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picture1_Excel Spreadsheet Calculations 46116 | Charlotte Bmp Design


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File: Excel Spreadsheet Calculations 46116 | Charlotte Bmp Design
sheet 1 basic info bmp sizing data ld xxxx required user input data xxxx calculations post developed basin data predeveloped basin data drainage area 1000 ac drainage area 1000 ac ...

icon picture XLSX Filetype Excel XLSX | Posted on 17 Aug 2022 | 3 years ago
Partial file snippet.
Sheet 1: Basic info
BMP Sizing Data





ld













XX.XX Required user input data








XX.XX Calculations



















Post Developed Basin Data




Pre-Developed Basin Data



Drainage Area = 1.000 ac


Drainage Area = 1.000 ac

Impervious % (I)= 85.000 %


Impervious % (I)= 50.000 %

Impervious acres = 0.850 ac


Impervious acres = 0.500 ac

Curve Number (CN) = 80.000



Curve Number (CN) = 65.000


Tc = 7.000 minutes = 0.117 hours
Tc = 19.000 minutes = 0.317 hours
T lag = 4.200 minutes = 0.070 hours
T lag = 11.400 minutes = 0.190 hours












































Water Quality Volume Calculations


Channel Protection Volume Calculations





Rv = 0.05+0.009(I) = 0.815

Q = (P-0.2S)^2/(P+0.8S) = 0.945 inches



WQv = 1.0RvA/12 = 0.068 ac-ft
S = 1000/CN-10 = 2.500




WQv = 1.0Rv = 0.815 inches
CPv = 0.079 acre-ft



Modified CN = 98.260









Sheet 2: Bioretention
4.1.7 Design Procedure Form











































Design Procedure Form: Bioretention
















Detention time Detention time Media



















Days hours + 3 hrs Depth

BIORETENTION FEASIBILITY



NOTES:









1 Optimal 1.3 34.2 4

1. Is the use of Bioretention appropriate?













2 Standard 1 27 2























2. Confirm other design criteria and applicability.










































Pollutant Removal Effectiveness Required



Optimal




Dt




















1.3 34.2 4






PRELIMINARY HYDROLOGIC CALCULATIONS










































3 Compute site hydrologic input parameters




















Development Conditions



Pre-developed
Post-developed













Area



1 acres 1 acres












CN (SCS curve number)



65
80













Adjusted CN (curve number adjusted for 1-inch storm)





98.26













Time of concentration



19 min 7 min

















0.32 hours 0.12 hours

































4 Compute,WQv water quality volume requirements




















Compute Runoff Coefficient, Rv



Rv = 0.82














Compute WQv Volume requirements



WQv = 0.07 acre-ft


































5 Compute WQp peak flow using SCS



WQp =
cfs













Compute modified SCS curve number



CN = 98.26



































6 Compute CPv




















Compute S (maximum retention)



S = 2.50














Compute 1-yr, 24-hr total rainfall depth



Rainfall Depth = 2.58 inches













Compute Qd (runoff volume)



Qd = 0.94 inches













Compute CPv (chnnnel protection volume)



CPv = 0.08 acre-ft


3429.00262008734






























7 Size Flow Diversion Structure










































BIORETENTION AREA DESIGN









































8 Pretreatment facility type and design parameters
































Size bioretention ponding area to contain Water Quality Volume







9 Determine Area of bioretention ponding/filter area



Af = 3690.9 ft2



2958.45 ft2



















Size using Darcy's equation using hf=0.5







10 Set design eleveations and dimensions of facility



Length =
ft



3690.9 ft2












Width =
ft


















Top Elevation =
ft


































11 Develop stage-discharge and stage storage























Elevation Area (ft2) Volume (ft3) Acc. Vol (ft3) Q (cfs)



























































































































































































































12 Route flows through bioretention area. Resize the footprint area, if desired. Step is most effective for facilities with flow diverters. Ensure detention time requirements and maximum ponding depth requirements are met.




























































































13 Design conveyance to facility









































14 Size underdrain system



Length =
ft


































15 Design emergency overflow



Length of Weir (if used) =

ft

































16 Prepare vegetation and landscaping plan



Notes:




































































































































































































































































































































































































































































































































































































































































































































































Sheet 3: Wetpond
4.2.7 Design Procedure Form











































Design Procedure Form: Wet pond
















Detention time Detention time



















Days hours + 3 hrs WQv/PPv

WET POND FEASIBILITY



NOTES:









