Planning & Zoning Commission (linked)

259 Noank Ledyard Road 
 
Page | 1  
Mystic, CT  06355 
 
 
 
150 BUTLERTOWN ROAD SUBDIVISION APPLICATION 
STORM WATER MANAGEMENT REPORT 
March 11, 2025 
 
The 150 Butlertown Road Subdivision project involves an existing 33.52 acre parcel – Parcel Map/Lot 37-
1278 – located on the southwestern side of Butlertown Road in the northwest section of Waterford, 
Connecticut.  The parcel is proposed to be partially developed as a subdivision under the Town of 
Waterford Zoning and Subdivision Regulations taking the existing lot and creating a new building lot (Lot 
A) 5.67 acres in area. The remainder of the parcel will remain as it is presently with woodlands, wetlands 
and the existing single-family residential structure – 150 Butlertown Road. As part of the Final 
Subdivision Plan Application requirements listed in Section 25.6 of the Waterford Zoning Regulations 
and Section 5.5 of the Waterford Subdivision Regulations, this Storm Water Management Report 
establishes the means for mitigating the increase in storm water runoff and provides treatment capacity 
consistent with the Connecticut Storm Water Management Plan and other pertinent regulations and 
best management practices.  
 
The 150 Butlertown Road Subdivision parcel is located within the Oil Mill Brook subregional drainage 
basin which drains directly to the Niantic River, Niantic Bay and Long Island Sound. The delineation of 
the subregional basin is shown in Figure 1. The total area of the subregional basin is 5.2 mi2; The 150 
Butlertown Road Subdivision parcel accounts for 33.52 acres of the basin. Excluding the Open Space 
area of the 150 Butlertown Road Subdivision the development impacts 5.67 acres of the Oil Mill Brook 
basin; approximately 0.17% of the total basin. The basin consists primarily of residential lots of varying 
size, roadways (including Interstates 395 and 95), agricultural land, a racetrack, limited commercial and 
municipal uses, open space and woodlands.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
259 Noank Ledyard Road 
 
Page | 2  
Mystic, CT  06355 
 
 
 
The 150 Butlertown Road Subdivision parcel and the development area consists of one primary drainage 
area. The wetlands (Poly Brook) at the eastern end of the parcel drain directly to Oil Mill Brook 
downstream of Lake Konomoc. Currently, the 150 Butlertown Road parcel is primarily woodlands and 
wetlands with only 1.40 acres in the central portion developed with a single-family home. The proposed 
subdivision would consist of the development of another single-family residential lot on the western 
side of the wetlands impacting a 5.52 acre drainage basin. These conditions, along with the land survey 
data from the subdivision site plan set were used to develop a HydroCAD model representing the 
existing conditions and project storm water runoff flows for various storm events using the USDA 
Natural Resources Conservation Service (NRCS) TR-20 method. The results of the model are summarized 
in Figure 2. The full HydroCAD report is attached for reference as Attachment A. 
 
 
Summary of Storm Water Runoff Flow Rates (ft3/s) 
150 Butlertown Road Subdivision 
Existing Conditions 
Source: HydroCAD 
Storm Event 
Total 
 1 year Storm 
0.07 
2 year Storm 
0.21 
10 year Storm 
0.78 
25 year Storm 
1.11 
100 year Storm 
1.89 
 
The 150 Butlertown Road parcel was then modeled under the land use conditions proposed within the 
developed area as depicted in the Final Subdivision Application package and site plan set, again, using 
HydroCAD and the TR-20 methodology.  
 
The proposed development consists of adding one single-unit residential building lot (Lot A), 5.67 acres 
in size, with an extended gravel driveway that connects with the existing driveway for 150 Butlertown 
Road and utilizes the existing wetland crossing/bridge. Three small detention basins (#1A, #1B and #1C) 
are proposed flanking the proposed Lot A driveway to intercept runoff from the up-gradient woodland 
area and the proposed development for treatment and peak runoff flow mitigation. Each basin is sized 
and configured per the site plan set and includes a catch basin overflow and discharge pipe to the down-
gradient woodland area. Discharges are further protected with riprap aprons for energy dissipation. Two 
cross-culverts are proposed to convey runoff through the driveway discharging to detention basins #1B 
and #1C. Total stormwater detention or storage volume is 26,748 ft3 – Detention Basin #1A – 13,488 ft3; 
Detention Basin #1B – 7,140 ft3; and Detention Basin #1C – 6,120 ft3. Each of the drainage basin areas 
for each detention basin under proposed conditions is delineated on the Erosion & Sediment Control 
and Storm Water Management Plan sheet within the Final Subdivision Application site plan set. A 
Figure 2: Storm Water Runoff Flow Rates – Existing Conditions 

 
259 Noank Ledyard Road 
 
Page | 3  
Mystic, CT  06355 
 
 
 
summary of the storm water runoff flow rates under the proposed developed condition is presented in 
Figure 3. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
The storm water runoff flow rates under the proposed conditions represent a zero net increase 
compared to existing conditions. A comparison of the existing and proposed storm water runoff flow 
rates for all storms is presented in Figure 4. Attachment B provides all the HydroCAD data reports for the 
proposed conditions model. The increase in storm water runoff flow rates due to the introduction of 
impervious surfaces and lawn/landscaped areas within the developed portion of the parcel are 
mitigated by the detention basin storage and treatment capacity.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
From a storm water treatment perspective, the Water Quality Volume was calculated for the 150 
Butlertown Road Subdivision under proposed conditions and included as part of the Erosion & Sediment 
Control and Storm Water Management Plan sheet and the Final Subdivision Application package. The 
Water Quality Volume was calculated per the 2024 Connecticut Stormwater Quality Manual for the 
development area and determined to be a total of 3,118 ft3. The proposed stormwater detention basin 
Figure 3: Storm Water Runoff Flow Rates – Proposed Conditions 
Figure 4: Storm Water Runoff Flow Rates Comparison 

