SW1240401_Design Calculations_20240815

STORMWATER/DETENTION FACILITIES
(STORMTECH CHAMBER SYSTEM)
CALCULATION MANUAL
MARS HILL UNIVERSITY STUDENT
CENTER
MARS HILL, NORTH CAROLINA
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Davis CivilSolutions, PA
REVISED AUGUST 13, 2024
20166

Mars Hill University Student Center, 1-in Rainfall (Pre-Const) Type II 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1 S: Runoff
Mars Hill University Student Center., 1-n Rainfall (Pre-Construction)
[49] Hint: Tc<2dt may require smaller dt
[45] Hint: Runoff=Zero
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Depth= 0.00"
Routed to nonexistent node 1 P
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-50.00 hrs, dt= 0.05 hrs
Type II 24-hr Rainfall=1.00"
Area (ac) CN Description
0.233 61 >75% Grass cover, Good, HSG B
0.099 39 >75% Grass cover, Good, HSG A
0.332 54 Weighted Average
0.332 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.7 75 0.0200 0.22 Lag/CN Method,
Subcatchment 1S: Runoff
Hydrograph
D Runoff
Type II 24-hr
Rainfall=1 .00"
Runoff Area=0.332 ac
Runoff Volume=0 cf
Runoff Depth=0.00"
Flow Length=75'
Slope=0.0200 '/'
Tc=5.7 m i n
CN=54
0 W
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Time (hours)

Mars Hill University Student Center, 1-in Rainfall (Pre-Const) Type II 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: Runoff
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 26.00 1.00 0.00 0.00
0.50 0.01 0.00 0.00 26.50 1.00 0.00 0.00
1.00 0.01 0.00 0.00 27.00 1.00 0.00 0.00
1.50 0.02 0.00 0.00 27.50 1.00 0.00 0.00
2.00 0.02 0.00 0.00 28.00 1.00 0.00 0.00
2.50 0.03 0.00 0.00 28.50 1.00 0.00 0.00
3.00 0.03 0.00 0.00 29.00 1.00 0.00 0.00
3.50 0.04 0.00 0.00 29.50 1.00 0.00 0.00
4.00 0.05 0.00 0.00 30.00 1.00 0.00 0.00
4.50 0.06 0.00 0.00 30.50 1.00 0.00 0.00
5.00 0.06 0.00 0.00 31.00 1.00 0.00 0.00
5.50 0.07 0.00 0.00 31.50 1.00 0.00 0.00
6.00 0.08 0.00 0.00 32.00 1.00 0.00 0.00
6.50 0.09 0.00 0.00 32.50 1.00 0.00 0.00
7.00 0.10 0.00 0.00 33.00 1.00 0.00 0.00
7.50 0.11 0.00 0.00 33.50 1.00 0.00 0.00
8.00 0.12 0.00 0.00 34.00 1.00 0.00 0.00
8.50 0.13 0.00 0.00 34.50 1.00 0.00 0.00
9.00 0.15 0.00 0.00 35.00 1.00 0.00 0.00
9.50 0.16 0.00 0.00 35.50 1.00 0.00 0.00
10.00 0.18 0.00 0.00 36.00 1.00 0.00 0.00
10.50 0.20 0.00 0.00 36.50 1.00 0.00 0.00
11.00 0.24 0.00 0.00 37.00 1.00 0.00 0.00
11.50 0.28 0.00 0.00 37.50 1.00 0.00 0.00
12.00 0.66 0.00 0.00 38.00 1.00 0.00 0.00
12.50 0.73 0.00 0.00 38.50 1.00 0.00 0.00
13.00 0.77 0.00 0.00 39.00 1.00 0.00 0.00
13.50 0.80 0.00 0.00 39.50 1.00 0.00 0.00
14.00 0.82 0.00 0.00 40.00 1.00 0.00 0.00
14.50 0.84 0.00 0.00 40.50 1.00 0.00 0.00
15.00 0.85 0.00 0.00 41.00 1.00 0.00 0.00
15.50 0.87 0.00 0.00 41.50 1.00 0.00 0.00
16.00 0.88 0.00 0.00 42.00 1.00 0.00 0.00
16.50 0.89 0.00 0.00 42.50 1.00 0.00 0.00
17.00 0.90 0.00 0.00 43.00 1.00 0.00 0.00
17.50 0.91 0.00 0.00 43.50 1.00 0.00 0.00
18.00 0.92 0.00 0.00 44.00 1.00 0.00 0.00
18.50 0.93 0.00 0.00 44.50 1.00 0.00 0.00
19.00 0.94 0.00 0.00 45.00 1.00 0.00 0.00
19.50 0.95 0.00 0.00 45.50 1.00 0.00 0.00
20.00 0.95 0.00 0.00 46.00 1.00 0.00 0.00
20.50 0.96 0.00 0.00 46.50 1.00 0.00 0.00
21.00 0.96 0.00 0.00 47.00 1.00 0.00 0.00
21.50 0.97 0.00 0.00 47.50 1.00 0.00 0.00
22.00 0.98 0.00 0.00 48.00 1.00 0.00 0.00
22.50 0.98 0.00 0.00 48.50 1.00 0.00 0.00
23.00 0.99 0.00 0.00 49.00 1.00 0.00 0.00
23.50 0.99 0.00 0.00 49.50 1.00 0.00 0.00
24.00 1.00 0.00 0.00 50.00 1.00 0.00 0.00
24.50 1.00 0.00 0.00
25.00 1.00 0.00 0.00
25.50 1.00 0.00 0.00

Mars Hill University Student Center, 1-in Rainfall Detention (P Type 1124-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1 S: Runoff
Mars Hill University Student Center, 1-in Rainfall, (Post-Construction)
[49] Hint: Tc<2dt may require smaller dt
Runoff = 0.00 cfs @ 13.41 hrs, Volume= 28 cf, Depth= 0.02"
Routed to Pond 1 P : StormTech Detention
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type II 24-hr Rainfall=1.00"
Area (ac) CN Description
* 0.166 98 Pavements, Sidewalks, Roofs
0.083 61 >75% Grass cover, Good, HSG B
0.083 39 >75% Grass cover, Good, HSG A
0.332 74 Weighted Average
0.166 50.00% Pervious Area
0.166 50.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
3.4 75 0.0200 0.37 Lag/CN Method,
Subcatchment 1 S: Runoff
Hydrograph
/ I I I U I 1 1 1 1 1 1 1 1 I
1 L J 1 1 L J 1 L L J 1 1 L I I J 1 L L
1
I I I I II I I I I I IL
I Q Runoff
0.001: J 1 1 L J 1 1 L I 1 1 L J 1 1 L I ! -_ L_L_
O.00Cf_. 1 I I I I I I I I I
0.001: Jr J 1 1 L 1 1 L J L_1_
0.001- ; ;1 Type II 24-hrL
0.00,-; Rainfall=1-.00' - -
I 1 1
0.001 1
0.001` �1 1
1 Runoff Area=0.332 ac
T _ __ _, 1 1 r 1 r
0.001 r r r I I I ' -r Runoff Volume=28 cf
- - -- - r r 1
0.001
- -I-' --7-r -r I -r r -I Y t
N =
13 0.000- 1 -: -�-- --- -r- -------1-;-t-� Runoff Depth=0.02
1 I 1 I
0 0.000= + + Flow Length-75,
1 1 -
0.000= 1 L J L Slope=0.0200 '/'
1
0.000- J 1 _L _1 L J 1 1 L J 1
0.000: J 1 -1 L J 1 1 L J 1
- Tc=3.4 min
I I I I
0.000 1 I J ' CN=74
1 1 I 1
0.000 1
1 1 1 I
I 1 1 1 I 1 1 1
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)

Mars Hill University Student Center, 1-in Rainfall Detention (P Type 11 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: Runoff
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 1.00 0.02 0.00
1.00 0.01 0.00 0.00 53.00 1.00 0.02 0.00
2.00 0.02 0.00 0.00 54.00 1.00 0.02 0.00
3.00 0.03 0.00 0.00 55.00 1.00 0.02 0.00
4.00 0.05 0.00 0.00 56.00 1.00 0.02 0.00
5.00 0.06 0.00 0.00 57.00 1.00 0.02 0.00
6.00 0.08 0.00 0.00 58.00 1.00 0.02 0.00
7.00 0.10 0.00 0.00 59.00 1.00 0.02 0.00
8.00 0.12 0.00 0.00 60.00 1.00 0.02 0.00
9.00 0.15 0.00 0.00 61.00 1.00 0.02 0.00
10.00 0.18 0.00 0.00 62.00 1.00 0.02 0.00
11.00 0.24 0.00 0.00 63.00 1.00 0.02 0.00
12.00 0.66 0.00 0.00 64.00 1.00 0.02 0.00
13.00 0.77 0.00 0.00 65.00 1.00 0.02 0.00
14.00 0.82 0.00 0.00 66.00 1.00 0.02 0.00
15.00 0.85 0.01 0.00 67.00 1.00 0.02 0.00
16.00 0.88 0.01 0.00 68.00 1.00 0.02 0.00
17.00 0.90 0.01 0.00 69.00 1.00 0.02 0.00
18.00 0.92 0.01 0.00 70.00 1.00 0.02 0.00
19.00 0.94 0.01 0.00 71.00 1.00 0.02 0.00
20.00 0.95 0.02 0.00 72.00 1.00 0.02 0.00
21.00 0.96 0.02 0.00
22.00 0.98 0.02 0.00
23.00 0.99 0.02 0.00
24.00 1.00 0.02 0.00
25.00 1.00 0.02 0.00
26.00 1.00 0.02 0.00
27.00 1.00 0.02 0.00
28.00 1.00 0.02 0.00
29.00 1.00 0.02 0.00
30.00 1.00 0.02 0.00
31.00 1.00 0.02 0.00
32.00 1.00 0.02 0.00
33.00 1.00 0.02 0.00
34.00 1.00 0.02 0.00
35.00 1.00 0.02 0.00
36.00 1.00 0.02 0.00
37.00 1.00 0.02 0.00
38.00 1.00 0.02 0.00
39.00 1.00 0.02 0.00
40.00 1.00 0.02 0.00
41.00 1.00 0.02 0.00
42.00 1.00 0.02 0.00
43.00 1.00 0.02 0.00
44.00 1.00 0.02 0.00
45.00 1.00 0.02 0.00
46.00 1.00 0.02 0.00
47.00 1.00 0.02 0.00
48.00 1.00 0.02 0.00
49.00 1.00 0.02 0.00
50.00 1.00 0.02 0.00
51.00 1.00 0.02 0.00

Mars Hill University Student Center, 1-in Rainfall Detention (P Type 11 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 3
Summary for Pond 1 P: StormTech Detention
Detention Facility
Inflow Area = 14,462 sf, 50.00% Impervious, Inflow Depth = 0.02"
Inflow = 0.00 cfs @ 13.41 hrs, Volume= 28 cf
Outflow = 0.00 cfs @ 19.89 hrs, Volume= 28 cf, Atten= 32%, Lag= 388.9 min
Discarded = 0.00 cfs @ 19.89 hrs, Volume= 28 cf
Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf
Routed to nonexistent node 1 R
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Peak Elev= 0.01' @ 19.89 hrs Surf.Area= 2,650 sf Storage= 9 cf
Plug-Flow detention time= 264.3 min calculated for 28 cf (100% of inflow)
Center-of-Mass det. time= 264.0 min ( 1,330.6 - 1,066.6 )
Volume Invert Avail.Storage Storage Description
#1A 0.00' 5,079 cf 77.08'W x 34.38'L x 5.50'H Field A
14,576 cf Overall - 1,878 cf Embedded = 12,697 cf x 40.0% Voids
#2A 0.75' 1,878 cf ADS StormTech MC-3500 d+Cap x 16 Inside#1
Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf
Overall Size= 77.0"W x 45.0"H x 7.50'L with 0.33' Overlap
16 Chambers in 4 Rows
Cap Storage= 14.9 cf x 2 x 4 rows = 119.2 cf
6,957 cf Total Available Storage
Storage Group A created with Chamber Wizard
Device Routing Invert Outlet Devices
#1 Primary 0.75' 18.00" Vert. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#2 Device 1 0.75' 0.50" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#3 Device 1 2.00' 8.00" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#4 Device 1 3.00' 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
0.5' Crest Height
#5 Discarded 0.00' 0.060 in/hr Exfiltration over Surface area Phase-In= 0.01'
Discarded OutFlow Max=0.00 cfs @ 19.89 hrs HW=0.01' (Free Discharge)
L5=Exfiltration (Exfiltration Controls 0.00 cfs)
Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=0.00' (Free Discharge)
L1=Orifice/Grate ( Controls 0.00 cfs)
2=Orifice/Grate ( Controls 0.00 cfs)
3=Orifice/Grate ( Controls 0.00 cfs)
4=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)