1 Optimal 4 99 0.3

1 Is the use of a wet pond appropriate?













2 Standard 2 51 0.6

















3 TSS-only 4 99 0.4

2 Confirm other design criteria and applicability.










































Pollutant Removal Effectiveness Required



Optimal




Dt WQv/PPv



















99 0.3







PRELIMINARY HYDROLOGIC CALCULATIONS










































3 Compute site hydrologic input parameters




















Development Conditions



Pre-developed
Post-developed













Area



1 acres 1 acres












CN (SCS curve number)



65
80













Adjusted CN (curve number adjusted for 1-inch storm)





98.26













Time of concentration



19 min 7 min

















0.32 hours 0.12 hours











4 Compute,WQv water quality volume requirements




















Compute Runoff Coefficient, Rv



Rv = 0.82














Compute WQv Volume requirements



WQv = 0.068 acre-ft


































5 Compute WQp peak flow using SCS



WQp =
cfs













Compute modified SCS curve number



CN = 98.26



































6 Compute CPv




















Compute S (maximum retention)



S = 2.50














Compute 1-yr, 24-hr total rainfall depth



Rainfall Depth = 2.58 inches













Compute Qd (runoff volume)



Qd = 0.94 inches













Compute CPv (chnnnel protection volume)



CPv = 0.08 acre-ft













Estimate tc (time of concentration)



tc = 0.12 hours



































Compute approximate storage volume



Storage volume = XXXXXX acre-ft


































7 Compute release rates




















Compute WQv release rate



Release Rate = 0.008 cfs













Compute CPv release rate



Release Rate = 0.016 cfs


60 hours - time for CPv to be released




















must be between 60-132 hours








STORM WATER DETENTION BASIN DESIGN









































8. Pretreatment volume




















Volpre = Acres of Impervious Area(0.2”)(1‟/12”)



WQpre = 0.014 acre-ft


































9. Compute Permanent Pool Volume and




















Water Quality Extended Volume




















Compute WQv/PPv



WQv/PPv = 0.3














Compute PPv



PPv = 0.23 acre-ft













Size extended detention – pool volume is greater




















of WQv or CPv



ED Pool Volume = 0.08 acre-ft


































10. Conduction grading and determine storage available




Prepare an elevation-storage table and curve using















for permanent pool (and WQv-ED volume if applicable)



the average area method for computing volumes.







































































































Elevation Area Average Area Depth
Incremental Volume Cumulative Volume Volume above Permanent Pool













MSL (acres) (acres) (ft)
(acre-ft) (acre-ft) (acre-ft)








































































































































































































































12. WQv Orifice Computations




















Average ED release rate



Release Rate =
cfs













Average head, h = (ED elev. – Permanent pool elev.) / 2



h =
ft













Area of orifice from orifice equation: Q = CA(2gh)0.5



A =
ft2


















Diameter =
in












13. Compute release rate for CPv control and




















Establish CPv elevation



WSEL =
ft













Release rate



Release Rate =
cfs













Average head h = CPv elev. – Permanent pool elev.) / 2



h =
ft













Area or orifice from orifice equation: Q = CA(2gh)0.5



A =
ft2


















Diameter =
in












14. Calculate Qp release rate and water surface elevation














































Set up a stage-storage-discharge relationships.






































Peak stage for (WQv), the 1-inch, 6-hour storm



Peak Stage =
ft













Peak stage for (CPv), the 1-yr, 24-hour storm



Peak State =
ft













Peak Q10 – Undeveloped



Q10-undev =
cfs













Peak Q10 – Developed



Q10-dev =
cfs













Peak Q25 – Undeveloped



Q25-undev =
cfs













Peak Q25 – Developed



Q25-dev =
cfs













Size emergency spillway, calculate 50-year WSEL



WSEL50 =
ft













and set top of embankment elevation



Embankment Elevation =
ft
























































15. Investigate potential wet detention basin hazard


Notes:
















classification









































16. Assess maintenance access and safety features.









































17. Attach landscaping plan































































The words contained in this file might help you see if this file matches what you are looking for:

...Sheet basic info bmp sizing data ld xxxx required user input calculations post developed basin predeveloped drainage area ac impervious i acres curve number cn tc minutes hours t lag water quality volume channel protection rv q ps inches wqv rva acft s cpv acreft modified bioretention design procedure form detention time media days hrs depth feasibility notes optimal is the use of appropriate standard confirm other criteria and applicability pollutant removal effectiveness dt preliminary hydrologic compute site parameters development conditions postdeveloped scs adjusted for inch storm concentration min requirements runoff coefficient wqp peak flow using cfs maximum retention yr hr total rainfall qd chnnnel size diversion structure pretreatment facility type ponding to contain determine pondingfilter af ft darcy equation hf set eleveations dimensions length width top elevation develop stagedischarge stage storage acc vol route flows through resize footprint if desired step most effecti...

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