 
259 Noank Ledyard Road 
 
Page | 4  
Mystic, CT  06355 
 
 
 
provides 26,748 ft3 of treatment capacity exceeding and effectively treating the calculated Water 
Quality Volume. The three stormwater detention basins are designed to accept and direct the 
stormwater flows from the developed area and Lot A and under extreme storm events discharge their 
overflow to the down-gradient woodlands at flow rates less than existing conditions. Peak flows will be 
treated, mitigated and delayed eliminating any adverse impact to the greater watershed, wetland area 
and watercourses downstream.  
 
In conclusion, the impact of the 150 Butlertown Road Subdivision demonstrates a zero net increase in 
storm water flow rates while introducing storm water treatment with the implementation of 
strategically placed stormwater detention basins. Further, the detention basins are designed to target 
the impervious surfaces introduced with the proposed subdivision and provide direct flow mitigation 
and water treatment. These actions will mitigate the potential adverse impacts of the proposed 
subdivision on the remainder of the parcel dedicated to open space, the wetland and watercourses 
downstream of the development and all neighboring properties.  
 
Respectfully submitted, 
 
 
 
 
David L. Cooley, P.E. 
DLC Engineering Services, LLC 
 
Attachments 
Attachment A – HydroCAD Report – Existing Conditions 
Attachment B – HydroCAD Report – Proposed Conditions 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
259 Noank Ledyard Road 
 
Page | 5  
Mystic, CT  06355 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
ATTACHMENT A 
HydroCAD Report – Existing Conditions 
 
 
 
 
 
 
 
 

Table of Contents
Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
TABLE OF CONTENTS
Project Reports
   1   Rainfall Events Listing
   2   Area Listing (selected nodes)
   3   Ground Covers (selected nodes)
1-yr Event
   4   Subcat 1S: Drainage Area #1
2-yr Event
   5   Subcat 1S: Drainage Area #1
10-yr Event
   6   Subcat 1S: Drainage Area #1
25-yr Event
   7   Subcat 1S: Drainage Area #1
100-yr Event
   8   Subcat 1S: Drainage Area #1

Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
Page 1
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Rainfall Events Listing
Event#
Event
Name
Storm Type
Curve
Mode
Duration
(hours)
B/B
Depth
(inches)
AMC
1
1-yr
Type III 24-hr
Default
24.00
1
2.70
2
2
2-yr
Type III 24-hr
Default
24.00
1
3.40
2
3
10-yr
Type III 24-hr
Default
24.00
1
5.00
2
4
25-yr
Type III 24-hr
Default
24.00
1
5.70
2
5
100-yr
Type III 24-hr
Default
24.00
1
7.10
2

Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
Page 2
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Area Listing (selected nodes)
Area
(acres)
CN
Description
(subcatchment-numbers)
5.524
55
Woods, Good, HSG B  (1S)
5.524
55
TOTAL AREA

Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
Page 3
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Ground Covers (selected nodes)
HSG-A
(acres)
HSG-B
(acres)
HSG-C
(acres)
HSG-D
(acres)
Other
(acres)
Total
(acres)
Ground
Cover
Subcatchment
Numbers
0.000
5.524
0.000
0.000
0.000
5.524
Woods, Good 1S
0.000
5.524
0.000
0.000
0.000
5.524
TOTAL 
AREA