Mars Hill University Student Center, 1-in Rainfall Detention (P Type II 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 4
Pond 1 P: StormTech Detention - Chamber Wizard Field A
Chamber Model =ADS_StormTech MC-3500 d +Cap (ADS StormTech®MC-3500 d rev 03/14 with Cap
volume)
Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf
Overall Size= 77.0"W x 45.0"H x 7.50'L with 0.33' Overlap
Cap Storage= 14.9 cf x 2 x 4 rows = 119.2 cf
77.0" Wide + 9.0" Spacing = 86.0" C-C Row Spacing
4 Chambers/Row x 7.17' Long +1.85' Cap Length x 2 = 32.38' Row Length +12.0" End Stone x 2 = 34.38'
Base Length
4 Rows x 77.0" Wide + 9.0" Spacing x 3 + 295.0" Side Stone x 2 = 77.08' Base Width
9.0" Stone Base + 45.0" Chamber Height + 12.0" Stone Cover = 5.50' Field Height
16 Chambers x 110.0 cf + 14.9 cf Cap Volume x 2 x 4 Rows = 1,878.4 cf Chamber Storage
14,575.7 cf Field - 1,878.4 cf Chambers = 12,697.3 cf Stone x 40.0%Voids = 5,078.9 cf Stone Storage
Chamber Storage + Stone Storage = 6,957.3 cf = 0.160 of
Overall Storage Efficiency = 47.7%
Overall System Size = 34.38' x 77.08' x 5.50'
16 Chambers
539.8 cy Field
470.3 cy Stone
4 f, = U t A

Mars Hill University Student Center, 1-in Rainfall Detention (P Type 11 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 5
Pond 1 P: StormTech Detention
Hydrograph
I I I I 1 I 1 1 I I I I 1 1
/r I I 1 I 1 I 1 1 II 1 I I 1 1 I I 1 I 1 ■Inflow
-r 1. 0.00cfs r-1-rr--1-r--r-r--r-r1-r11-r-I-1-r-r1-- . ❑Outflow
I 1 1 I I 1 1 1 I 1 I I I I I I AI
Ti r r I I 1 r r r r ! inflow Area-14,462 sf p Primary
I I I I 1 I I I y
0.001 . I 1 1 1 , I I , I 1 1 - I 1 1 1 _
___1___I_1 I_J L 1 1 L 1 1 1 Peak-Eiev-0.01'
0.001= I I I I I I I I 1
_-J.-L_I_1 4_ 4_I_--1-L__1-L__1_1_J_L __I-- - -- -.-. :
0.001- I I 1 1 II It 1 1 IIIIIII
---+-I--1- -- -1---+-I---+-r--t-1--;-+-r.�-1--Storage=9-rf
0.001= 1 I I I I 1 1 I 1 1 1 1 1 I 1 1
--- -r-I 1-r---,-r--r-r 1,-r-1-1-r-r 1-r-I-1-r 1-r-r 1-
0.001 I I I 0.00 Ct8 I I I I I I 1 I I I 1 I I I I I I
' I 1 1 / / 1 1 1 1 I I I 1 1 1 1 1 - r 1 1 1 1 1 1 1
0.001 O.00 cfs
_ 1 1 1 � 11 II I I 1 1 1 1 I 1 1 1 I 1 1 1 1 1 1 _
0.001 1 I 1 j IL
I I_
I I I I I I I I 1 1 1 I I I I I
-L_I_ _1_L__1_L__1_L J_L_I_J-L_I_J_L_I_1_L J_1_L_I_
0.001 I I 1 1 1 1 1 I I I I I I I I I I I I I I I 1 I
Ul _+_ti._I_ i _+ _y_r__+-I---+-I--I-+-1-a-+-1-+-4-I-1-I--I-+-I--I-.
I.) 0.000- I I %1 1 11 II I I I I I 1 1 I I 1 I I I I 1 I 1
- ---+-I--1 %,„ -1-1-- �� -1 1- -1-r--t-I-1-1--I-1-r-I-i-r-1-1-r-1-t-r-,-
3 0.000 I 1 % I I /) 1 1 II 1 1 1 I 1 I I I I I 1 1 I 1 1 I I
o 0.000- ---r-r-I j/ 1—r-- ?i�-• 1-r--r-r--1-r1-r-1-1-r-1-1-r-I-1-r-1-T-r1-
LL _ I - 1 -/,j•1 I 1 I I I I I I I I 1 , I I I I 1 I 1 I
I % 1 I --j/., I 1 1 I I I I I I I I I I I I I I I I I
0.000= _1_ I 1 2•_L IL I I I j I _f L I I I I I L 1 I I I
rf
0.000= I  I 1 I
,;j/ I I I IIIIIIIIIIIIIIIII
, _L L % J_L__J j� __1_L--1_L J_L_I_J_LI _I_J_IL_I_JI_IL_II_11 _LJI
_.
0.000- ___+_1- % -1_}__4_ -+_F__+_F-i_+_1- i-1--I-+-1--I-+-I--I-+-I--1_.0.000= 1 yi/ 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
0.000
0 /
/ _
0= „,• —, , ,„ , ....
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 5860 6264 66 68 70 72
Time (hours)
Pond 1 P: StormTech Detention
Stage-Discharge
1 1 1
I 1 I 1
I ❑Total
1 -~ ■Discarded
p Primary
1
5 �/
-
a 1
w //���Shar��/ed�angular Weir
c
3' !` _ . -
0
a, /i '' Orifice/Grate
O 2 �V,V
?j,c
1- / Orifice/Grate+Orifice/Grate
Exfiltration
0 / . . . , /
0 2 4 6 8 10 12 14 16
Discharge (cfs)

Mars Hill University Student Center, 1-in Rainfall Detention (P Type 11 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 6
Pond 1 P: StormTech Detention
Stage-Area-Storage
Surface/HorizontalRNetted Area(sq-ft)
0 500 1,000 1,500 2,000 2,500 0 Surface
l 1 . 0 Storage
5- /// /
4 , ///
// +
-- - ///
ce
/,
co
W 2_ �/� 1 :,
1 // ADS StormTech MC-3500 d+Cap 1
// — 1
1
Wield A;
o- .
0 1,000 2,000 3,000 4,000 5,000 6,000
Storage(cubic-feet)

Mars Hill University Student Center, 1-in Rainfall Detention (P Type 11 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 7
Hydrograph for Pond 1P: StormTech Detention
Time Inflow Storage Elevation Outflow Discarded Primary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 0.00 0.00 0.00 0.00
2.50 0.00 0 0.00 0.00 0.00 0.00
5.00 0.00 0 0.00 0.00 0.00 0.00
7.50 0.00 0 0.00 0.00 0.00 0.00
10.00 0.00 0 0.00 0.00 0.00 0.00
12.50 0.00 0 0.00 0.00 0.00 0.00
15.00 0.00 6 0.01 0.00 0.00 0.00
17.50 0.00 8 0.01 0.00 0.00 0.00
20.00 0.00 9 0.01 0.00 0.00 0.00
22.50 0.00 9 0.01 0.00 0.00 0.00
25.00 0.00 7 0.01 0.00 0.00 0.00
27.50 0.00 4 0.00 0.00 0.00 0.00
30.00 0.00 2 0.00 0.00 0.00 0.00
32.50 0.00 1 0.00 0.00 0.00 0.00
35.00 0.00 1 0.00 0.00 0.00 0.00
37.50 0.00 0 0.00 0.00 0.00 0.00
40.00 0.00 0 0.00 0.00 0.00 0.00
42.50 0.00 0 0.00 0.00 0.00 0.00
45.00 0.00 0 0.00 0.00 0.00 0.00
47.50 0.00 0 0.00 0.00 0.00 0.00
50.00 0.00 0 0.00 0.00 0.00 0.00
52.50 0.00 0 0.00 0.00 0.00 0.00
55.00 0.00 0 0.00 0.00 0.00 0.00
57.50 0.00 0 0.00 0.00 0.00 0.00
60.00 0.00 0 0.00 0.00 0.00 0.00
62.50 0.00 0 0.00 0.00 0.00 0.00
65.00 0.00 0 0.00 0.00 0.00 0.00
67.50 0.00 0 0.00 0.00 0.00 0.00
70.00 0.00 0 0.00 0.00 0.00 0.00

Mars Hill University Student Center, 1-in Rainfall Detention (P Type II 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 8
Stage-Discharge for Pond 1 P: StormTech Detention
Elevation Discharge Discarded Primary Elevation Discharge Discarded Primary
(feet) (cfs) (cfs) (cfs) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0.00 0.00 5.20 16.37 0.00 16.37
0.10 0.00 0.00 0.00 5.30 16.59 0.00 16.59
0.20 0.00 0.00 0.00 5.40 16.81 0.00 16.80
0.30 0.00 0.00 0.00 5.50 17.02 0.00 17.02
0.40 0.00 0.00 0.00
0.50 0.00 0.00 0.00
0.60 0.00 0.00 0.00
0.70 0.00 0.00 0.00
0.80 0.00 0.00 0.00
0.90 0.01 0.00 0.00
1.00 0.01 0.00 0.00
1.10 0.01 0.00 0.00
1.20 0.01 0.00 0.00
1.30 0.01 0.00 0.00
1.40 0.01 0.00 0.01
1.50 0.01 0.00 0.01
1.60 0.01 0.00 0.01
1.70 0.01 0.00 0.01
1.80 0.01 0.00 0.01
1.90 0.01 0.00 0.01
2.00 0.01 0.00 0.01
2.10 0.05 0.00 0.04
2.20 0.15 0.00 0.14
2.30 0.30 0.00 0.29
2.40 0.48 0.00 0.48
2.50 0.69 0.00 0.68
2.60 0.89 0.00 0.88
2.70 1.03 0.00 1.03
2.80 1.16 0.00 1.16
2.90 1.28 0.00 1.27
3.00 1.39 0.00 1.38
3.10 1.91 0.00 1.90
3.20 2.79 0.00 2.79
3.30 3.94 0.00 3.94
3.40 5.31 0.00 5.31
3.50 6.89 0.00 6.89
3.60 8.67 0.00 8.66
3.70 10.64 0.00 10.63
3.80 12.79 0.00 12.79
3.90 13.19 0.00 13.18
4.00 13.46 0.00 13.45
4.10 13.72 0.00 13.72
4.20 13.99 0.00 13.98
4.30 14.24 0.00 14.24
4.40 14.49 0.00 14.49
4.50 14.74 0.00 14.74
4.60 14.98 0.00 14.98
4.70 15.22 0.00 15.22
4.80 15.46 0.00 15.46
4.90 15.69 0.00 15.69
5.00 15.92 0.00 15.92
5.10 16.15 0.00 16.14

