HomeMy WebLinkAboutPD 2020-0049; HOPE ELEMENTARY SCHOOL; DRAINAGE STUDY; 2022-08-01DRAINAGE STUDY
HOPE ELEMENTARY SCHOOL (ES)
3010 Tamarack Avenue
Carlsbad, CA 92010
PD2020‐0049
GR 2020‐0035
DWG 528‐2A
Design Review Number: 4
August 1, 2022
Prepared for
6225 El Camino Real
Carlsbad, California 92009
(760)331‐5000
Prepared by
30 Corporate Park, Suite 401
Irvine, CA 92606
(949)252‐1688
Prepared by: Joseph Litchfield, P.E.
Under the Supervision of: Alan Wing‐Chi Lee, P.E.
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Contents
Executive Summary ....................................................................................................................................... 3
I. Project Description................................................................................................................................ 3
Introduction .............................................................................................................................................. 3
Existing Condition ..................................................................................................................................... 4
Proposed Condition .................................................................................................................................. 6
Design Criteria and Methods .................................................................................................................... 8
II. Hydrology Analysis ................................................................................................................................ 8
Rational Method Peak Flow ...................................................................................................................... 8
Modified Rational Method for Routing of Peak Flows ........................................................................... 11
III. Hydraulic Analysis of Site Piping ..................................................................................................... 12
Pipe Flows ............................................................................................................................................... 12
IV. Stormwater Quality Management Plan (SWQMP) ......................................................................... 13
V. Conclusion ........................................................................................................................................... 13
Appendix A – Vicinity Map .......................................................................................................................... 14
Appendix B – Soils Map ............................................................................................................................... 15
Appendix C – Isopluvial Map, 100‐Year Rainfall Event ‐ 6 Hours ................................................................ 16
Appendix D – Isopluvial Map, 100‐Year Rainfall Event – 24 hours ............................................................. 17
Appendix E – Intensity Duration Curve ....................................................................................................... 18
Appendix F – Rational Method Calculations – Pre‐Construction ................................................................ 19
Appendix G – Rational Method Calculations – Post‐Construction and Modified Rational Method Routing
Calculations for POC #1 ............................................................................................................................... 20
Appendix H – Hydrology Map – Pre‐Construction ...................................................................................... 21
Appendix I – Hydrology Map – Post Construction ...................................................................................... 22
Appendix J – TRWE Detention Analysis at POC 2 ........................................................................................ 23
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Executive Summary
This report discusses the existing and proposed drainage for the project area at 3010 Tamarack Avenue
due to the new Classroom Building / Modernization project at Hope Elementary School (ES). The
hydrology is calculated using the Rational Method to determine the peak flows generated from the site
during a 100‐year, 6‐hour storm event for both the pre‐development and post‐project conditions and is
based on the process outlined in the San Diego County Hydrology Manual. Hydrographs and routing of
the drainage areas are also developed based on the SDCHM at specific Points of Compliance (POCs).
The drainage of the site is modified to account for the water quality requirements and available areas to
incorporate Best Management Practices (BMPs) as a part of the Storm Water Quality Management Plan
(SWQMP) “Hope Elementary School New Classroom Building / Modernization PD2020‐0049” by FPL &
Associates dated 8‐1‐2022. The net difference in increased peak volumes of discharge from the site are
mitigated through a combination of tree wells and landscaped biofiltration / partial retention ponds.
Due to site constraints and proposed reconfiguration of the drainage patterns on site to mitigate water
quality and hydromodification, drainage from the project site is affected at runoff locations: the north
(POC #2), south (POC#1), east and west (the east and west are not identified as official POCs as the
disturbed area of the project does not outflow to the east or west). Unmitigated peak flows at both POC
#1 and POC #2 increase as a result of the proposed project, but the incorporation of the treatment
ponds and tree wells mitigates the outflow to pre‐project conditions for the 100‐year, 6‐hour storm
event.
All calculations, maps and charts utilized in the process are included in the Appendix for reference.
I. Project Description
Introduction
This report summarizes the hydrology and hydraulic calculations for the 100‐year storm for the New
Classroom Building / Modernization at Hope Elementary School, Carlsbad Unified School District, 3010
Tamarack Avenue, Carlsbad, California, 92010. The modernization is taking place at an existing
elementary school that is approximately 7.5 acres developed on a 13.2 acre parcel of land.
Figure 1 ‐ Hope Elementary School Aerial Image (Google Maps, 2020). North is to the right.