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
Page 4
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Summary for Subcatchment 1S: Drainage Area #1
Runoff
=
0.07 cfs @ 17.80 hrs,  Volume=
0.056 af,  Depth> 0.12"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.01 hrs
Type III 24-hr  1-yr Rainfall=2.70"
Area (sf)
CN
Description
240,645
55
Woods, Good, HSG B
240,645
100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
253.4
100
0.0400
0.01
Sheet Flow, Sheet Flow
Woods: Dense underbrush   n= 0.800   P2= 0.04"
5.0
588
0.1563
1.98
Shallow Concentrated Flow, Shallow Conc Flow
Woodland   Kv= 5.0 fps
258.4
688
Total
Subcatchment 1S: Drainage Area #1
Runoff
Hydrograph
Time  (hours)
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Flow  (cfs)
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Type III 24-hr
1-yr Rainfall=2.70"
Runoff Area=240,645 sf
Runoff Volume=0.056 af
Runoff Depth>0.12"
Flow Length=688'
Tc=258.4 min
CN=55
0.07 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
Page 5
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Summary for Subcatchment 1S: Drainage Area #1
Runoff
=
0.21 cfs @ 16.66 hrs,  Volume=
0.144 af,  Depth> 0.31"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.01 hrs
Type III 24-hr  2-yr Rainfall=3.40"
Area (sf)
CN
Description
240,645
55
Woods, Good, HSG B
240,645
100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
253.4
100
0.0400
0.01
Sheet Flow, Sheet Flow
Woods: Dense underbrush   n= 0.800   P2= 0.04"
5.0
588
0.1563
1.98
Shallow Concentrated Flow, Shallow Conc Flow
Woodland   Kv= 5.0 fps
258.4
688
Total
Subcatchment 1S: Drainage Area #1
Runoff
Hydrograph
Time  (hours)
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Flow  (cfs)
0.23
0.22
0.21
0.2
0.19
0.18
0.17
0.16
0.15
0.14
0.13
0.12
0.11
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Type III 24-hr
2-yr Rainfall=3.40"
Runoff Area=240,645 sf
Runoff Volume=0.144 af
Runoff Depth>0.31"
Flow Length=688'
Tc=258.4 min
CN=55
0.21 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
Page 6
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Summary for Subcatchment 1S: Drainage Area #1
Runoff
=
0.78 cfs @ 16.08 hrs,  Volume=
0.451 af,  Depth> 0.98"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.01 hrs
Type III 24-hr  10-yr Rainfall=5.00"
Area (sf)
CN
Description
240,645
55
Woods, Good, HSG B
240,645
100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
253.4
100
0.0400
0.01
Sheet Flow, Sheet Flow
Woods: Dense underbrush   n= 0.800   P2= 0.04"
5.0
588
0.1563
1.98
Shallow Concentrated Flow, Shallow Conc Flow
Woodland   Kv= 5.0 fps
258.4
688
Total
Subcatchment 1S: Drainage Area #1
Runoff
Hydrograph
Time  (hours)
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Flow  (cfs)
0.85
0.8
0.75
0.7
0.65
0.6
0.55
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Type III 24-hr
10-yr Rainfall=5.00"
Runoff Area=240,645 sf
Runoff Volume=0.451 af
Runoff Depth>0.98"
Flow Length=688'
Tc=258.4 min
CN=55
0.78 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
Page 7
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Summary for Subcatchment 1S: Drainage Area #1
Runoff
=
1.11 cfs @ 15.80 hrs,  Volume=
0.621 af,  Depth> 1.35"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.01 hrs
Type III 24-hr  25-yr Rainfall=5.70"
Area (sf)
CN
Description
240,645
55
Woods, Good, HSG B
240,645
100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
253.4
100
0.0400
0.01
Sheet Flow, Sheet Flow
Woods: Dense underbrush   n= 0.800   P2= 0.04"
5.0
588
0.1563
1.98
Shallow Concentrated Flow, Shallow Conc Flow
Woodland   Kv= 5.0 fps
258.4
688
Total
Subcatchment 1S: Drainage Area #1
Runoff
Hydrograph
Time  (hours)
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Flow  (cfs)
1
0
Type III 24-hr
25-yr Rainfall=5.70"
Runoff Area=240,645 sf
Runoff Volume=0.621 af
Runoff Depth>1.35"
Flow Length=688'
Tc=258.4 min
CN=55
1.11 cfs

Type III 24-hr  100-yr Rainfall=7.10"
Butlertown Road.Existing Conditions.6.14.2024
  Printed  8/23/2024
Prepared by DLC Engineering Services, LLC
Page 8
HydroCAD® 10.20-5a  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Summary for Subcatchment 1S: Drainage Area #1
Runoff
=
1.89 cfs @ 15.79 hrs,  Volume=
1.007 af,  Depth> 2.19"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.01 hrs
Type III 24-hr  100-yr Rainfall=7.10"
Area (sf)
CN
Description
240,645
55
Woods, Good, HSG B
240,645
100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
253.4
100
0.0400
0.01
Sheet Flow, Sheet Flow
Woods: Dense underbrush   n= 0.800   P2= 0.04"
5.0
588
0.1563
1.98
Shallow Concentrated Flow, Shallow Conc Flow
Woodland   Kv= 5.0 fps
258.4
688
Total
Subcatchment 1S: Drainage Area #1
Runoff
Hydrograph
Time  (hours)
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Flow  (cfs)
2
1
0
Type III 24-hr
100-yr Rainfall=7.10"
Runoff Area=240,645 sf
Runoff Volume=1.007 af
Runoff Depth>2.19"
Flow Length=688'
Tc=258.4 min
CN=55
1.89 cfs

 
259 Noank Ledyard Road 
 
Page | 6  
Mystic, CT  06355 
 
 
 
 
 
 
 
 
 
 
ATTACHMENT B 
HydroCAD Report – Proposed Conditions 
 

Table of Contents
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
TABLE OF CONTENTS
Project Reports
   1   Routing Diagram
   2   Rainfall Events Listing
   3   Area Listing (all nodes)
   4   Soil Listing (all nodes)
   5   Ground Covers (all nodes)
   6   Pipe Listing (all nodes)
1-yr Event
   7   Node Listing
   8   Subcat 1S: Drainage Area #1C
   9   Subcat 3S: Drainage Area #1A
  10   Subcat 5S: Drainage Area #1B
  11   Reach 7R: Basin #1A Discharge
  12   Reach 8R: Basin #1B Discharge
  13   Reach 9R: Basin #1C Discharge
  14   Pond 2P: Detention Basin #1C
  15   Pond 4P: Detention Basin #1A
  16   Pond 6P: Detention Basin #1B
2-yr Event
  17   Node Listing
  18   Subcat 1S: Drainage Area #1C
  19   Subcat 3S: Drainage Area #1A
  20   Subcat 5S: Drainage Area #1B
  21   Reach 7R: Basin #1A Discharge
  22   Reach 8R: Basin #1B Discharge
  23   Reach 9R: Basin #1C Discharge
  24   Pond 2P: Detention Basin #1C
  25   Pond 4P: Detention Basin #1A
  26   Pond 6P: Detention Basin #1B
10-yr Event
  27   Node Listing
  28   Subcat 1S: Drainage Area #1C
  29   Subcat 3S: Drainage Area #1A
  30   Subcat 5S: Drainage Area #1B
  31   Reach 7R: Basin #1A Discharge
  32   Reach 8R: Basin #1B Discharge
  33   Reach 9R: Basin #1C Discharge
  34   Pond 2P: Detention Basin #1C
  35   Pond 4P: Detention Basin #1A
  36   Pond 6P: Detention Basin #1B
25-yr Event
  37   Node Listing
  38   Subcat 1S: Drainage Area #1C
  39   Subcat 3S: Drainage Area #1A
  40   Subcat 5S: Drainage Area #1B
  41   Reach 7R: Basin #1A Discharge
  42   Reach 8R: Basin #1B Discharge