Mars Hill University Student Center, 1-in Rainfall Detention (P Type II 24-hr Rainfall=1.00"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 9
Stage-Area-Storage for Pond 1 P: StormTech Detention
Elevation Surface Storage Elevation Surface Storage
(feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet)
0.00 2,650 0 5.20 2,650 6,639
0.10 2,650 106 5.30 2,650 6,745
0.20 2,650 212 5.40 2,650 6,851
0.30 2,650 318 5.50 2,650 6,957
0.40 2,650 424
0.50 2,650 530
0.60 2,650 636
0.70 2,650 742
0.80 2,650 870
0.90 2,650 1,018
1.00 2,650 1,167
1.10 2,650 1,315
1.20 2,650 1,463
1.30 2,650 1,611
1.40 2,650 1,758
1.50 2,650 1,905
1.60 2,650 2,051
1.70 2,650 2,197
1.80 2,650 2,343
1.90 2,650 2,488
2.00 2,650 2,633
2.10 2,650 2,777
2.20 2,650 2,920
2.30 2,650 3,063
2.40 2,650 3,205
2.50 2,650 3,346
2.60 2,650 3,487
2.70 2,650 3,627
2.80 2,650 3,766
2.90 2,650 3,904
3.00 2,650 4,041
3.10 2,650 4,178
3.20 2,650 4,313
3.30 2,650 4,447
3.40 2,650 4,579
3.50 2,650 4,710
3.60 2,650 4,840
3.70 2,650 4,968
3.80 2,650 5,094
3.90 2,650 5,218
4.00 2,650 5,340
4.10 2,650 5,458
4.20 2,650 5,571
4.30 2,650 5,682
4.40 2,650 5,790
4.50 2,650 5,897
4.60 2,650 6,003
4.70 2,650 6,109
4.80 2,650 6,215
4.90 2,650 6,321
5.00 2,650 6,427
5.10 2,650 6,533

Mars Hill University Student Center, 1-yr Storm (Pre-Const) Type 11 24-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1 S: Runoff
Mars Hill University Student Center, 1-yr. Storm Event (Pre-Construction)
[49] Hint: Tc<2dt may require smaller dt
Runoff = 0.00 cfs @ 15.41 hrs, Volume= 0.001 af, Depth= 0.03"
Routed to nonexistent node 1 P
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-50.00 hrs, dt= 0.05 hrs
Type II 24-hr Rainfall=2.25"
Area (ac) CN Description
0.233 61 >75% Grass cover, Good, HSG B
0.099 39 >75% Grass cover, Good, HSG A
0.332 54 Weighted Average
0.332 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.7 75 0.0200 0.22 Lag/CN Method,
Subcatchment 1 S: Runoff
Hydrograph
_I-_- -_r__,__-_-- -_1__-__r__,_- . ..r__1__ --- -_1__----r I -I
0.001 I L J I 1 L 1 I I I L I- ---- - I
I I I 1 I I 1 I I 1 I I . 1 1 , ❑Runoff
0.001-1 -1-- I---t 1---1--+ r- I r 1 t--r----+ 1 , +-
10.00 f�f 1 it I I I I 1 I I I
0.001 T ell
o.00,_ i 24h
-i Yp r
4-- ----- - �_-1-
0.001 I= - - -
0.001 • 7 1 I I 1
° Rainfall-2.25"
0.001: ,--,--r--1--� 1 r r-�
' ;- 1-- --;_-1- 1- -; I-- Runoff Area=0.332 ac-
0.001_ 1--r- - r-- r r r 0.001
= 1 Runoff Volume=0.001.6f.
1 I
0.001= r r
0.001 , 1 1 Runoff Depth=0.03"
0.001= i -I
Flow Length=75'
_ � � I I I I I I I I
0.001= r -1- r r
J L Slope=0.0200 -'/'- -
0.0004 ,--r r r Tc=,5.7 m i n
1__1__L____1__ �__1__L_-I_ J L 1 -
0.000 c I � I I I I I I I �
0.000, + -r Y r r 7 r r r
0.000= CN=54
I I I I I I ; � I �
0.000i + f — — - t- —I— —I— *--1--' --+
0.0003i 1 I ,
0.000 t-
03
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Time (hours)

Mars Hill University Student Center, 1-yr Storm (Pre-Const) Type 1124-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: Runoff
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 26.00 2.25 0.03 0.00
0.50 0.01 0.00 0.00 26.50 2.25 0.03 0.00
1.00 0.02 0.00 0.00 27.00 2.25 0.03 0.00
1.50 0.04 0.00 0.00 27.50 2.25 0.03 0.00
2.00 0.05 0.00 0.00 28.00 2.25 0.03 0.00
2.50 0.06 0.00 0.00 28.50 2.25 0.03 0.00
3.00 0.08 0.00 0.00 29.00 2.25 0.03 0.00
3.50 0.09 0.00 0.00 29.50 2.25 0.03 0.00
4.00 0.11 0.00 0.00 30.00 2.25 0.03 0.00
4.50 0.12 0.00 0.00 30.50 2.25 0.03 0.00
5.00 0.14 0.00 0.00 31.00 2.25 0.03 0.00
5.50 0.16 0.00 0.00 31.50 2.25 0.03 0.00
6.00 0.18 0.00 0.00 32.00 2.25 0.03 0.00
6.50 0.20 0.00 0.00 32.50 2.25 0.03 0.00
7.00 0.22 0.00 0.00 33.00 2.25 0.03 0.00
7.50 0.25 0.00 0.00 33.50 2.25 0.03 0.00
8.00 0.27 0.00 0.00 34.00 2.25 0.03 0.00
8.50 0.30 0.00 0.00 34.50 2.25 0.03 0.00
9.00 0.33 0.00 0.00 35.00 2.25 0.03 0.00
9.50 0.37 0.00 0.00 35.50 2.25 0.03 0.00
10.00 0.41 0.00 0.00 36.00 2.25 0.03 0.00
10.50 0.46 0.00 0.00 36.50 2.25 0.03 0.00
11.00 0.53 0.00 0.00 37.00 2.25 0.03 0.00
11.50 0.64 0.00 0.00 37.50 2.25 0.03 0.00
12.00 1.49 0.00 0.00 38.00 2.25 0.03 0.00
12.50 1.65 0.00 0.00 38.50 2.25 0.03 0.00
13.00 1.74 0.00 0.00 39.00 2.25 0.03 0.00
13.50 1.80 0.00 0.00 39.50 2.25 0.03 0.00
14.00 1.84 0.00 0.00 40.00 2.25 0.03 0.00
14.50 1.88 0.00 0.00 40.50 2.25 0.03 0.00
15.00 1.92 0.01 0.00 41.00 2.25 0.03 0.00
15.50 1.95 0.01 0.00 41.50 2.25 0.03 0.00
16.00 1.98 0.01 0.00 42.00 2.25 0.03 0.00
16.50 2.01 0.01 0.00 42.50 2.25 0.03 0.00
17.00 2.03 0.01 0.00 43.00 2.25 0.03 0.00
17.50 2.05 0.01 0.00 43.50 2.25 0.03 0.00
18.00 2.07 0.02 0.00 44.00 2.25 0.03 0.00
18.50 2.09 0.02 0.00 44.50 2.25 0.03 0.00
19.00 2.11 0.02 0.00 45.00 2.25 0.03 0.00
19.50 2.13 0.02 0.00 45.50 2.25 0.03 0.00
20.00 2.14 0.02 0.00 46.00 2.25 0.03 0.00
20.50 2.16 0.02 0.00 46.50 2.25 0.03 0.00
21.00 2.17 0.02 0.00 47.00 2.25 0.03 0.00
21.50 2.18 0.03 0.00 47.50 2.25 0.03 0.00
22.00 2.20 0.03 0.00 48.00 2.25 0.03 0.00
22.50 2.21 0.03 0.00 48.50 2.25 0.03 0.00
23.00 2.22 0.03 0.00 49.00 2.25 0.03 0.00
23.50 2.24 0.03 0.00 49.50 2.25 0.03 0.00
24.00 2.25 0.03 0.00 50.00 2.25 0.03 0.00
24.50 2.25 0.03 0.00
25.00 2.25 0.03 0.00
25.50 2.25 0.03 0.00

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type II 24-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1S: Runoff
Mars Hill University Student Center, 1-yr Storm Event (Post-Construction)
[49] Hint: Tc<2dt may require smaller dt
Runoff = 0.28 cfs @ 11.95 hrs, Volume= 570 cf, Depth= 0.47"
Routed to Pond 1 P : StormTech Detention
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-50.00 hrs, dt= 0.05 hrs
Type II 24-hr Rainfall=2.25"
Area (ac) CN Description
* 0.166 98 Pavements, Sidewalks, Roofs
0.083 61 >75% Grass cover, Good, HSG B
0.083 39 >75% Grass cover, Good, HSG A
0.332 74 Weighted Average
0.166 50.00% Pervious Area
0.166 50.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
3.4 75 0.0200 0.37 LagICN Method,
Subcatchment 1 S: Runoff
Hydrograph
/ ❑Runoff`
0.3: 1 1 10.28 cfs]-
T--
;
0.28 ' Type II 24-hr
0.26 I Rainfall=2.25"
Q 24-
Runoff Area=0.332 ac
1 .0.2z: - — — _
0.2 1
Runoff Volume=570 cf
w °'$- Runoff Depth=0.47"
3 0.16-
6: 0.14 Flow Length=75'
0.12- ' E - - _ Slope=0.0200 '/'..
0.08- • Tc=3.4 min
0.06 1,:, CN=74
o.oa c 0
0.02- i ,, /
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Time (hours)

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type II 24-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: Runoff
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 26.00 2.25 0.47 0.00
0.50 0.01 0.00 0.00 26.50 2.25 0.47 0.00
1.00 0.02 0.00 0.00 27.00 2.25 0.47 0.00
1.50 0.04 0.00 0.00 27.50 2.25 0.47 0.00
2.00 0.05 0.00 0.00 28.00 2.25 0.47 0.00
2.50 0.06 0.00 0.00 28.50 2.25 0.47 0.00
3.00 0.08 0.00 0.00 29.00 2.25 0.47 0.00
3.50 0.09 0.00 0.00 29.50 2.25 0.47 0.00
4.00 0.11 0.00 0.00 30.00 2.25 0.47 0.00
4.50 0.12 0.00 0.00 30.50 2.25 0.47 0.00
5.00 0.14 0.00 0.00 31.00 2.25 0.47 0.00
5.50 0.16 0.00 0.00 31.50 2.25 0.47 0.00
6.00 0.18 0.00 0.00 32.00 2.25 0.47 0.00
6.50 0.20 0.00 0.00 32.50 2.25 0.47 0.00
7.00 0.22 0.00 0.00 33.00 2.25 0.47 0.00
7.50 0.25 0.00 0.00 33.50 2.25 0.47 0.00
8.00 0.27 0.00 0.00 34.00 2.25 0.47 0.00
8.50 0.30 0.00 0.00 34.50 2.25 0.47 0.00
9.00 0.33 0.00 0.00 35.00 2.25 0.47 0.00
9.50 0.37 0.00 0.00 35.50 2.25 0.47 0.00
10.00 0.41 0.00 0.00 36.00 2.25 0.47 0.00
10.50 0.46 0.00 0.00 36.50 2.25 0.47 0.00
11.00 0.53 0.00 0.00 37.00 2.25 0.47 0.00
11.50 0.64 0.00 0.00 37.50 2.25 0.47 0.00
12.00 1.49 0.14 0.22 38.00 2.25 0.47 0.00
12.50 1.65 0.20 0.03 38.50 2.25 0.47 0.00
13.00 1.74 0.24 0.02 39.00 2.25 0.47 0.00
13.50 1.80 0.26 0.02 39.50 2.25 0.47 0.00
14.00 1.84 0.28 0.01 40.00 2.25 0.47 0.00
14.50 1.88 0.30 0.01 40.50 2.25 0.47 0.00
15.00 1.92 0.31 0.01 41.00 2.25 0.47 0.00
15.50 1.95 0.33 0.01 41.50 2.25 0.47 0.00
16.00 1.98 0.34 0.01 42.00 2.25 0.47 0.00
16.50 2.01 0.35 0.01 42.50 2.25 0.47 0.00
17.00 2.03 0.36 0.01 43.00 2.25 0.47 0.00
17.50 2.05 0.37 0.01 43.50 2.25 0.47 0.00
18.00 2.07 0.38 0.01 44.00 2.25 0.47 0.00
18.50 2.09 0.39 0.01 44.50 2.25 0.47 0.00
19.00 2.11 0.40 0.01 45.00 2.25 0.47 0.00
19.50 2.13 0.41 0.01 45.50 2.25 0.47 0.00
20.00 2.14 0.42 0.00 46.00 2.25 0.47 0.00
20.50 2.16 0.43 0.00 46.50 2.25 0.47 0.00
21.00 2.17 0.43 0.00 47.00 2.25 0.47 0.00
21.50 2.18 0.44 0.00 47.50 2.25 0.47 0.00
22.00 2.20 0.45 0.00 48.00 2.25 0.47 0.00
22.50 2.21 0.45 0.00 48.50 2.25 0.47 0.00
23.00 2.22 0.46 0.00 49.00 2.25 0.47 0.00
23.50 2.24 0.47 0.00 49.50 2.25 0.47 0.00
24.00 2.25 0.47 0.00 50.00 2.25 0.47 0.00
24.50 2.25 0.47 0.00
25.00 2.25 0.47 0.00
25.50 2.25 0.47 0.00

