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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: Van Dine Plaza
Plan preparer: Mike Myers, Dominion Engineering [172 S. Pantops Drive, Charlottesville, VA
22911, mmy ers(a)dominioneng com]
Owner or rep.: Auto LLC [1389 Richmond Road, Charlottesville VA 22901]
Plan received date: 29 April 2014
Date of comments: 27 May 2014
Reviewer: John Anderson
A. Stormwater Management Plan (WP0201400039)
1. Include Albemarle County General Stormwater Notes.
2. Provide Stormwater Narrative.
3. Identify critical slopes.
4. Include inlet structure detail (DI -313, DI -3C).
5. Revise plan date (title sheet references topography field verified in April 2014, yet plans are dated March
19, 2009).
6. Review and revise (if necessary) Redi -rock Gravity Wall design to accommodate vehicle surcharge (sheet
C4); this wall is required for SWM facilities and other infrastructure.
7. Use impervious cover computations to calculate %RR for developed area. Evaluate %RR against SWM
water quality requirements and proposed design.
8. Provide SCS routing calculations, to include: storage input data for underground detention system; outfall
control structures; inflow hydrographs; and routing method - storage- indication. Furnish a profile for the
6'DIA underground storage system that shows WSE for 2 -yr and 10 -yr storm events.
9. Supplement General Construction Notes for Stormwater Management, sheet C4: Provide details for 6' DIA
CMP underground system: include bedding/backfill material, depth, compaction, lift, and any other details
necessary to properly install this system.
10. Revise Str -2 detail, sheet C5; provide scale drawing of outlet structure section detail.
11. Revise OP detail, sheet C5, consistent with stone apron length/width shown in OP detail, ESC Plan, sheet
E4.
12. Review pipe lengths on Storm Sewer Profile, Str 1 - >7, sheet C5, and sheet C4 (plan view); lengths are
inconsistent. Confirm that total storage length is 300 -ft, 6' DIA pipe.
13. Furnish Filterra (Mfr) design chart: drainage area vs. unit dimensions.
Engineering Review Comments
Page 2 of 2
14. Relocate Filterra -173; it must be immediately adjacent to a storm drain structure.
15. Label existing edge of pavement, sheet C4.
16. Revise design of 23'— 15" HDPE to avoid slope > 16 %.
17. Please confirm that 12" pine, 15" poplar, and 15" maple (sheet C4) remain; photos (6- May -14) and aerial
photos indicate change between 2009 and 2014. Contact Albemarle County Zoning Division for questions
relating to Approved Site Plan, Conservation Plan (tree preservation requirements), and possible mitigation
requirements. If trees scheduled to remain have been removed, revise pre - development drainage area map,
Sheet D2, and revise location of tree protection fence to reflect existing conditions.
18. Sheet Dl: relocate Filterra DA data (3, 4, 4A, 413, 6, 7) to table, or drawing margins. Uncover underlying
details. For 0.46 Ac. ST -7 DA, show how runoff above the parking lot (508' contour, and falling) reaches
STR -7. It appears that a portion of runoff may not reach Filterra F7 as indicated.
B. Erosion Control Plan (WPO201400030)
1. In Phase 1, extend temporary diversion dike shown on sheet E2, upslope, toward Rio Road.
2. In Phase 2, provide sediment trap at NE corner of site to intercept flow from 20 -ft fall in grade, sheet E3.
3. Revise plan date (title sheet references topography field verified in April 2014, yet plans are dated March
19, 2009).
4. Provide CIP and OP for existing 3 -24" HDPE culvert in addition to SF.
5. Tree protection, sheet E3, may be unnecessary if 12" pine, 15" poplar, and 15" maple were removed.
6. SF near 3 -24" HDPE appears to conflict with grade. Ensure SF will not prevent grading to final contour.
7. Sediment trap, sheet E4: given embankment height, embankment width (3') is insufficient. Embankment
height of 6 -ft. exceeds 5 -ft maximum. Please revise.
8. Furnish SAF between LOD and sidewalk, Rio Road, and commercial property to SE.
File: WPO201400039 -Van Dine Plaza- 052714