Table of Contents
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
  43   Reach 9R: Basin #1C Discharge
  44   Pond 2P: Detention Basin #1C
  45   Pond 4P: Detention Basin #1A
  46   Pond 6P: Detention Basin #1B
100-yr Event
  47   Node Listing
  48   Subcat 1S: Drainage Area #1C
  49   Subcat 3S: Drainage Area #1A
  50   Subcat 5S: Drainage Area #1B
  51   Reach 7R: Basin #1A Discharge
  52   Reach 8R: Basin #1B Discharge
  53   Reach 9R: Basin #1C Discharge
  54   Pond 2P: Detention Basin #1C
  55   Pond 4P: Detention Basin #1A
  56   Pond 6P: Detention Basin #1B
Multi-Event Tables
  57   Subcat 1S: Drainage Area #1C
  58   Subcat 3S: Drainage Area #1A
  59   Subcat 5S: Drainage Area #1B
  60   Reach 7R: Basin #1A Discharge
  61   Reach 8R: Basin #1B Discharge
  62   Reach 9R: Basin #1C Discharge
  63   Pond 2P: Detention Basin #1C
  64   Pond 4P: Detention Basin #1A
  65   Pond 6P: Detention Basin #1B

1S
Drainage Area #1C
3S
Drainage Area #1A
5S
Drainage Area #1B
7R
Basin #1A Discharge
8R
Basin #1B Discharge
9R
Basin #1C Discharge
2P
Detention Basin #1C
4P
Detention Basin #1A
6P
Detention Basin #1B
Routing Diagram for Butlertown Road.Proposed Conditions.11.23.2024
Prepared by DLC Engineering Services, LLC,  Printed 12/19/2024
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcat
Reach
Pond
Link

Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 2
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Rainfall Events Listing
Event#
Event
Name
Storm Type
Curve
Mode
Duration
(hours)
B/B
Depth
(inches)
AMC
1
1-yr
Type III 24-hr
Default
24.00
1
2.70
2
2
2-yr
Type III 24-hr
Default
24.00
1
3.40
2
3
10-yr
Type III 24-hr
Default
24.00
1
5.00
2
4
25-yr
Type III 24-hr
Default
24.00
1
5.70
2
5
100-yr
Type III 24-hr
Default
24.00
1
7.10
2

Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 3
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Area Listing (all nodes)
Area
(acres)
CN
Description
(subcatchment-numbers)
1.184
61
>75% Grass cover, Good, HSG B  (1S, 3S, 5S)
0.444
96
Gravel surface, HSG B  (1S, 3S, 5S)
0.056
98
Unconnected roofs, HSG B  (3S)
3.808
55
Woods, Good, HSG B  (1S, 3S, 5S)
5.492
60
TOTAL AREA

Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 4
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Soil Listing (all nodes)
Area
(acres)
Soil
Group
Subcatchment
Numbers
0.000
HSG A
5.492
HSG B
1S, 3S, 5S
0.000
HSG C
0.000
HSG D
0.000
Other
5.492
TOTAL AREA

Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 5
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Ground Covers (all nodes)
HSG-A
(acres)
HSG-B
(acres)
HSG-C
(acres)
HSG-D
(acres)
Other
(acres)
Total
(acres)
Ground
Cover
Subcatchment
Numbers
0.000
1.184
0.000
0.000
0.000
1.184
>75% Grass cover, Good 1S, 3S, 
5S
0.000
0.444
0.000
0.000
0.000
0.444
Gravel surface
1S, 3S, 
5S
0.000
0.056
0.000
0.000
0.000
0.056
Unconnected roofs
3S
0.000
3.808
0.000
0.000
0.000
3.808
Woods, Good
1S, 3S, 
5S
0.000
5.492
0.000
0.000
0.000
5.492
TOTAL AREA

Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 6
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pipe Listing (all nodes)
Line#
Node
Number
In-Invert
(feet)
Out-Invert
(feet)
Length
(feet)
Slope
(ft/ft)
n
Width
(inches)
Diam/Height
(inches)
Inside-Fill
(inches)
Node
Name
1
1S
0.00
0.00
25.0
0.0800
0.020
0.0
24.0
0.0
2
7R
356.00
355.00
111.0
0.0090
0.020
0.0
18.0
0.0
3
8R
320.00
319.00
28.0
0.0357
0.020
0.0
18.0
0.0
4
9R
302.00
301.00
27.0
0.0370
0.020
0.0
18.0
0.0