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type II 24-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 3
Summary for Pond 1 P: StormTech Detention
Detention Facility
Inflow Area = 14,462 sf, 50.00% Impervious, Inflow Depth = 0.47"
Inflow = 0.28 cfs @ 11.95 hrs, Volume= 570 cf
Outflow = 0.00 cfs @ 24.00 hrs, Volume= 324 cf, Atten= 99%, Lag= 722.7 min
Discarded = 0.00 cfs @ 11.85 hrs, Volume= 197 cf
Primary = 0.00 cfs @ 24.00 hrs, Volume= 127 cf
Routed to nonexistent node 1 R
Routing by Stor-Ind method, Time Span= 0.00-50.00 hrs, dt= 0.05 hrs
Peak Elev= 0.90' @ 24.00 hrs Surf.Area= 1,029 sf Storage= 436 cf
Plug-Flow detention time= 941.5 min calculated for 323 cf (57% of inflow)
Center-of-Mass det. time= 797.0 min ( 1,680.2 - 883.2 )
Volume Invert Avail.Storage Storage Description
#1A 0.00' 1,511 cf 29.92'W x 34.38'L x 5.50'H Field A
5,657 cf Overall - 1,878 cf Embedded = 3,779 cf x 40.0%Voids
#2A 0.75' 1,878 cf ADS_StormTech MC-3500 d +Cap x 16 Inside#1
Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf
Overall Size= 77.0"W x 45.0"H x 7.50'L with 0.33' Overlap
16 Chambers in 4 Rows
Cap Storage= 14.9 cf x 2 x 4 rows = 119.2 cf
3,390 cf Total Available Storage
Storage Group A created with Chamber Wizard
Device Routing Invert Outlet Devices
#1 Primary 0.75' 18.00" Vert. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#2 Device 1 0.75' 0.50"Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#3 Device 1 2.00' 8.00" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#4 Device 1 3.00' 3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
0.5' Crest Height
#5 Discarded 0.00' 0.060 in/hr Exfiltration over Surface area Phase-In= 0.01'
Discarded OutFlow Max=0.00 cfs @ 11.85 hrs HW=0.06' (Free Discharge)
L5=Exfiltration (Exfiltration Controls 0.00 cfs)
Primary OutFlow Max=0.00 cfs @ 24.00 hrs HW=0.90' (Free Discharge)
4-1=Orifice/Grate (Passes 0.00 cfs of 0.12 cfs potential flow)
4-2=Orifice/Grate (Orifice Controls 0.00 cfs @ 1.74 fps)
-3=OrificelGrate ( Controls 0.00 cfs)
-4=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type II 24-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 4
Pond 1 P: StormTech Detention - Chamber Wizard Field A
Chamber Model =ADS_StormTech MC-3500 d +Cap(ADS StormTech® MC-3500 d rev 03/14 with Cap
volume)
Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf
Overall Size= 77.0"W x 45.0"H x 7.50'L with 0.33' Overlap
Cap Storage= 14.9 cf x 2 x 4 rows = 119.2 cf
77.0" Wide+ 9.0" Spacing = 86.0" C-C Row Spacing
4 Chambers/Row x 7.17' Long +1.85' Cap Length x 2 = 32.38' Row Length +12.0" End Stone x 2 = 34.38'
Base Length
4 Rows x 77.0" Wide + 9.0" Spacing x 3 + 12.0" Side Stone x 2 = 29.92' Base Width
9.0" Stone Base + 45.0" Chamber Height + 12.0" Stone Cover = 5.50' Field Height
16 Chambers x 110.0 cf + 14.9 cf Cap Volume x 2 x 4 Rows = 1,878.4 cf Chamber Storage
5,656.9 cf Field - 1,878.4 cf Chambers = 3,778.5 cf Stone x 40.0% Voids = 1,511.4 cf Stone Storage
Chamber Storage + Stone Storage = 3,389.8 cf = 0.078 of
Overall Storage Efficiency = 59.9%
Overall System Size = 34.38' x 29.92' x 5.50'
16 Chambers
209.5 cy Field
139.9 cy Stone
NVOW

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type II 24-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 5
Pond 1 P: StormTech Detention
Hydrograph
, I
, r 7 T I 7 1 D Inflow
' I 0.28ds i __ e L1 Outflow
--- ---- - -- •Inflow Area=14,462 sf Discarded
fI 0Prmary'
0.3= -;———- ----- 1---I- -+
Peak Elev=0.90'
0.26= I I Storage=436 cf
0.24_ I I --— ----
0.22= T -r , r l I
, , I
0.2' -r r T r 1— —t—-1 r-7— —T--II r-7 r
,
w 0.18 --+----r--- + y
I
•
: 0.14_ _1_ _L_ __1L_J____1____L_J____1_J__L_1____1____
I
0.12 I ' ,
I ,
I , I I
O.OSi r T r r r i Ti r Ti
i I
0.06
0.04_ '
0.00 as
0.00 ds --
0.02i ' 0.00 cfs
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Time (hours)
Pond 1 P: StormTech Detention
Stage-Discharge
,
❑Total
4 "- - - -- U Discarded
®Primary
5 /
w r "...or',
Sharp-Crested Rectangular Weir
c 3 /!
o
ro
to j " Orifice/Grate •
2 /j
/l
ij ,
1 �� Orifice/Grate+Orifice/Grate
i
Exfiltration /
0 2 4 6 8 10 12 14 16
Discharge (cfs)

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type 1124-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 6
Pond 1 P: StormTech Detention
Stage-Area-Storage
Surface/Horizontal/Wetted Area(sy•ft)
0 100 200 300 400 500 600 700 800 900 1,000 ❑Surface`
Storage
Si
0%
+ 9
4 /// 0
��
o
i
0
1 i/r ADS_StormTech MC-3500 d+Cap
i
Field A -
0 500 1,000 1,500 2,000 2,500 3,000
Storage(cubic-feet)

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type II 24-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 7
Hydrograph for Pond 1 P: StormTech Detention
Time Inflow Storage Elevation Outflow Discarded Primary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 0.00 0.00 0.00 0.00
1.00 0.00 0 0.00 0.00 0.00 0.00
2.00 0.00 0 0.00 0.00 0.00 0.00
3.00 0.00 0 0.00 0.00 0.00 0.00
4.00 0.00 0 0.00 0.00 0.00 0.00
5.00 0.00 0 0.00 0.00 0.00 0.00
6.00 0.00 0 0.00 0.00 0.00 0.00
7.00 0.00 0 0.00 0.00 0.00 0.00
8.00 0.00 0 0.00 0.00 0.00 0.00
9.00 0.00 0 0.00 0.00 0.00 0.00
10.00 0.00 0 0.00 0.00 0.00 0.00
11.00 0.00 0 0.00 0.00 0.00 0.00
12.00 0.22 140 0.34 0.00 0.00 0.00
13.00 0.02 274 0.67 0.00 0.00 0.00
14.00 0.01 324 0.77 0.00 0.00 0.00
15.00 0.01 356 0.81 0.00 0.00 0.00
16.00 0.01 379 0.83 0.00 0.00 0.00
17.00 0.01 396 0.85 0.00 0.00 0.00
18.00 0.01 408 0.87 0.00 0.00 0.00
19.00 0.01 418 0.88 0.00 0.00 0.00
20.00 0.00 424 0.89 0.00 0.00 0.00
21.00 0.00 428 0.89 0.00 0.00 0.00
22.00 0.00 431 0.90 0.00 0.00 0.00
23.00 0.00 434 0.90 0.00 0.00 0.00
24.00 0.00 436 0.90 0.00 0.00 0.00
25.00 0.00 424 0.89 0.00 0.00 0.00
26.00 0.00 411 0.87 0.00 0.00 0.00
27.00 0.00 398 0.86 0.00 0.00 0.00
28.00 0.00 387 0.84 0.00 0.00 0.00
29.00 0.00 376 0.83 0.00 0.00 0.00
30.00 0.00 365 0.82 0.00 0.00 0.00
31.00 0.00 356 0.81 0.00 0.00 0.00
32.00 0.00 347 0.80 0.00 0.00 0.00
33.00 0.00 339 0.79 0.00 0.00 0.00
34.00 0.00 332 0.78 0.00 0.00 0.00
35.00 0.00 325 0.77 0.00 0.00 0.00
36.00 0.00 319 0.76 0.00 0.00 0.00
37.00 0.00 313 0.76 0.00 0.00 0.00
38.00 0.00 308 0.75 0.00 0.00 0.00
39.00 0.00 303 0.74 0.00 0.00 0.00
40.00 0.00 298 0.72 0.00 0.00 0.00
41.00 0.00 293 0.71 0.00 0.00 0.00
42.00 0.00 288 0.70 0.00 0.00 0.00
43.00 0.00 282 0.69 0.00 0.00 0.00
44.00 0.00 277 0.67 0.00 0.00 0.00
45.00 0.00 272 0.66 0.00 0.00 0.00
46.00 0.00 267 0.65 0.00 0.00 0.00
47.00 0.00 262 0.64 0.00 0.00 0.00
48.00 0.00 257 0.62 0.00 0.00 0.00
49.00 0.00 252 0.61 0.00 0.00 0.00
50.00 0.00 246 0.60 0.00 0.00 0.00

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type 1124-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 8
Stage-Discharge for Pond 1 P: StormTech Detention
Elevation Discharge Discarded Primary Elevation Discharge Discarded Primary
(feet) (cfs) (cfs) (cfs) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0.00 0.00 5.20 16.37 0.00 16.37
0.10 0.00 0.00 0.00 5.30 16.59 0.00 16.59
0.20 0.00 0.00 0.00 5.40 16.80 0.00 16.80
0.30 0.00 0.00 0.00 5.50 17.02 0.00 17.02
0.40 0.00 0.00 0.00
0.50 0.00 0.00 0.00
0.60 0.00 0.00 0.00
0.70 0.00 0.00 0.00
0.80 0.00 0.00 0.00
0.90 0.00 0.00 0.00
1.00 0.00 0.00 0.00
1.10 0.01 0.00 0.00
1.20 0.01 0.00 0.00
1.30 0.01 0.00 0.00
1.40 0.01 0.00 0.01
1.50 0.01 0.00 0.01
1.60 0.01 0.00 0.01
1.70 0.01 0.00 0.01
1.80 0.01 0.00 0.01
1.90 0.01 0.00 0.01
2.00 0.01 0.00 0.01
2.10 0.04 0.00 0.04
2.20 0.14 0.00 0.14
2.30 0.29 0.00 0.29
2.40 0.48 0.00 0.48
2.50 0.69 0.00 0.68
2.60 0.88 0.00 0.88
2.70 1.03 0.00 1.03
2.80 1.16 0.00 1.16
2.90 1.28 0.00 1.27
3.00 1.38 0.00 1.38
3.10 1.80 0.00 1.80
3.20 2.48 0.00 2.48
3.30 3.36 0.00 3.36
3.40 4.40 0.00 4.40
3.50 5.59 0.00 5.59
3.60 6.92 0.00 6.92
3.70 8.39 0.00 8.39
3.80 9.99 0.00 9.99
3.90 11.72 0.00 11.72
4.00 13.45 0.00 13.45
4.10 13.72 0.00 13.72
4.20 13.98 0.00 13.98
4.30 14.24 0.00 14.24
4.40 14.49 0.00 14.49
4.50 14.74 0.00 14.74
4.60 14.98 0.00 14.98
4.70 15.22 0.00 15.22
4.80 15.46 0.00 15.46
4.90 15.69 0.00 15.69
5.00 15.92 0.00 15.92
5.10 16.15 0.00 16.14