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Figure 2 ‐ Sheet G201 from Division of State Architect (DSA) Approved Set of Drawings ‐ Existing vs. New Construction on Site
This report will focus on the hydrology and hydraulic calculations for the Project Area to be in
conformance with the City of Carlsbad submittal requirements.
Existing Condition
The project area is located at 3010 Tamarack Avenue in Carlsbad, California, approximately one‐half mile
south of Highway 78, and approximately three miles east from the Pacific Ocean. The developed portion
of the site is at the higher elevations adjacent to Tamarack Avenue, with sloped boundaries to the north,
west, and south. The existing site is overlain with existing school buildings, asphalt and concrete
surfaces for parking and play areas, and grass / lawn areas. There is a significant undeveloped portion of
the property that is generally open, natural space that also includes the natural drainage channels to the
north, west, and south.
The existing drainage pattern of the developed site has outflow runoff from six different areas as
follows:
1. The south side of the developed portion of the parcel collects drainage on the surface via sheet
flow to an existing curb and gutter that spans the south end of the active campus area. The
drainage is then collected to an existing shallow catch basin and parkway drain that discharges
onto Tamarack Avenue. [Outflow #1]
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2. The southern portion of the driveway / parking area discharges to the east directly onto
Tamarack Avenue. [Outflow #2]
3. The northern portion of the driveway / parking area discharges to the east directly onto
Tamarack Avenue. [Outflow #3]
4. A small portion of the existing site, the parkway between the public sidewalk and the parking lot
and also between the two lot entrances, discharges to the east directly onto Tamarack Avenue
via sheet flow across the public sidewalk. [Outflow #4]
5. The central / west portion of the site, which comprises the primary building pad area, collects
drainage runoff through multiple drain inlets, pipes, and surface swales and diverts the drainage
to the west side of the property, where a steep 18” diameter reinforced concrete pipe (RCP)
storm drain (18” RCP) directs drainage to a lower portion of the canyon and outlets to a grouted
rip rap to control erosion. [Outflow #5]
6. The north end of the property sheet flows across an existing grass / lawn area (multi‐purpose
field) that is collected via an existing concrete curb and gutter at the north end of the field to
channel the runoff to an existing catch basin and 18” RCP storm drain that outlets near the
bottom of the canyon on a grouted rip rap surface to control erosion. An additional bench drain
is located on the northern portion of the parcel that collects runoff from the northern slope and
directs that drainage to a down drain that terminates at a similar elevation in the canyon to the
north. [Outflow #6]
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Figure 3 ‐ As Built Civil Engineering Drawing for Grading and Drainage – dated 1986 – Calavera Hills Elementary School (now
Hope Elementary School)
Proposed Condition
The project area will be developed with additional permanent buildings within the central building pad
area, remove some of the existing portable buildings along the western perimeter, and extend the
asphalt play area to the north. The grade of the overall site will not vary significantly from existing, with
the lone exception of the northern play surface extension creating a small, sloped area in order to
maintain fairly level grades in the hardscape area.
The boundaries of the drainage areas are modified in such a way as to divert the newly disturbed areas
to locations on the north and south that are able to accommodate appropriate BMPs for water quality
and hydromodification requirements of the SWQMP. Specifically, grading and drainage of the newly
disturbed portions specifically route stormwater to the north and south, changing the current drainage
fairly significantly. As an example, the current peak drainage to the west (100‐year flow) is 20.84 cubic
feet per second (cfs), but after construction will reduce to 9.64 cfs, a 54% reduction of the peak flow.
The balance of that flow is diverted to the east and north to the new BMPs. Note that all drainage that
will flow to the west is from undisturbed areas, and therefore requires no treatment or
hydromodification.
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The central area, which is the majority of the disturbed area for this project, is divided into two distinct
Drainage Management Areas (DMAs) for the purpose of proper treatment and filtration prior to
discharge from the site. One area will be collected via catch basins and drain piping that will be filtered
through a landscaped partial retention / biofiltration pond to the east and north, and will outflow to the
north. As part of the partial retention / biofiltration hydromodification design, the low flows are
controlled via the smaller pipe / orifice from the underdrain of the ponds. Larger flows will be picked up
within the treatment pond overflow structure (catch basin with outlet pipe) sufficient to carry the 100‐
year flow to the outlet at the north end of the multi‐use field. The current outlet is an existing catch
basin and down drain as described in the existing condition above. A detailed analysis of this flow is
included in this report.