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 7
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Time span=0.00-48.00 hrs, dt=0.01 hrs, 4801 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method  -  Pond routing by Stor-Ind method
Runoff Area=84,877 sf   0.00% Impervious   Runoff Depth=0.16"
Subcatchment 1S: Drainage Area #1C
   Flow Length=621'   Tc=257.8 min   CN=57   Runoff=0.04 cfs  0.026 af
Runoff Area=99,965 sf   2.45% Impervious   Runoff Depth=0.26"
Subcatchment 3S: Drainage Area #1A
   Flow Length=424'   Tc=234.9 min   CN=61   Runoff=0.08 cfs  0.049 af
Runoff Area=54,385 sf   0.00% Impervious   Runoff Depth=0.29"
Subcatchment 5S: Drainage Area #1B
   Flow Length=509'   Tc=219.2 min   CN=62   Runoff=0.05 cfs  0.030 af
Avg. Flow Depth=0.00'   Max Vel=0.00 fps   Inflow=0.00 cfs  0.000 af
Reach 7R: Basin #1A Discharge
18.0"  Round Pipe   n=0.020   L=111.0'   S=0.0090 '/'   Capacity=6.48 cfs   Outflow=0.00 cfs  0.000 af
Avg. Flow Depth=0.00'   Max Vel=0.00 fps   Inflow=0.00 cfs  0.000 af
Reach 8R: Basin #1B Discharge
18.0"  Round Pipe   n=0.020   L=28.0'   S=0.0357 '/'   Capacity=12.90 cfs   Outflow=0.00 cfs  0.000 af
Avg. Flow Depth=0.00'   Max Vel=0.00 fps   Inflow=0.00 cfs  0.000 af
Reach 9R: Basin #1C Discharge
18.0"  Round Pipe   n=0.020   L=27.0'   S=0.0370 '/'   Capacity=13.14 cfs   Outflow=0.00 cfs  0.000 af
Peak Elev=307.55'  Storage=1,149 cf   Inflow=0.04 cfs  0.026 af
Pond 2P: Detention Basin #1C
   Outflow=0.00 cfs  0.000 af
Peak Elev=361.25'  Storage=2,153 cf   Inflow=0.08 cfs  0.049 af
Pond 4P: Detention Basin #1A
   Outflow=0.00 cfs  0.000 af
Peak Elev=325.46'  Storage=1,295 cf   Inflow=0.05 cfs  0.030 af
Pond 6P: Detention Basin #1B
   Outflow=0.00 cfs  0.000 af
Total Runoff Area = 5.492 ac   Runoff Volume = 0.106 af   Average Runoff Depth = 0.23"
98.98% Pervious = 5.436 ac     1.02% Impervious = 0.056 ac

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 8
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 1S: Drainage Area #1C
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.04
0.038
0.036
0.034
0.032
0.03
0.028
0.026
0.024
0.022
0.02
0.018
0.016
0.014
0.012
0.01
0.008
0.006
0.004
0.002
0
Type III 24-hr
1-yr Rainfall=2.70"
Runoff Area=84,877 sf
Runoff Volume=0.026 af
Runoff Depth=0.16"
Flow Length=621'
Tc=257.8 min
CN=57
0.04 cfs

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 9
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 3S: Drainage Area #1A
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.085
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Type III 24-hr
1-yr Rainfall=2.70"
Runoff Area=99,965 sf
Runoff Volume=0.049 af
Runoff Depth=0.26"
Flow Length=424'
Tc=234.9 min
CN=61
0.08 cfs

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 10
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 5S: Drainage Area #1B
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Type III 24-hr
1-yr Rainfall=2.70"
Runoff Area=54,385 sf
Runoff Volume=0.030 af
Runoff Depth=0.29"
Flow Length=509'
Tc=219.2 min
CN=62
0.05 cfs

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 11
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 7R: Basin #1A Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
1
0
Inflow Area=2.295 ac
Avg. Flow Depth=0.00'
Max Vel=0.00 fps
18.0"
Round Pipe
n=0.020
L=111.0'
S=0.0090 '/'
Capacity=6.48 cfs
0.00 cfs
0.00 cfs

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 12
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 8R: Basin #1B Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
1
0
Inflow Area=1.249 ac
Avg. Flow Depth=0.00'
Max Vel=0.00 fps
18.0"
Round Pipe
n=0.020
L=28.0'
S=0.0357 '/'
Capacity=12.90 cfs
0.00 cfs
0.00 cfs

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 13
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 9R: Basin #1C Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
1
0
Inflow Area=1.949 ac
Avg. Flow Depth=0.00'
Max Vel=0.00 fps
18.0"
Round Pipe
n=0.020
L=27.0'
S=0.0370 '/'
Capacity=13.14 cfs
0.00 cfs
0.00 cfs

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 14
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 2P: Detention Basin #1C
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.04
0.038
0.036
0.034
0.032
0.03
0.028
0.026
0.024
0.022
0.02
0.018
0.016
0.014
0.012
0.01
0.008
0.006
0.004
0.002
0
Inflow Area=1.949 ac
Peak Elev=307.55'
Storage=1,149 cf
0.04 cfs
0.00 cfs

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 15
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 4P: Detention Basin #1A
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.085
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Inflow Area=2.295 ac
Peak Elev=361.25'
Storage=2,153 cf
0.08 cfs
0.00 cfs