Mars Hill University Student Center, 1-yr Storm Detention (Pos Type II 24-hr Rainfall=2.25"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 9
Stage-Area-Storage for Pond 1 P: StormTech Detention
Elevation Surface Storage Elevation Surface Storage
(feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet)
0.00 1,029 0 5.20 1,029 3,266
0.10 1,029 41 5.30 1,029 3,308
0.20 1,029 82 5.40 1,029 3,349
0.30 1,029 123 5.50 1,029 3,390
0.40 1,029 165
0.50 1,029 206
0.60 1,029 247
0.70 1,029 288
0.80 1,029 351
0.90 1,029 435
1.00 1,029 518
1.10 1,029 602
1.20 1,029 685
1.30 1,029 768
1.40 1,029 850
1.50 1,029 932
1.60 1,029 1,014
1.70 1,029 1,095
1.80 1,029 1,175
1.90 1,029 1,256
2.00 1,029 1,335
2.10 1,029 1,415
2.20 1,029 1,493
2.30 1,029 1,571
2.40 1,029 1,648
2.50 1,029 1,725
2.60 1,029 1,801
2.70 1,029 1,876
2.80 1,029 1,950
2.90 1,029 2,023
3.00 1,029 2,096
3.10 1,029 2,167
3.20 1,029 2,237
3.30 1,029 2,306
3.40 1,029 2,374
3.50 1,029 2,440
3.60 1,029 2,505
3.70 1,029 2,568
3.80 1,029 2,629
3.90 1,029 2,689
4.00 1,029 2,745
4.10 1,029 2,798
4.20 1,029 2,847
4.30 1,029 2,893
4.40 1,029 2,936
4.50 1,029 2,978
4.60 1,029 3,020
4.70 1,029 3,061
4.80 1,029 3,102
4.90 1,029 3,143
5.00 1,029 3,184
5.10 1,029 3,225

Mars Hill University Student Center, 10-yr Storm (Pre-Const) Type II 24-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 1020-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1S: Runoff
Mars Hill University Student Center, 10-yr. Storm Event (Pre-Construction)
[49] Hint: Tc<2dt may require smaller dt
Runoff = 0.20 cfs @ 12.00 hrs, Volume= 0.013 af, Depth= 0.47"
Routed to nonexistent node 1P
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs
Type II 24-hr Rainfall=3.96"
Area (ac) CN Description
0.233 61 >75% Grass cover, Good, HSG B
0.099 39 >75% Grass cover, Good, HSG A
0.332 54 Weighted Average
0.332 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.7 75 0.0200 0.22 Lag/CN Method,
Subcatchment 1S: Runoff
Hydrograph
/' - I I I _ - I I I I I I
/ I - --r - I I r 7 r 1 r I r r
0 22-I ,---'--J--'- -I--- I 1 1 I I 1 I I L 1 1 1 I 1 1 1 .Runoff
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
0.211'' 1 J I 10.20 C/S I I 1 L 1 J L 1 1 1 LI I J L I 1 L
1 1 7 ;--r -;- --r r--�- -T e 1124-h1
0.2:- .--1--�--. ----,-- -Type r
- I 1 I I I I 1 1 1
0.19 • I 1 1 r I , + I I 1 1 -
0.184" 1 1 L 1 1 - 1 L ' ' ' I
I I I I i I I I � IL Rainfall=3.96"- -
0.17� --'-- '---a---, i -1--.1-- --1---- - - .
I 1 Runoff Area=O.332 ac
0.1 - /
0.14 1 1__ __L__1__1__1 1 L 0.013 af
I I I 1 1 I I 1 I Runoff Volume=
w 1 1 1 1 Depth-0.47"
0.,2= - 1 , r 1 , r I , r I Runoff De t
0.11 .- 1 I 1 1 _ .- _ 1 1 1 I 1 1 1
' Flow Length=75'
o _I-_.� L ! 1 4 I ! 1
u. 0.1= -
0.06- /--I- -t r 1 -I I 1 1 1 1 I I I I 1
r 1 1 r ' Slope=0.0200 '/'- -
I I I I I I I
I 1 1 1 1 1 1 1 1 1 1 1 1
0 07-' --I-_J__L__I__J__- 1 L I J L 1 + 1 1 1
I t I I 1 I I I 1 I 1 + I 1 I Tc=5.7 min
1 I 1 1 1 1 1 1 1 1 1 1
0.054 1 r I -1- 1 r 1 -I r 1 , r
0.04-. 1 1 1 1 1 _ 4I I 1 1 I /+LN=��-
l
0.03= l-__I--J-_L__I-_J__1 1 J L 1 1 L I J L 1 I 1 L
I 1
0.o, r� '
5 6 7 8, 0.. 10..11 12
13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Time (hours)

Mars Hill University Student Center, 10-yr Storm (Pre-Const) Type 1124-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment IS: Runoff
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
5.00 0.25 0.00 0.00 18.00 3.65 0.36 0.01
5.25 0.27 0.00 0.00 18.25 3.66 0.37 0.01
5.50 0.28 0.00 0.00 18.50 3.68 0.37 0.01
5.75 0.30 0.00 0.00 18.75 3.70 0.38 0.01
6.00 0.32 0.00 0.00 19.00 3.71 0.38 0.01
6.25 0.33 0.00 0.00 19.25 3.73 0.39 0.01
6.50 0.35 0.00 0.00 19.50 3.74 0.39 0.01
6.75 0.37 0.00 0.00 19.75 3.76 0.40 0.01
7.00 0.39 0.00 0.00 20.00 3.77 0.40 0.01
7.25 0.41 0.00 0.00 20.25 3.78 0.41 0.01
7.50 0.43 0.00 0.00 20.50 3.80 0.41 0.01
7.75 0.45 0.00 0.00 20.75 3.81 0.42 0.01
8.00 0.48 0.00 0.00 21.00 3.82 0.42 0.01
8.25 0.50 0.00 0.00 21.25 3.83 0.43 0.01
8.50 0.52 0.00 0.00 21.50 3.84 0.43 0.01
8.75 0.55 0.00 0.00 21.75 3.86 0.43 0.01
9.00 0.58 0.00 0.00 22.00 3.87 0.44 0.01
9.25 0.61 0.00 0.00 22.25 3.88 0.44 0.01
9.50 0.65 0.00 0.00 22.50 3.89 0.45 0.01
9.75 0.68 0.00 0.00 22.75 3.90 0.45 0.01
10.00 0.72 0.00 0.00 23.00 3.92 0.46 0.01
10.25 0.76 0.00 0.00 23.25 3.93 0.46 0.01
10.50 0.81 0.00 0.00 23.50 3.94 0.46 0.01
10.75 0.86 0.00 0.00 23.75 3.95 0.47 0.01
11.00 0.93 0.00 0.00 24.00 3.96 0.47 0.01
11.25 1.01 0.00 0.00 24.25 3.96 0.47 0.00
11.50 1.12 0.00 0.00 24.50 3.96 0.47 0.00
11.75 1.53 0.00 0.00 24.75 3.96 0.47 0.00
12.00 2.63 0.09 0.20 25.00 3.96 0.47 0.00
12.25 2.80 0.12 0.05 25.25 3.96 0.47 0.00
12.50 2.91 0.15 0.03 25.50 3.96 0.47 0.00
12.75 2.99 0.17 0.03 25.75 3.96 0.47 0.00
13.00 3.06 0.19 0.02 26.00 3.96 0.47 0.00
13.25 3.11 0.20 0.02 26.25 3.96 0.47 0.00
13.50 3.16 0.21 0.02 26.50 3.96 0.47 0.00
13.75 3.21 0.23 0.02 26.75 3.96 0.47 0.00
14.00 3.25 0.24 0.01 27.00 3.96 0.47 0.00
14.25 3.28 0.25 0.01 27.25 3.96 0.47 0.00
14.50 3.32 0.26 0.01 27.50 3.96 0.47 0.00
14.75 3.35 0.27 0.01 27.75 3.96 0.47 0.00
15.00 3.38 0.28 0.01 28.00 3.96 0.47 0.00
15.25 3.41 0.28 0.01 28.25 3.96 0.47 0.00
15.50 3.44 0.29 0.01 28.50 3.96 0.47 0.00
15.75 3.46 0.30 0.01 28.75 3.96 0.47 0.00
16.00 3.48 0.31 0.01 29.00 3.96 0.47 0.00
16.25 3.51 0.32 0.01 29.25 3.96 0.47 0.00
16.50 3.53 0.32 0.01 29.50 3.96 0.47 0.00
16.75 3.55 0.33 0.01 29.75 3.96 0.47 0.00
17.00 3.57 0.34 0.01 30.00 3.96 0.47 0.00
17.25 3.59 0.34 0.01
17.50 3.61 0.35 0.01
17.75 3.63 0.35 0.01

Mars Hill University Student Center, 10-yr Storm Detention (Po Type II 24-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1S: Runoff
Mars Hill University Student Center., 10-yr Storm Event (Post-Construction)
[49] Hint: Tc<2dt may require smaller dt
Runoff = 1.00 cfs @ 11.94 hrs, Volume= 1,889 cf, Depth= 1.57"
Routed to Pond 1 P : StormTech Detention
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs
Type II 24-hr Rainfall=3.96"
Area (ac) CN Description
* 0.166 98 Pavements, Sidewalks, Roofs
0.083 61 >75% Grass cover, Good, HSG B
0.083 39 >75% Grass cover, Good, HSG A
0.332 74 Weighted Average
0.166 50.00% Pervious Area
0.166 50.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
3.4 75 0.0200 0.37 Lag/CN Method,
Subcatchment 1 S: Runoff
Hydrograph
/ ❑Runoff`
Type II 24-hr
•
Rainfall=3.96"
Runoff Area=0.332 ac
Runoff Volume=1 ,889 cf
Runoff Depth=1 .57"
LL -
Flow Length=75'
Slope=0.0200 'I'
E>' Tc=3.4 min
CN=74
0-
0 , 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Time (hours)

Mars Hill University Student Center, 10-yr Storm Detention (Po Type II 24-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: Runoff
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 26.00 3.96 1.57 0.00
0.50 0.02 0.00 0.00 26.50 3.96 1.57 0.00
1.00 0.04 0.00 0.00 27.00 3.96 1.57 0.00
1.50 0.06 0.00 0.00 27.50 3.96 1.57 0.00
2.00 0.09 0.00 0.00 28.00 3.96 1.57 0.00
2.50 0.11 0.00 0.00 28.50 3.96 1.57 0.00
3.00 0.14 0.00 0.00 29.00 3.96 1.57 0.00
3.50 0.16 0.00 0.00 29.50 3.96 1.57 0.00
4.00 0.19 0.00 0.00 30.00 3.96 1.57 0.00
4.50 0.22 0.00 0.00
5.00 0.25 0.00 0.00
5.50 0.28 0.00 0.00
6.00 0.32 0.00 0.00
6.50 0.35 0.00 0.00
7.00 0.39 0.00 0.00
7.50 0.43 0.00 0.00
8.00 0.48 0.00 0.00
8.50 0.52 0.00 0.00
9.00 0.58 0.00 0.00
9.50 0.65 0.00 0.00
10.00 0.72 0.00 0.00
10.50 0.81 0.00 0.00
11.00 0.93 0.01 0.01
11.50 1.12 0.04 0.03
12.00 2.63 0.68 0.70
12.50 2.91 0.85 0.08
13.00 3.06 0.94 0.05
13.50 3.16 1.01 0.04
14.00 3.25 1.07 0.03
14.50 3.32 1.12 0.03
15.00 3.38 1.16 0.03
15.50 3.44 1.20 0.02
16.00 3.48 1.23 0.02
16.50 3.53 1.26 0.02
17.00 3.57 1.29 0.02
17.50 3.61 1.32 0.02
18.00 3.65 1.34 0.02
18.50 3.68 1.37 0.02
19.00 3.71 1.39 0.01
19.50 3.74 1.41 0.01
20.00 3.77 1.43 0.01
20.50 3.80 1.45 0.01
21.00 3.82 1.47 0.01
21.50 3.84 1.48 0.01
22.00 3.87 1.50 0.01
22.50 3.89 1.52 0.01
23.00 3.92 1.53 0.01
23.50 3.94 1.55 0.01
24.00 3.96 1.57 0.01
24.50 3.96 1.57 0.00
25.00 3.96 1.57 0.00
25.50 3.96 1.57 0.00

