proposed dock appears to extend greater than 30’ from the shoreline from the “Side Elevation” on the plans, which will require a waiver from the Parks & Recreation Department’s Navigation Board. Please contact Randy Scott (974-6737) for scheduling purposes. This comment can be cleared after review by the Navigation Board. FYI: Be prepared to get this plan sealed by either a professional architect or engineer before the building permit can be ascertained. A Professional Architect or Engineer’s seal is not required for the site development permit, however, it will most likely be required for the building permit. THIS SITE PLAN CANNOT BE APPROVED UNTIL IT IS PRESENTED AND APPROVED FOR WAIVERS FROM THE PARKS & RECREATION BOARD. PLEASE CONTACT RANDY SCOTT (974-6737) FOR SCHEDULING PROCEDURES. E-6/5-PRESENTATIONFLOATING DOCK LOCATION PRIOR TO RECONSTRUCTION FIXED DOCK LOCATION CONSTRUCTED IN 2017 E-6/6-PRESENTATIONPHOTO OF ROCK LAKEBED E-6/7-PRESENTATIONA Review of Lake Austin Sediment Quality, 1987-2009 Mary Gilroy and Martha Turner Environmental Resource Management, Watershed Protection Department City of Austin SR-10-14. September 2010 Conclusions The following conclusions were derived from the analyses of Lake Austin sediment data: • Spatially, concentrations of parameters generally increased with downstream location, as the most downstream site, Tom Miller had the significantly highest mean for most parameters showing spatial differences. This is to be expected, as there is increasing, and more long-established, residential development towards the downstream end of the lake. In addition, sediment (and associated contaminants) is transported downstream during high flow events and deposited in deeper, slower water near the dam, so the most downstream site becomes the repository for contaminants. • The upper sites, Selma Hughes and Emma Long, were not significantly different from each other, and always had means well below the other two more downstream sites. This could be in part due to their location in the upper, less developed portion of the watershed, but also a function of the sediment characteristics. Both these sites were dominated by sand, with very little clay or silt, providing little substrate for contaminant adherence. In addition, the upper end of the watershed typically experiences more scouring flows during flood events, as extremely high velocity water moves in from the upstream dam, and less sediment was available at these sites during many sampling events. E-6/8-PRESENTATION