Type III 24-hr  1-yr Rainfall=2.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 16
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 6P: Detention Basin #1B
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Inflow Area=1.249 ac
Peak Elev=325.46'
Storage=1,295 cf
0.05 cfs
0.00 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 17
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Time span=0.00-48.00 hrs, dt=0.01 hrs, 4801 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method  -  Pond routing by Stor-Ind method
Runoff Area=84,877 sf   0.00% Impervious   Runoff Depth=0.38"
Subcatchment 1S: Drainage Area #1C
   Flow Length=621'   Tc=257.8 min   CN=57   Runoff=0.10 cfs  0.062 af
Runoff Area=99,965 sf   2.45% Impervious   Runoff Depth=0.53"
Subcatchment 3S: Drainage Area #1A
   Flow Length=424'   Tc=234.9 min   CN=61   Runoff=0.18 cfs  0.101 af
Runoff Area=54,385 sf   0.00% Impervious   Runoff Depth=0.57"
Subcatchment 5S: Drainage Area #1B
   Flow Length=509'   Tc=219.2 min   CN=62   Runoff=0.11 cfs  0.059 af
Avg. Flow Depth=0.00'   Max Vel=0.00 fps   Inflow=0.00 cfs  0.000 af
Reach 7R: Basin #1A Discharge
18.0"  Round Pipe   n=0.020   L=111.0'   S=0.0090 '/'   Capacity=6.48 cfs   Outflow=0.00 cfs  0.000 af
Avg. Flow Depth=0.00'   Max Vel=0.00 fps   Inflow=0.00 cfs  0.000 af
Reach 8R: Basin #1B Discharge
18.0"  Round Pipe   n=0.020   L=28.0'   S=0.0357 '/'   Capacity=12.90 cfs   Outflow=0.00 cfs  0.000 af
Avg. Flow Depth=0.00'   Max Vel=0.00 fps   Inflow=0.00 cfs  0.000 af
Reach 9R: Basin #1C Discharge
18.0"  Round Pipe   n=0.020   L=27.0'   S=0.0370 '/'   Capacity=13.14 cfs   Outflow=0.00 cfs  0.000 af
Peak Elev=309.19'  Storage=2,681 cf   Inflow=0.10 cfs  0.062 af
Pond 2P: Detention Basin #1C
   Outflow=0.00 cfs  0.000 af
Peak Elev=362.38'  Storage=4,402 cf   Inflow=0.18 cfs  0.101 af
Pond 4P: Detention Basin #1A
   Outflow=0.00 cfs  0.000 af
Peak Elev=326.68'  Storage=2,580 cf   Inflow=0.11 cfs  0.059 af
Pond 6P: Detention Basin #1B
   Outflow=0.00 cfs  0.000 af
Total Runoff Area = 5.492 ac   Runoff Volume = 0.222 af   Average Runoff Depth = 0.48"
98.98% Pervious = 5.436 ac     1.02% Impervious = 0.056 ac

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 18
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 1S: Drainage Area #1C
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.105
0.1
0.095
0.09
0.085
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Type III 24-hr
2-yr Rainfall=3.40"
Runoff Area=84,877 sf
Runoff Volume=0.062 af
Runoff Depth=0.38"
Flow Length=621'
Tc=257.8 min
CN=57
0.10 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 19
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 3S: Drainage Area #1A
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.19
0.18
0.17
0.16
0.15
0.14
0.13
0.12
0.11
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Type III 24-hr
2-yr Rainfall=3.40"
Runoff Area=99,965 sf
Runoff Volume=0.101 af
Runoff Depth=0.53"
Flow Length=424'
Tc=234.9 min
CN=61
0.18 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 20
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 5S: Drainage Area #1B
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.12
0.115
0.11
0.105
0.1
0.095
0.09
0.085
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Type III 24-hr
2-yr Rainfall=3.40"
Runoff Area=54,385 sf
Runoff Volume=0.059 af
Runoff Depth=0.57"
Flow Length=509'
Tc=219.2 min
CN=62
0.11 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 21
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 7R: Basin #1A Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
1
0
Inflow Area=2.295 ac
Avg. Flow Depth=0.00'
Max Vel=0.00 fps
18.0"
Round Pipe
n=0.020
L=111.0'
S=0.0090 '/'
Capacity=6.48 cfs
0.00 cfs
0.00 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 22
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 8R: Basin #1B Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
1
0
Inflow Area=1.249 ac
Avg. Flow Depth=0.00'
Max Vel=0.00 fps
18.0"
Round Pipe
n=0.020
L=28.0'
S=0.0357 '/'
Capacity=12.90 cfs
0.00 cfs
0.00 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 23
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 9R: Basin #1C Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
1
0
Inflow Area=1.949 ac
Avg. Flow Depth=0.00'
Max Vel=0.00 fps
18.0"
Round Pipe
n=0.020
L=27.0'
S=0.0370 '/'
Capacity=13.14 cfs
0.00 cfs
0.00 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 24
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 2P: Detention Basin #1C
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.105
0.1
0.095
0.09
0.085
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Inflow Area=1.949 ac
Peak Elev=309.19'
Storage=2,681 cf
0.10 cfs
0.00 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 25
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 4P: Detention Basin #1A
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.19
0.18
0.17
0.16
0.15
0.14
0.13
0.12
0.11
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Inflow Area=2.295 ac
Peak Elev=362.38'
Storage=4,402 cf
0.18 cfs
0.00 cfs