Mars Hill University Student Center, 10-yr Storm Detention (Po Type II 24-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 3
Summary for Pond 1 P: StormTech Detention
Detention Facility
Inflow Area = 14,462 sf, 50.00% Impervious, Inflow Depth = 1.57"
Inflow = 1.00 cfs @ 11.94 hrs, Volume= 1,889 cf
Outflow = 0.02 cfs @ 17.42 hrs, Volume= 720 cf, Atten= 98%, Lag= 328.3 min
Discarded = 0.00 cfs @ 11.25 hrs, Volume= 99 cf
Primary = 0.02 cfs @ 17.42 hrs, Volume= 621 cf
Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs
Peak Elev= 2.05' @ 17.42 hrs Surf.Area= 1,029 sf Storage= 1,372 cf
Plug-Flow detention time= 524.8 min calculated for 720 cf(38% of inflow)
Center-of-Mass det. time= 390.1 min ( 1,233.9 - 843.8 )
Volume Invert Avail.Storage Storage Description
#1A 0.00' 1,511 cf 29.92'W x 34.38'L x 5.50'H Field A
5,657 cf Overall - 1,878 cf Embedded = 3,779 cf x 40.0% Voids
#2A 0.75' 1,878 cf ADS StormTech MC-3500 d +Cap x 16 Inside#1
Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf
Overall Size= 77.0"W x 45.0"H x 7.50'L with 0.33' Overlap
16 Chambers in 4 Rows
Cap Storage= 14.9 cf x 2 x 4 rows = 119.2 cf
3,390 cf Total Available Storage
Storage Group A created with Chamber Wizard
Device Routing Invert Outlet Devices
#1 Primary 0.75' 18.0"Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#2 Device 1 0.75' 0.5" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#3 Device 1 2.00' 8.0"Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#4 Device 1 3.00' 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
0.5' Crest Height
#5 Discarded 0.00' 0.060 in/hr Exfiltration over Surface area Phase-In= 0.01'
Discarded OutFlow Max=0.00 cfs @ 11.25 hrs HW=0.06' (Free Discharge)
t-5=Exfiltration (Exfiltration Controls 0.00 cfs)
Primary OutFlow Max=0.02 cfs @ 17.42 hrs HW=2.05' (Free Discharge)
t-1=Orifice/Grate (Passes 0.02 cfs of 6.29 cfs potential flow)
-2=Orifice/Grate (Orifice Controls 0.01 cfs @ 5.44 fps)
-3=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.73 fps)
-4=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)

Mars Hill University Student Center, 10-yr Storm Detention (Po Type II 24-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 4
Pond 1 P: StormTech Detention - Chamber Wizard Field A
Chamber Model =ADS_StormTech MC-3500 d +Cap(ADS StormTech® MC-3500 d rev 03/14 with Cap
volume)
Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf
Overall Size= 77.0"W x 45.0'H x 7.50'L with 0.33' Overlap
Cap Storage= 14.9 cf x 2 x 4 rows = 119.2 cf
77.0" Wide + 9.0" Spacing = 86.0" C-C Row Spacing
4 Chambers/Row x 7.17' Long +1.85' Cap Length x 2 = 32.38' Row Length +12.0" End Stone x 2 = 34.38'
Base Length
4 Rows x 77.0" Wide + 9.0" Spacing x 3 + 12.0" Side Stone x 2 = 29.92' Base Width
9.0" Stone Base +45.0" Chamber Height + 12.0" Stone Cover = 5.50' Field Height
16 Chambers x 110.0 cf + 14.9 cf Cap Volume x 2 x 4 Rows = 1,878.4 cf Chamber Storage
5,656.9 cf Field - 1,878.4 cf Chambers = 3,778.5 cf Stone x 40.0% Voids = 1,511.4 cf Stone Storage
Chamber Storage + Stone Storage = 3,389.8 cf = 0.078 of
Overall Storage Efficiency = 59.9%
Overall System Size = 34.38' x 29.92' x 5.50'
16 Chambers
209.5 cy Field
139.9 cy Stone
.moo k
IMMYF MOW MOW
nnnn

Mars Hill University Student Center, 10-yr Storm Detention (Po Type 1124-hr Rarnfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 5
• Pond 1 P: StormTech Detention
Hydrograph
/ .
I 1 1
I
■Inflow
100 rfs I ❑Outflow
InflowII Discar '
l Area=14,462 sf ❑Primarded
y
i
1 Peak Elev=2.051
Storage=1 ,372 cf
)
V -
3
O
LT.
•
0.02 cfs /,
----_./
'0.00 cfs
I'®
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Time (hours)
Pond 1 P: StormTech Detention
Stage-Discharge
I I I
I D Total
~I INDiscarded
®Primary
5 - -
4
fi� (Sharp-Crested Rectangular Weir
c 3 // /.
o ,
m
v i Orifice/Grate
W 2 j :
1 —4,4 Orifice/Grate+Orifice/Grate
f/
i
Exflltration0
0 2 4 6 8 10 12 14 16
Discharge (cfs)

Mars Hill University Student Center, 10-yr Storm Detention (Po Type 1124-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 6
Pond 1 P: StormTech Detention
Stage-Area-Storage
Surface/Horizontal/Wetted Area(sq-ft)
0 100 200 300 400 500 600 700 800 900 1,000 ❑Surface
/ ,
❑Storage ra e
5 fo
4
,
3- // '
� //�/z
III2- ,/
1- ' i -( AAS_Stom Tech MC-35bb 'f 110 1 0
[Meld Aj -- -- —
0 500 1,000 1,500 2,000 2,500 3,000
Storage(cubic-feet)

Mars Hill University Student Center, 10-yr Storm Detention (Po Type 1124-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 7
Hydrograph for Pond 1 P: StormTech Detention
Time Inflow Storage Elevation Outflow Discarded Primary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 0.00 0.00 0.00 0.00
1.00 0.00 0 0.00 0.00 0.00 0.00
2.00 0.00 0 0.00 0.00 0.00 0.00
3.00 0.00 0 0.00 0.00 0.00 0.00
4.00 0.00 0 0.00 0.00 0.00 0.00
5.00 0.00 0 0.00 0.00 0.00 0.00
6.00 0.00 0 0.00 0.00 0.00 0.00
7.00 0.00 0 0.00 0.00 0.00 0.00
8.00 0.00 0 0.00 0.00 0.00 0.00
9.00 0.00 0 0.00 0.00 0.00 0.00
10.00 0.00 0 0.00 0.00 0.00 0.00
11.00 0.01 14 0.03 0.00 0.00 0.00
12.00 0.70 706 1.23 0.01 0.00 0.00
13.00 0.05 1,095 1.70 0.01 0.00 0.01
14.00 0.03 1,220 1.86 0.01 0.00 0.01
15.00 0.03 1,298 1.95 0.01 0.00 0.01
16.00 0.02 1,352 2.02 0.01 0.00 0.01
17.00 0.02 1,371 2.05 0.02 0.00 0.02
18.00 0.02 1,371 2.05 0.02 0.00 0.02
19.00 0.01 1,368 2.04 0.02 0.00 0.01
20.00 0.01 1,364 2.04 0.01 0.00 0.01
21.00 0.01 1,360 2.03 0.01 0.00 0.01
22.00 0.01 1,357 2.03 0.01 0.00 0.01
23.00 0.01 1,355 2.02 0.01 0.00 0.01
24.00 0.01 1,352 2.02 0.01 0.00 0.01
25.00 0.00 1,320 1.98 0.01 0.00 0.01
26.00 0.00 1,289 1.94 0.01 0.00 0.01
27.00 0.00 1,259 1.90 0.01 0.00 0.01
28.00 0.00 1,228 1.87 0.01 0.00 0.01
29.00 0.00 1,199 1.83 0.01 0.00 0.01
30.00 0.00 1,170 1.79 0.01 0.00 0.01

Mars Hill University Student Center, 10-yr Storm Detention (Po Type Il 24-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 8
Stage-Discharge for Pond 1 P: StormTech Detention
Elevation Discharge Discarded Primary Elevation Discharge Discarded Primary
(feet) (cfs) (cfs) (cfs) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0.00 0.00 5.20 16.37 0.00 16.37
0.10 0.00 0.00 0.00 5.30 16.59 0.00 16.59
0.20 0.00 0.00 0.00 5.40 16.80 0.00 16.80
0.30 0.00 0.00 0.00 5.50 17.02 0.00 17.02
0.40 0.00 0.00 0.00
0.50 0.00 0.00 0.00
0.60 0.00 0.00 0.00
0.70 0.00 0.00 0.00
0.80 0.00 0.00 0.00
0.90 0.00 0.00 0.00
1.00 0.00 0.00 0.00
1.10 0.01 0.00 0.00
1.20 0.01 0.00 0.00
1.30 0.01 0.00 0.00
1.40 0.01 0.00 0.01
1.50 0.01 0.00 0.01
1.60 0.01 0.00 0.01
1.70 0.01 0.00 0.01
1.80 0.01 0.00 0.01
1.90 0.01 0.00 0.01
2.00 0.01 0.00 0.01
2.10 0.04 0.00 0.04
2.20 0.14 0.00 0.14
2.30 0.29 0.00 0.29
2.40 0.48 0.00 0.48
2.50 0.69 0.00 0.68
2.60 0.88 0.00 0.88
2.70 1.03 0.00 1.03
2.80 1.16 0.00 1.16
2.90 1.28 0.00 1.27
3.00 1.38 0.00 1.38
3.10 1.90 0.00 1.90
3.20 2.79 0.00 2.79
3.30 3.94 0.00 3.94
3.40 5.31 0.00 5.31
3.50 6.89 0.00 6.89
3.60 8.67 0.00 8.66
3.70 10.64 0.00 10.63
3.80 12.79 0.00 12.79
3.90 13.18 0.00 13.18
4.00 13.45 0.00 13.45
4.10 13.72 0.00 13.72
4.20 13.98 0.00 13.98
4.30 14.24 0.00 14.24
4.40 14.49 0.00 14.49
4.50 14.74 0.00 14.74
4.60 14.98 0.00 14.98
4.70 15.22 0.00 15.22
4.80 15.46 0.00 15.46
4.90 15.69 0.00 15.69
5.00 15.92 0.00 15.92
5.10 16.15 0.00 16.14

Mars Hill University Student Center, 10-yr Storm Detention (Po Type 1124-hr Rainfall=3.96"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 9
Stage-Area-Storage for Pond 1 P: StormTech Detention
Elevation Surface Storage Elevation Surface Storage
(feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet)
0.00 1,029 0 5.20 1,029 3,266
0.10 1,029 41 5.30 1,029 3,308
0.20 1,029 82 5.40 1,029 3,349
0.30 1,029 123 5.50 1,029 3,390
0.40 1,029 165
0.50 1,029 206
0.60 1,029 247
0.70 1,029 288
0.80 1,029 351
0.90 1,029 435
1.00 1,029 518
1.10 1,029 602
1.20 1,029 685
1.30 1,029 768
1.40 1,029 850
1.50 1,029 932
1.60 1,029 1,014
1.70 1,029 1,095
1.80 1,029 1,175
1.90 1,029 1,256
2.00 1,029 1,335
2.10 1,029 1,415
2.20 1,029 1,493
2.30 1,029 1,571
2.40 1,029 1,648
2.50 1,029 1,725
2.60 1,029 1,801
2.70 1,029 1,876
2.80 1,029 1,950
2.90 1,029 2,023
3.00 1,029 2,096
3.10 1,029 2,167
3.20 1,029 2,237
3.30 1,029 2,306
3.40 1,029 2,374
3.50 1,029 2,440
3.60 1,029 2,505
3.70 1,029 2,568
3.80 1,029 2,629
3.90 1,029 2,689
4.00 1,029 2,745
4.10 1,029 2,798
4.20 1,029 2,847
4.30 1,029 2,893
4.40 1,029 2,936
4.50 1,029 2,978
4.60 1,029 3,020
4.70 1,029 3,061
4.80 1,029 3,102
4.90 1,029 3,143
5.00 1,029 3,184
5.10 1,029 3,225

