FLOOD11632 ‎(2)‎

• County: Costilla
• Community: Costilla County
• Stream Name: Rito Seco
• Basin: Rio Grande
• Title: Approximate Floodplain - Rito Seco
• Date: 1/5/2007
• Prepared For: Costilla County
• Prepared By: HDR Engineering, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

costilla.rep
Maximum allowable submerge~nce for weir fl ow = .95
Elevation at which weir flow begins =
Energy head used in spillway design =
spillway hei ght used in desig n
weir crest shape = Broad Crested
Number of Bridge Coefficient sets = 1
Low Flow Methods and Data
Energy
Selected Low Flow Methods = H ighest Energy Answer
High Flaw Method
Energy only
Additional Bridge Parameters
Add Friction component to Momentum
Do not add weight comp onent to Momentum
Class B flow critical depth computations use critical depth
inside the bridge at the upstream end
Criteria to check for pressure flow = upstream energy grade line
BRIDGE OUTPUT Profile #2-Yea r
E.G. U5. (ft) 8012.61 Element Inside BR US Inside BR DS
w.s. U5. (ft) 8012.56 E.G. Elev (ft) 8012.61 8012.57
Q Total (cfs) 104.00 w.s. Elev (ft) 8012.56 8012.51
q Bridge (cfs) 104.00 Crit w.s. (ft) 8011.66 8011.66
Q weir (cfs) Max Chl Dpth (ft) 1.56 1.51
weir sta Lft (ft) vel Total ft/s) 1.91 1.97
weir Sta Rgt (ft) Flow Area ~sq ft) 54.51 52.84
weir submerg Froude # Chl 0.27 0.28
Weir Max Depth (ft) Specif Force (cu ft;) 48.62 46.24
Min E1 weir Flow (ft) 8011.01 Hydr Depth (ft) 1.56 1.51
Min E1 Prs (ft) 8015.10 w.P. Total (ft) 36.56 36.51
Delta EG ft 0.04 Conv. Total (cfs) 2643.3 2511.5
Delta w5 ft 0.05 Top Width (ft) 35.00 35.00
BR Open Area (s ft) 143.50 Frctn Loss (ft) 0.04 0.00
BR open vel (ft9s) 1.97 C& E ~oss (ft) 0.00 0.00
Coef of Q Shear Total (lb/sq ft) 0.14 0.15
Br Sel Method Ene rgy only Power Total (lb/ft s) 0.27 0.30
BRIDGE OUTPUT PrOfile #5-vear
E.G. U5. (ft) 8013.11 Element Inside BR US Inside BR DS
w.5. U5. (ft) 8013.01 E.G. Elev (ft) 8013.11 8013.05
Q Total (cfs) 183.00 w.s. Elev ft 8013.01 8012.94
Q Bridge (cfs) 183.00 Crit w.5. ~ft3 8011.96 8011.96
Q weir (cfs) Max Chl Dpth (ft) 2.01 1.94
weir sta Lft (ft) vel Total (ft/s) 2.60 2.70
weir Sta Rgt (ft) Flow Area (sq ft) 70.27 67.90
weir Submerg Froude # Chl 0.32 0.34
weir Max Depth (ft) specif Force (cu ft) 85.35 81.17
Min El weir Flow (ft) 8011.01 Hydr Depth (ft) 2.01 1.94
Min E1 Prs (ft) 8015.10 W.P. Total (ft) 37.01 36.94
Delta EG (ft) 0.06 Conv. Total (cfs) 4002.9 3784.5
Delta ws (ft) 0.07 Top width (ft) 35.00 35.00
BR Open Area (s ft)
BR o
v
l (ft9
) 143.50
2
70 Frctn Loss (ft)
&
f 0.06 0.00
pen
e
s
Coef of Q . c
E ~oss (
t)
shear Total lb/sq ft) 0.00
0.25 0.00
0.27
Br Sel Method Energy only Power Total ~lb/ft s) 0.65 0.72
BRIDGE OvTPUT Profile #10-Year
E.G. U5. (ft) 8013.46 Element Inside BR US Inside BR DS
w.5. U5. (ft 8013.30 E.G. Elev ft 8013.46 8013.38
Q Total (cfs 254.00 w.s. Elev ~ft~ 8013.30 8013.21
Q Bridge (cfs) 254.00 Crit w.s. (ft) 8012.18 8012.18
Q weir (cfs) Max Chl Dpth {ft) 2.30 2.21
weir sta Lft (ft) vel Total (ft/s) 3.15 3.28
weir Sta Rgt (ft) Flow Area (sq ft) 80.56 77.47
weir Submerg Froude # chl 0.37 0.39
weir Max Depth (ft) specif Force (cu ft} 117.58 111.59
Min E1 Weir Flow (ft) 8011.01 Hydr Depth (ft) 2.30 2.21
Min E1 Prs (ft) 8015.10 W.P. Total (ft) 37.30 37.21
Delta EG (ft) 0.08 Conv. Total (cfs) 5000.1 4691.6
Delta ws (ft) 0.09 Top Width (ft) 35.00 35.00
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