Type III 24-hr  2-yr Rainfall=3.40"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 26
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 6P: Detention Basin #1B
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.12
0.115
0.11
0.105
0.1
0.095
0.09
0.085
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Inflow Area=1.249 ac
Peak Elev=326.68'
Storage=2,580 cf
0.11 cfs
0.00 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 27
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Time span=0.00-48.00 hrs, dt=0.01 hrs, 4801 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method  -  Pond routing by Stor-Ind method
Runoff Area=84,877 sf   0.00% Impervious   Runoff Depth=1.10"
Subcatchment 1S: Drainage Area #1C
   Flow Length=621'   Tc=257.8 min   CN=57   Runoff=0.32 cfs  0.179 af
Runoff Area=99,965 sf   2.45% Impervious   Runoff Depth=1.37"
Subcatchment 3S: Drainage Area #1A
   Flow Length=424'   Tc=234.9 min   CN=61   Runoff=0.52 cfs  0.262 af
Runoff Area=54,385 sf   0.00% Impervious   Runoff Depth=1.44"
Subcatchment 5S: Drainage Area #1B
   Flow Length=509'   Tc=219.2 min   CN=62   Runoff=0.31 cfs  0.150 af
Avg. Flow Depth=0.00'   Max Vel=0.00 fps   Inflow=0.00 cfs  0.000 af
Reach 7R: Basin #1A Discharge
18.0"  Round Pipe   n=0.020   L=111.0'   S=0.0090 '/'   Capacity=6.48 cfs   Outflow=0.00 cfs  0.000 af
Avg. Flow Depth=0.00'   Max Vel=0.00 fps   Inflow=0.00 cfs  0.000 af
Reach 8R: Basin #1B Discharge
18.0"  Round Pipe   n=0.020   L=28.0'   S=0.0357 '/'   Capacity=12.90 cfs   Outflow=0.00 cfs  0.000 af
Avg. Flow Depth=0.10'   Max Vel=2.26 fps   Inflow=0.11 cfs  0.039 af
Reach 9R: Basin #1C Discharge
18.0"  Round Pipe   n=0.020   L=27.0'   S=0.0370 '/'   Capacity=13.14 cfs   Outflow=0.11 cfs  0.039 af
Peak Elev=312.00'  Storage=6,120 cf   Inflow=0.32 cfs  0.179 af
Pond 2P: Detention Basin #1C
   Outflow=0.11 cfs  0.039 af
Peak Elev=365.27'  Storage=11,405 cf   Inflow=0.52 cfs  0.262 af
Pond 4P: Detention Basin #1A
   Outflow=0.00 cfs  0.000 af
Peak Elev=329.61'  Storage=6,519 cf   Inflow=0.31 cfs  0.150 af
Pond 6P: Detention Basin #1B
   Outflow=0.00 cfs  0.000 af
Total Runoff Area = 5.492 ac   Runoff Volume = 0.591 af   Average Runoff Depth = 1.29"
98.98% Pervious = 5.436 ac     1.02% Impervious = 0.056 ac

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 28
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 1S: Drainage Area #1C
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.34
0.32
0.3
0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Type III 24-hr
10-yr Rainfall=5.00"
Runoff Area=84,877 sf
Runoff Volume=0.179 af
Runoff Depth=1.10"
Flow Length=621'
Tc=257.8 min
CN=57
0.32 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 29
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 3S: Drainage Area #1A
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.55
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Type III 24-hr
10-yr Rainfall=5.00"
Runoff Area=99,965 sf
Runoff Volume=0.262 af
Runoff Depth=1.37"
Flow Length=424'
Tc=234.9 min
CN=61
0.52 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 30
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 5S: Drainage Area #1B
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.34
0.32
0.3
0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Type III 24-hr
10-yr Rainfall=5.00"
Runoff Area=54,385 sf
Runoff Volume=0.150 af
Runoff Depth=1.44"
Flow Length=509'
Tc=219.2 min
CN=62
0.31 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 31
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 7R: Basin #1A Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
1
0
Inflow Area=2.295 ac
Avg. Flow Depth=0.00'
Max Vel=0.00 fps
18.0"
Round Pipe
n=0.020
L=111.0'
S=0.0090 '/'
Capacity=6.48 cfs
0.00 cfs
0.00 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 32
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 8R: Basin #1B Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
1
0
Inflow Area=1.249 ac
Avg. Flow Depth=0.00'
Max Vel=0.00 fps
18.0"
Round Pipe
n=0.020
L=28.0'
S=0.0357 '/'
Capacity=12.90 cfs
0.00 cfs
0.00 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 33
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 9R: Basin #1C Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.12
0.115
0.11
0.105
0.1
0.095
0.09
0.085
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Inflow Area=1.949 ac
Avg. Flow Depth=0.10'
Max Vel=2.26 fps
18.0"
Round Pipe
n=0.020
L=27.0'
S=0.0370 '/'
Capacity=13.14 cfs
0.11 cfs
0.11 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 34
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 2P: Detention Basin #1C
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.34
0.32
0.3
0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Inflow Area=1.949 ac
Peak Elev=312.00'
Storage=6,120 cf
0.32 cfs
0.11 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 35
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 4P: Detention Basin #1A
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.55
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Inflow Area=2.295 ac
Peak Elev=365.27'
Storage=11,405 cf
0.52 cfs
0.00 cfs