Mars Hill University Student Center, 25-yr Storm (Pre-Constn) Type 11 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1S: Runoff
Mars Hill University Student Center, 25-yr. Storm Event (Pre-Construction)
[49] Hint: Tc<2dt may require smaller dt
Runoff = 0.40 cfs @ 11.99 hrs, Volume= 0.022 af, Depth= 0.79"
Routed to nonexistent node 1 P
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs
Type II 24-hr Rainfall=4.72"
Area (ac) CN Description
0.233 61 >75% Grass cover, Good, HSG B
0.099 39 >75% Grass cover, Good, HSG A
0.332 54 Weighted Average
0.332 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.7 75 0.0200 0.22 Lag/CN Method,
Subcatchment 1S: Runoff
Hydrograph
__I__J__L__I-_ - 1 I 1 L I J L I " I
1 ' I 1
-r I 1 1 1 I I I 1 I I I I I
0.44:' . + r r , - ❑Runoff`
I 1 I I 1 I I 1 I I 1 I I 1 1 I
0.42: ,r--1--1--r--1- 1o40ds1 -1 1 r I -, r 1 I 1 r I r r I 1 T r
0.4:'- 1 1 I 1 1 1 1 I 1 I I 1
I i I I I I I I i I Type II24-her
0.38-' 1 _1__L_ J__ 1 L 1 J L I 1 L I
1 1 I 1 1 1 1 1 1 1 I I I
0.36 --1---.-- --I--±--. 'I +--1---I---1--}--1---1--i--. Rainfall=4.72"
- 1 1 I I 1 I ` I 1 `
0.3tk 1 i r 1 -1--T ---4--r--1------Ir-- I
0.32 I I I I 1 1 Runoff Area=0.332 ac
1 I I
0.3= r--1__J__L__1___
- I I 1 1 Ilii
0.28 _- 1--1 -1' I / _-H--r--I-_- • Runoff Volume=0.022-af
0.26'
( I--i--r--1---1 1 r I
13 024_ I 1 1 1 1 - Runoff-Depth=0.79 ' -
• I 1 1 I I I I I 1
`$ 0.22-' -_I__J__L_ _-_J__._ • 1 L 1 -1 L
LT• 0.2 '' -I- , I- I 1- , Flow Length=75
I 1 1 1 1 I 1
0:16] r ; Slope=0.0200 '/'
p , I I I I I 1 I I I I I I I I
0.14-3' j -_1-_J__L__1__J-_ 1 L I -1 L 1 _ I
, I 1 I 1 I 1 1 I Tc=5.7 .min-
7 ,0.12i I 1 I 1 1 1 1 1 1 1 1 1
0.1 r 1 1 r I 1 r I 1 r 1 1 r 1 l
0.08i" I I 1 1 I I 1 1 I I 1 I I CN54 _
I I 1 1 I 1 I 1 I 1 tilt 1
0.08= --I-_J__L__1__J__ __L_ I__.4L 1 4
L I J I 1 I-__
0.04i' ,
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Time (hours)

Mars Hill University Student Center, 25-yr Storm (Pre-Constn) Type II 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: Runoff
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
5.00 0.30 0.00 0.00 18.00 4.35 0.63 0.01
5.25 0.32 0.00 0.00 18.25 4.37 0.63 0.01
5.50 0.34 0.00 0.00 18.50 4.39 0.64 0.01
5.75 0.36 0.00 0.00 18.75 4.41 0.65 0.01
6.00 0.38 0.00 0.00 19.00 4.43 0.66 0.01
6.25 0.40 0.00 0.00 19.25 4.44 0.67 0.01
6.50 0.42 0.00 0.00 19.50 4.46 0.67 0.01
6.75 0.44 0.00 0.00 19.75 4.48 0.68 0.01
7.00 0.47 0.00 0.00 20.00 4.49 0.69 0.01
7.25 0.49 0.00 0.00 20.25 4.51 0.69 0.01
7.50 0.52 0.00 0.00 20.50 4.52 0.70 0.01
7.75 0.54 0.00 0.00 20.75 4.54 0.71 0.01
8.00 0.57 0.00 0.00 21.00 4.55 0.71 0.01
8.25 0.59 0.00 0.00 21.25 4.57 0.72 0.01
8.50 0.62 0.00 0.00 21.50 4.58 0.73 0.01
8.75 0.66 0.00 0.00 21.75 4.60 0.73 0.01
9.00 0.69 0.00 0.00 22.00 4.61 0.74 0.01
9.25 0.73 0.00 0.00 22.25 4.63 0.75 0.01
9.50 0.77 0.00 0.00 22.50 4.64 0.75 0.01
9.75 0.81 0.00 0.00 22.75 4.65 0.76 0.01
10.00 0.85 0.00 0.00 23.00 4.67 0.76 0.01
10.25 0.91 0.00 0.00 23.25 4.68 0.77 0.01
10.50 0.96 0.00 0.00 23.50 4.69 0.78 0.01
10.75 1.03 0.00 0.00 23.75 4.71 0.78 0.01
11.00 1.11 0.00 0.00 24.00 4.72 0.79 0.01
11.25 1.21 0.00 0.00 24.25 4.72 0.79 0.00
11.50 1.34 0.00 0.00 24.50 4.72 0.79 0.00
11.75 1.83 0.00 0.00 24.75 4.72 0.79 0.00
12.00 3.13 0.20 0.39 25.00 4.72 0.79 0.00
12.25 3.33 0.26 0.07 25.25 4.72 0.79 0.00
12.50 3.47 0.30 0.05 25.50 4.72 0.79 0.00
12.75 3.56 0.33 0.04 25.75 4.72 0.79 0.00
13.00 3.64 0.36 0.03 26.00 4.72 0.79 0.00
13.25 3.71 0.38 0.03 26.25 4.72 0.79 0.00
13.50 3.77 0.40 0.03 26.50 4.72 0.79 0.00
13.75 3.82 0.42 0.02 26.75 4.72 0.79 0.00
14.00 3.87 0.44 0.02 27.00 4.72 0.79 0.00
14.25 3.91 0.45 0.02 27.25 4.72 0.79 0.00
14.50 3.95 0.47 0.02 27.50 4.72 0.79 0.00
14.75 3.99 0.48 0.02 27.75 4.72 0.79 0.00
15.00 4.03 0.50 0.02 28.00 4.72 0.79 0.00
15.25 4.06 0.51 0.02 28.25 4.72 0.79 0.00
15.50 4.10 0.52 0.02 28.50 4.72 0.79 0.00
15.75 4.13 0.54 0.02 28.75 4.72 0.79 0.00
16.00 4.15 0.55 0.01 29.00 4.72 0.79 0.00
16.25 4.18 0.56 0.01 29.25 4.72 0.79 0.00
16.50 4.21 0.57 0.01 29.50 4.72 0.79 0.00
16.75 4.23 0.58 0.01 29.75 4.72 0.79 0.00
17.00 4.26 0.59 0.01 30.00 4.72 0.79 0.00
17.25 4.28 0.60 0.01
17.50 4.30 0.61 0.01
17.75 4.33 0.62 0.01

Mars Hill University Student Center, 25-yr Storm Detention (Po Type II 24-hr Rainfa11=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1 S: Runoff
Mars Hill University Student Center, 25-yr. Storm Event (Post-Construction)
[49] Hint: Tc<2dt may require smaller dt
Runoff = 1.37 cfs @ 11.94 hrs, Volume= 2,583 cf, Depth= 2.14"
Routed to Pond 1 P : StormTech Detention
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs
Type II 24-hr Rainfall=4.72"
Area (ac) CN Description
* 0.166 98 Pavement, Sidewalks, Roofs
0.083 61 >75% Grass cover, Good, HSG B
0.083 39 >75% Grass cover, Good, HSG A
0.332 74 Weighted Average
0.166 50.00% Pervious Area
0.166 50.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
3.4 75 0.0200 0.37 Lag/CN Method,
Subcatchment 1 S: Runoff
Hydrograph
©Runoff
I1.37 cfs I
Type II 24-hr
Rainfall=4.72"
.Runoff Area=0332
_ >.Y ac
Runoff Volurne=2,583 cf
`
Runoff Depth=2.14"
Flow Length=75'
Slope=0.0200 'I'
; ' Tc=3.4min
{ CN=74
-/,//////////////////✓ //4J!. ��®/®// /®/////////////®////// _.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Time (hours)

Mars Hill University Student Center, 25-yr Storm Detention (Po Type II 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: Runoff
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 26.00 4.72 2.14 0.00
0.50 0.02 0.00 0.00 26.50 4.72 2.14 0.00
1.00 0.05 0.00 0.00 27.00 4.72 2.14 0.00
1.50 0.08 0.00 0.00 27.50 4.72 2.14 0.00
2.00 0.10 0.00 0.00 28.00 4.72 2.14 0.00
2.50 0.13 0.00 0.00 28.50 4.72 2.14 0.00
3.00 0.16 0.00 0.00 29.00 4.72 2.14 0.00
3.50 0.19 0.00 0.00 29.50 4.72 2.14 0.00
4.00 0.23 0.00 0.00 30.00 4.72 2.14 0.00
4.50 0.26 0.00 0.00
5.00 0.30 0.00 0.00
5.50 0.34 0.00 0.00
6.00 0.38 0.00 0.00
6.50 0.42 0.00 0.00
7.00 0.47 0.00 0.00
7.50 0.52 0.00 0.00
8.00 0.57 0.00 0.00
8.50 0.62 0.00 0.00
9.00 0.69 0.00 0.00
9.50 0.77 0.00 0.00
10.00 0.85 0.01 0.00
10.50 0.96 0.02 0.01
11.00 1.11 0.04 0.02
11.50 1.34 0.10 0.05
12.00 3.13 0.99 0.94
12.50 3.47 1.22 0.11
13.00 3.64 1.34 0.07
13.50 3.77 1.43 0.05
14.00 3.87 1.50 0.04
14.50 3.95 1.56 0.04
15.00 4.03 1.62 0.04
15.50 4.10 1.67 0.03
16.00 4.15 1.71 0.03
16.50 4.21 1.75 0.03
17.00 4.26 1.79 0.02
17.50 4.30 1.82 0.02
18.00 4.35 1.86 0.02
18.50 4.39 1.89 0.02
19.00 4.43 1.92 0.02
19.50 4.46 1.94 0.02
20.00 4.49 1.97 0.02
20.50 4.52 1.99 0.02
21.00 4.55 2.01 0.02
21.50 4.58 2.04 0.02
22.00 4.61 2.06 0.01
22.50 4.64 2.08 0.01
23.00 4.67 2.10 0.01
23.50 4.69 2.12 0.01
24.00 4.72 2.14 0.01
24.50 4.72 2.14 0.00
25.00 4.72 2.14 0.00
25.50 4.72 2.14 0.00

