HomeMy WebLinkAboutWPO201900039 Temporary Sediment Basin Design Data Sheet 2020-06-17TEMPORARY SEDIMENT BASIN DESIGN DATA SHEET
(with or without emergency spillway)
Project Hillcrest Tasting and Venue
Basin # ADD.
Total Area Draining to Basin 216,726 sq.ft.
5.03 acres
Basin Volume Design
Wet Storage
Minimium Required Volume = 67 cu. yds. x Total Drainage Area (acres)
67 cu. yds. x 5.03 acres = 337.01 cu. yds.
9099 cu.ft.
Available basin volume = 337.01 cu.yds.
at elevation 1074.45 ft (from Sed Basin Calcs stage/storage table)
Orifice Invert Elevation = wet storage surface elevation
Elevation = 1074.45 ft
Available volume beore cleanout required.
33 cu.yds. x 5.03 acres = 165.99 cu.yds.
4482 cu.ft.
Elevation corresponding to sediment cleanout level
at elevation 1073 (from Sed Basin Calcs stage/storage table)
Distance from invert of the dewatering orifice to clean out level
1.45 ft (min 1.0 ft)
Dry Storage
Minimium Required Volume = 67 cu. yds. x Total Drainage Area (acres)
67 cu. yds. x 5.03 acres = 334.50 cu. yds.
9031 cu.ft.
Total available basin volume at crest of riser (Min = 134 cu.yds./acre total drainage)
674 cu.yds.
18199 cu.ft.
Riser Crest Elev. 1076.70 ft (from Sed Basin Calcs stage/storage table)
Dewatering orifice
Storage
Flow Rate
Min. Orifice Dia
Design Orifice Dia
Flexible Tubing Dia
9031.4 cu.ft
0.42 cu.ft/s
3.00 in
3.00 in
6.00 in
(Dewatering within 6 hours)
Preliminary Design Elevations
Riser Crest Elev.
1076.70 ft (from Sed Basin Calcs stage/storage table)
Top of Dam
1080 ft
Design High Water
25yr-24hr storm
1077.79 ft (from Sed Basin Calcs stage/storage table)
Upstream Toe Elev.
1080.00 ft
Basin Shape (at Normal Pool)
Runoff
Length of Flow L =
2.86 L 100
Effective Width We
Are baffles required?
If > 2, baffles are not required No A 3500
If < 2, baffles are required
Q2 9.00 cfs (from Sed Basin Hydrograph, routed)
Q25 21.57 cfs (from Sed Basin Hydrograph, routed)
Principal Spillway Design
With emergency spillway, required spillway capacity Qp = Q2 = n/a cfs
Without emergency spillway, required spillway capacity Qp = Q25 = 21.57 cfs
With Emergency spillway:
Assumed available head (h) = n/a ft
h = Crest of Emergency Spillway - Riser Crest
Without Emergency Spillway
Assumed available head (h) = 1.09 ft
h = Design High Water Elevation - Riser Crest
Riser Design
Riser Diameter (Dr) = 36 in (from Sed Basin Calcs)
Actual head (h) = 1.09 ft
Barrel Design
Barrel Length (1) = 60 ft
Barrel Invert upstream = 1070.4 ft
Barrel Invert downstream = 1069.8 ft
Head on Barrel through
7.39
embakment ft
Barrel Diameter 18 in
Trash rack & Diameter 54 in (from VESCH Table 3.14-D)
Antivortex device Height 17 in (from VESCH Table 3.14-D)
ft
ft
Emergency Spillway Design
Required spillway capacity Qe = Q25 - QP = (NOT APPLICABLE, 2'+ FREEBOARD EXISTS)
Bottom Width (b) _
Exit channel slope (s)
Exit channel min. lenth (x)
Anti -Seep Collar Design
cfs
ft From table 3.14-C
ft/ft
ft
Depth of water at principal spillway crest (Y) _ (NOT APPLICABLE, SILTY -CLAY SOILS EXIST,
-3.30 ft <10' EMBANKMENT)
Slope of upstream face of embankment (Z) _
4 :1
Slope of Principal Spillway barrel (Sb) _
0.12 ft/ft
Length of barrel in saturated zone (Ls) _
-50.8 ft
Number of collars required
Dimmensions
Final Design Elevations
Top of Dam=
Design High Water
Emergency Spillway Crest
Principal Spillway Crest
Dewatering Orifice Inv.
Cleanout Elevation
Basin Bottom Elevation
3
7.25 ft
1080.00
1077.79
n/a
1076.70
1074.45
1073.00
1070.50 (at riser base)
From Plate 3.14-12