Type III 24-hr  10-yr Rainfall=5.00"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 36
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 6P: Detention Basin #1B
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.34
0.32
0.3
0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Inflow Area=1.249 ac
Peak Elev=329.61'
Storage=6,519 cf
0.31 cfs
0.00 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 37
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Time span=0.00-48.00 hrs, dt=0.01 hrs, 4801 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method  -  Pond routing by Stor-Ind method
Runoff Area=84,877 sf   0.00% Impervious   Runoff Depth=1.50"
Subcatchment 1S: Drainage Area #1C
   Flow Length=621'   Tc=257.8 min   CN=57   Runoff=0.45 cfs  0.243 af
Runoff Area=99,965 sf   2.45% Impervious   Runoff Depth=1.81"
Subcatchment 3S: Drainage Area #1A
   Flow Length=424'   Tc=234.9 min   CN=61   Runoff=0.70 cfs  0.346 af
Runoff Area=54,385 sf   0.00% Impervious   Runoff Depth=1.89"
Subcatchment 5S: Drainage Area #1B
   Flow Length=509'   Tc=219.2 min   CN=62   Runoff=0.42 cfs  0.196 af
Avg. Flow Depth=0.14'   Max Vel=1.43 fps   Inflow=0.13 cfs  0.036 af
Reach 7R: Basin #1A Discharge
18.0"  Round Pipe   n=0.020   L=111.0'   S=0.0090 '/'   Capacity=6.48 cfs   Outflow=0.12 cfs  0.036 af
Avg. Flow Depth=0.09'   Max Vel=2.13 fps   Inflow=0.09 cfs  0.033 af
Reach 8R: Basin #1B Discharge
18.0"  Round Pipe   n=0.020   L=28.0'   S=0.0357 '/'   Capacity=12.90 cfs   Outflow=0.09 cfs  0.033 af
Avg. Flow Depth=0.15'   Max Vel=3.02 fps   Inflow=0.29 cfs  0.103 af
Reach 9R: Basin #1C Discharge
18.0"  Round Pipe   n=0.020   L=27.0'   S=0.0370 '/'   Capacity=13.14 cfs   Outflow=0.29 cfs  0.103 af
Peak Elev=312.00'  Storage=6,120 cf   Inflow=0.45 cfs  0.243 af
Pond 2P: Detention Basin #1C
   Outflow=0.29 cfs  0.103 af
Peak Elev=366.00'  Storage=13,488 cf   Inflow=0.70 cfs  0.346 af
Pond 4P: Detention Basin #1A
   Outflow=0.13 cfs  0.036 af
Peak Elev=330.00'  Storage=7,140 cf   Inflow=0.42 cfs  0.196 af
Pond 6P: Detention Basin #1B
   Outflow=0.09 cfs  0.033 af
Total Runoff Area = 5.492 ac   Runoff Volume = 0.785 af   Average Runoff Depth = 1.72"
98.98% Pervious = 5.436 ac     1.02% Impervious = 0.056 ac

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 38
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 1S: Drainage Area #1C
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.48
0.46
0.44
0.42
0.4
0.38
0.36
0.34
0.32
0.3
0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Type III 24-hr
25-yr Rainfall=5.70"
Runoff Area=84,877 sf
Runoff Volume=0.243 af
Runoff Depth=1.50"
Flow Length=621'
Tc=257.8 min
CN=57
0.45 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 39
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 3S: Drainage Area #1A
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.75
0.7
0.65
0.6
0.55
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Type III 24-hr
25-yr Rainfall=5.70"
Runoff Area=99,965 sf
Runoff Volume=0.346 af
Runoff Depth=1.81"
Flow Length=424'
Tc=234.9 min
CN=61
0.70 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 40
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Subcatchment 5S: Drainage Area #1B
Runoff
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.46
0.44
0.42
0.4
0.38
0.36
0.34
0.32
0.3
0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Type III 24-hr
25-yr Rainfall=5.70"
Runoff Area=54,385 sf
Runoff Volume=0.196 af
Runoff Depth=1.89"
Flow Length=509'
Tc=219.2 min
CN=62
0.42 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 41
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 7R: Basin #1A Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.14
0.13
0.12
0.11
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Inflow Area=2.295 ac
Avg. Flow Depth=0.14'
Max Vel=1.43 fps
18.0"
Round Pipe
n=0.020
L=111.0'
S=0.0090 '/'
Capacity=6.48 cfs
0.13 cfs
0.12 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 42
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 8R: Basin #1B Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.105
0.1
0.095
0.09
0.085
0.08
0.075
0.07
0.065
0.06
0.055
0.05
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
Inflow Area=1.249 ac
Avg. Flow Depth=0.09'
Max Vel=2.13 fps
18.0"
Round Pipe
n=0.020
L=28.0'
S=0.0357 '/'
Capacity=12.90 cfs
0.09 cfs
0.09 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 43
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Reach 9R: Basin #1C Discharge
Inflow
Outflow
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.32
0.3
0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Inflow Area=1.949 ac
Avg. Flow Depth=0.15'
Max Vel=3.02 fps
18.0"
Round Pipe
n=0.020
L=27.0'
S=0.0370 '/'
Capacity=13.14 cfs
0.29 cfs
0.29 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 44
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 2P: Detention Basin #1C
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.48
0.46
0.44
0.42
0.4
0.38
0.36
0.34
0.32
0.3
0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Inflow Area=1.949 ac
Peak Elev=312.00'
Storage=6,120 cf
0.45 cfs
0.29 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 45
HydroCAD® 10.20-5c  s/n 11668  © 2023 HydroCAD Software Solutions LLC
Pond 4P: Detention Basin #1A
Inflow
Primary
Hydrograph
Time  (hours)
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Flow  (cfs)
0.75
0.7
0.65
0.6
0.55
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Inflow Area=2.295 ac
Peak Elev=366.00'
Storage=13,488 cf
0.70 cfs
0.13 cfs

Type III 24-hr  25-yr Rainfall=5.70"
Butlertown Road.Proposed Conditions.11.23.2024
  Printed  12/19/2024
Prepared by DLC Engineering Services, LLC
Page 46
HydroCAD® 10.20-5c  s/n 11668  © 20