Mars Hill University Student Center, 25-yr Storm Detention (Po Type II 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Pace 3
Summary for Pond 1 P: StormTech Detention
Detention Pond
Inflow Area = 14,462 sf, 50.00% Impervious, Inflow Depth = 2.14"
Inflow = 1.37 cfs @ 11.94 hrs, Volume= 2,583 cf
Outflow = 0.08 cfs @ 12.92 hrs, Volume= 1,406 cf, Atten= 95%, Lag= 58.7 min
Discarded = 0.00 cfs @ 10.65 hrs, Volume= 102 cf
Primary = 0.07 cfs @ 12.92 hrs, Volume= 1,304 cf
Routed to nonexistent node 1 R
Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs
Peak Elev= 2.14' @ 12.92 hrs Surf.Area= 1,029 sf Storage= 1,443 cf
Plug-Flow detention time= 356.9 min calculated for 1,403 cf (54% of inflow)
Center-of-Mass det. time= 235.1 min ( 1,069.7 - 834.6 )
Volume Invert Avail.Storage Storage Description
#1A 0.00' 1,511 cf 29.92'W x 34.38'L x 5.50'H Field A
5,657 cf Overall - 1,878 cf Embedded = 3,779 cf x 40.0% Voids
#2A 0.75' 1,878 cf ADS_StormTech MC-3500 d +Cap x 16 Inside#1
Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf
Overall Size= 77.0"W x 45.0"H x 7.50'L with 0.33' Overlap
16 Chambers in 4 Rows
Cap Storage= 14.9 cf x 2 x 4 rows = 119.2 cf
3,390 cf Total Available Storage
Storage Group A created with Chamber Wizard
Device Routing Invert Outlet Devices
#1 Primary 0.75' 18.00" Vert. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#2 Device 1 0.75' 0.50" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#3 Device 1 2.00' 8.00" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#4 Device 1 3.00' 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
0.5' Crest Height
#5 Discarded 0.00' 0.060 in/hr Exfiltration over Surface area Phase-In= 0.01'
Discarded OutFlow Max=0.00 cfs @ 10.65 hrs HW=0.06' (Free Discharge)
L5=Exfiltration (Exfiltration Controls 0.00 cfs)
Primary OutFlow Max=0.07 cfs @ 12.92 hrs HW=2.14' (Free Discharge)
L1=Orifice/Grate (Passes 0.07 cfs of 6.84 cfs potential flow)
AL2=Orifice/Grate (Orifice Controls 0.01 cfs @ 5.63 fps)
3=Orifice/Grate (Orifice Controls 0.06 cfs @ 1.26 fps)
4=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)

Mars Hill University Student Center, 25-yr Storm Detention (Po Type II 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 4
Pond 1 P: StormTech Detention - Chamber Wizard Field A
Chamber Model =ADS_StormTech MC-3500 d +Cap(ADS StormTech®MC-3500 d rev 03/14 with Cap
volume)
Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf
Overall Size= 77.0"W x 45.0'H x 7.50'L with 0.33' Overlap
Cap Storage= 14.9 cf x 2 x 4 rows = 119.2 cf
77.0" Wide + 9.0" Spacing = 86.0" C-C Row Spacing
4 Chambers/Row x 7.17' Long +1.85' Cap Length x 2 = 32.38' Row Length +12.0" End Stone x 2 = 34.38'
Base Length
4 Rows x 77.0" Wide + 9.0" Spacing x 3 + 12.0" Side Stone x 2 = 29.92' Base Width
9.0" Stone Base + 45.0" Chamber Height + 12.0" Stone Cover = 5.50' Field Height
16 Chambers x 110.0 cf + 14.9 cf Cap Volume x 2 x 4 Rows = 1,878.4 cf Chamber Storage
5,656.9 cf Field - 1,878.4 cf Chambers = 3,778.5 cf Stone x 40.0% Voids = 1,511.4 cf Stone Storage
Chamber Storage + Stone Storage = 3,389.8 cf = 0.078 of
Overall Storage Efficiency = 59.9%
Overall System Size = 34.38' x 29.92' x 5.50'
16 Chambers
209.5 cy Field
139.9 cy Stone

Mars Hill University Student Center, 25-yr Storm Detention (Po Type II 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 5
Pond 1 P: StormTech Detention
Hydrograph
■Inflow
/// 1.37 cfs 1 ❑Outflow
Inflow Area=14,462 sf ElP is maryed
Peak Elev=2.14'
Storage=1 ,443 cf
N
U
O
LL
0.08 cfs
ciei 40/7 //// %////////////
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Time (hours)
Pond 1 P: StormTech Detention
Stage-Discharge
El Total
j CIDi Discardedar
y
5 j /
j •
/_/
4-
% �
ate, //�� Sharp-Crested Rectangular Weir
c 3 o - -
10
Orifice/Grate;
2 /
r
/�/40
Orifice/Grate+Orifice/Grate
/ Exfiltration /
0 2 4 6 8 10 12 14 16
Discharge (cfs)

Mars Hill University Student Center, 25-yr Storm Detention (Po Type II 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 6
Pond 1 P: StormTech Detention
Stage-Area-Storage
Surface/Horizontal/Wetted Area(sq-ft)
0 100 200 300 400 500 600 700 800 900 1,000 ❑Surface`
Storage 1
•
5 4
,
erd
4 IAfff
/
/ 0
r
///
C 3 ///
o - II //
CU
//
dII /// I I ,
w 2_ III// r
// j
1 [A5S13SEaii'I'Oh�f,�(`i50b d` p1
I I I
— —--- lRleid Ai-
0 500 1,000 1,500 2,000 2,500 3,000
Storage(cubic-feet)

Mars Hill University Student Center, 25-yr Storm Detention (Po Type 11 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 7
Hydrograph for Pond 1 P: StormTech Detention
Time Inflow Storage Elevation Outflow Discarded Primary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 0.00 0.00 0.00 0.00
1.00 0.00 0 0.00 0.00 0.00 0.00
2.00 0.00 0 0.00 0.00 0.00 0.00
3.00 0.00 0 0.00 0.00 0.00 0.00
4.00 0.00 0 0.00 0.00 0.00 0.00
5.00 0.00 0 0.00 0.00 0.00 0.00
6.00 0.00 0 0.00 0.00 0.00 0.00
7.00 0.00 0 0.00 0.00 0.00 0.00
8.00 0.00 0 0.00 0.00 0.00 0.00
9.00 0.00 0 0.00 0.00 0.00 0.00
10.00 0.00 6 0.02 0.00 0.00 0.00
11.00 0.02 43 0.10 0.00 0.00 0.00
12.00 0.94 1,041 1.63 0.01 0.00 0.01
13.00 0.07 1,443 2.14 0.07 0.00 0.07
14.00 0.04 1,418 2.10 0.05 0.00 0.05
15.00 0.04 1,406 2.09 0.04 0.00 0.04
16.00 0.03 1,396 2.08 0.03 0.00 0.03
17.00 0.02 1,388 2.07 0.03 0.00 0.02
18.00 0.02 1,382 2.06 0.02 0.00 0.02
19.00 0.02 1,376 2.05 0.02 0.00 0.02
20.00 0.02 1,371 2.04 0.02 0.00 0.02
21.00 0.02 1,368 2.04 0.02 0.00 0.01
22.00 0.01 1,366 2.04 0.02 0.00 0.01
23.00 0.01 1,365 2.04 0.01 0.00 0.01
24.00 0.01 1,364 2.04 0.01 0.00 0.01
25.00 0.00 1,329 1.99 0.01 0.00 0.01
26.00 0.00 1,298 1.95 0.01 0.00 0.01
27.00 0.00 1,267 1.91 0.01 0.00 0.01
28.00 0.00 1,237 1.88 0.01 0.00 0.01
29.00 0.00 1,207 1.84 0.01 0.00 0.01
30.00 0.00 1,178 1.80 0.01 0.00 0.01

Mars Hill University Student Center, 25-yr Storm Detention (Po Type II 24-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD® 10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 8
Stage-Discharge for Pond 1 P: StormTech Detention
Elevation Discharge Discarded Primary Elevation Discharge Discarded Primary
(feet) (cfs) (cfs) (cfs) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0.00 0.00 5.20 16.37 0.00 16.37
0.10 0.00 0.00 0.00 5.30 16.59 0.00 16.59
0.20 0.00 0.00 0.00 5.40 16.80 0.00 16.80
0.30 0.00 0.00 0.00 5.50 17.02 0.00 17.02
0.40 0.00 0.00 0.00
0.50 0.00 0.00 0.00
0.60 0.00 0.00 0.00
0.70 0.00 0.00 0.00
0.80 0.00 0.00 0.00
0.90 0.00 0.00 0.00
1.00 0.00 0.00 0.00
1.10 0.01 0.00 0.00
1.20 0.01 0.00 0.00
1.30 0.01 0.00 0.00
1.40 0.01 0.00 0.01
1.50 0.01 0.00 0.01
1.60 0.01 0.00 0.01
1.70 0.01 0.00 0.01
1.80 0.01 0.00 0.01
1.90 0.01 0.00 0.01
2.00 0.01 0.00 0.01
2.10 0.04 0.00 0.04
2.20 0.14 0.00 0.14
2.30 0.29 0.00 0.29
2.40 0.48 0.00 0.48
2.50 0.69 0.00 0.68
2.60 0.88 0.00 0.88
2.70 1.03 0.00 1.03
2.80 1.16 0.00 1.16
2.90 1.28 0.00 1.27
3.00 1.38 0.00 1.38
3.10 1.90 0.00 1.90
3.20 2.79 0.00 2.79
3.30 3.94 0.00 3.94
3.40 5.31 0.00 5.31
3.50 6.89 0.00 6.89
3.60 8.67 0.00 8.66
3.70 10.64 0.00 10.63
3.80 12.79 0.00 12.79
3.90 13.18 0.00 13.18
4.00 13.45 0.00 13.45
4.10 13.72 0.00 13.72
4.20 13.98 0.00 13.98
4.30 14.24 0.00 14.24
4.40 14.49 0.00 14.49
4.50 14.74 0.00 14.74
4.60 14.98 0.00 14.98
4.70 15.22 0.00 15.22
4.80 15.46 0.00 15.46
4.90 15.69 0.00 15.69
5.00 15.92 0.00 15.92
5.10 16.15 0.00 16.14

Mars Hill University Student Center, 25-yr Storm Detention (Po Type 1124-hr Rainfall=4.72"
Prepared by Davis Civil Solutions P A Printed 8/13/2024
HydroCAD®10.20-5b s/n 03655 ©2023 HydroCAD Software Solutions LLC Page 9
Stage-Area-Storage for Pond 1 P: StormTech Detention
Elevation Surface Storage Elevation Surface Storage
(feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet)
0.00 1,029 0 5.20 1,029 3,266
0.10 1,029 41 5.30 1,029 3,308
0.20 1,029 82 5.40 1,029 3,349
0.30 1,029 123 5.50 1,029 3,390
0.40 1,029 165
0.50 1,029 206
0.60 1,029 247
0.70 1,029 288
0.80 1,029 351
0.90 1,029 435
1.00 1,029 518
1.10 1,029 602
1.20 1,029 685
1.30 1,029 768
1.40 1,029 850
1.50 1,029 932
1.60 1,029 1,014
1.70 1,029 1,095
1.80 1,029 1,175
1.90 1,029 1,256
2.00 1,029 1,335
2.10 1,029 1,415
2.20 1,029 1,493
2.30 1,029 1,571
2.40 1,029 1,648
2.50 1,029 1,725
2.60 1,029 1,801
2.70 1,029 1,876
2.80 1,029 1,950
2.90 1,029 2,023
3.00 1,029 2,096
3.10 1,029 2,167
3.20 1,029 2,237
3.30 1,029 2,306
3.40 1,029 2,374
3.50 1,029 2,440
3.60 1,029 2,505
3.70 1,029 2,568
3.80 1,029 2,629
3.90 1,029 2,689
4.00 1,029 2,745
4.10 1,029 2,798
4.20 1,029 2,847
4.30 1,029 2,893
4.40 1,029 2,936
4.50 1,029 2,978
4.60 1,029 3,020
4.70 1,029 3,061
4.80 1,029 3,102
4.90 1,029 3,143
5.00 1,029 3,184
5.10 1,029 3,225

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Soil Map—Madison County,North Carolina Mars Hill University Student Center
Map Unit Legend
Map Unit Symbol Map Unit Name Acres In A01 Percent of AOI
CxC Clifton-Urban land complex,2 1.4 44.9%
to 15 percent slopes
UhE Udorthents-Urban land 1.7 55.1%
complex,2 to 50 percent
slopes
Totals for Area of Interest 3.1 100.0%
USDA Natural Resources Web Soil Survey 8/13/2024
m Conservation Service National Cooperative Soil Survey Page 3 of 3