The second central area is primarily the new asphalt surface of the play area, and is designed to sheet
flow to the east to be collected into the same partial retention / biofiltration pond and is designed in the
same manner as the first central area for sizing of the pond, hydromodification, and outlet to the north.
This is POC #2.
Due to the grades and slopes of the drainage areas, as well as the restriction of placement of the ponds
both from a geotechnical perspective and client direction to preserve area for multi‐use play fields, the
pond is lower in grade by approximately five feet in order to properly receive the outlet flow of the
disturbed areas at the surface of the pond and properly be treated through the mulch, landscaping,
filtration media, and gravel of the ponds.
A large portion of the south area will be diverted to new tree wells that will serve as both water quality
and hydromodification BMPs. Water is collected via sheet flow from the new improved areas along the
southern border of the existing campus within the existing curb and gutter. Flow is diverted east along
the curb and gutter to new tree wells via the removal of the gutter portion of the C&G and re‐grading
the area to ensure the tree wells behave in a sump condition to catch all flows for the areas upstream.
Overflow will be captured via a catch basin and outlet pipe to the south that continues outside of the
existing campus fence and down to the nearest catch basin on Tamarack Avenue, coring into the back of
the basin to ensure the existing drainage pattern remains close to the same so that erosion potential at
new locations is not a factor.
A smaller portion of the south area will be picked up via a concrete and earthen (grass‐lined) swale that
parallels the back of the existing sidewalk and security fence of the school’s parking lot, directing the
remaining drainage of the disturbed areas to the south. The previous outlet drain was a shallow catch
basin inlet and parkway drain that carried flow to Tamarack Avenue. This device will be bypassed by
installing a solid cover on the existing drain and removing the curb at the back of the device to allow the
drain water to flow to a new partial retention / biofiltration pond just outside of the existing campus
fence. The pond will be sized to handle the water quality controls required of the drainage management
area (DMA) and overflow is via a catch basin and pipe that ties together with the same overflow from
the tree wells serving the south area of campus, exiting at the same catch basin on Tamarack Avenue.
This forms POC #1.
Small portions of the west side of campus that are being disturbed drain along the east side of campus
along an existing curb towards the north and ultimately the same outlet as the central / east areas
described above. Although the disturbed areas mostly remove impervious areas as a part of the project
(primarily old relocatable school buildings), there are some impervious areas that do not allow the area
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to be strictly self‐mitigating. Additional tree wells, graded such that it becomes a sump condition along
the western border of campus that collects all the surface drainage for that area, are used to treat and
serve as hydromodification for that area. An overflow of a catch basin and pipe carries the larger 100‐
year flows to the existing drainage outlet / catch basin to the north. This is the same outlet of campus
as the east / central basin is draining towards (POC #2).
The existing multi‐use field that is undisturbed is considered self‐mitigating and does not require
treatment or hydromodification control. The area sheet flows to the north and is collected by a curb
and gutter along the boundaries of campus, discharging at the same location as the existing condition at
the catch basin to the north.
Due to the modified drainage flowing to natural drainage courses to the north and south of the project
area (POCs #1 and #2), hydromodification is incorporated into the proposed BMPs to mitigate runoff to
mirror pre‐development conditions. The sizing of the proposed partial‐retention and biofiltration is such
that the hydromodification volume and low‐flow orifice is part of the proposed BMP design control
volume and overflow design. A separate hydromodification analysis is part of the project SWQMP. This
drainage report further analyzes the 100‐year, 6‐hour flow routing through POC #1 and POC #2 to
confirm the flows do not exceed pre‐development conditions.
Design Criteria and Methods
The hydrology was calculated as a peak flow using the Rational Method and process provided in the San
Diego County Hydrology Manual. The methodology included:
a determination of a time of concentration for each subarea utilizing the methodology provided
in Section 3.1.4.1 of the Hydrology Manual; variable Tc (minutes)
determining the rainfall intensity using the methodology in Section 3.1.3 of the Hydrology
Manual; variable I (inches / hour)
Determine the Area of the subarea in question; variable A (acres)
Using the impervious and pervious coverage areas to determine the runoff coefficient C per the
methodology in 3.1.2 in the Hydrology Manual. Criteria for this project site is Soil Type D;
variable C (unitless)
Using the variables found, calculate the proposed runoff Q in cubic feet per second (cfs). Q=CIA
This process was done for both the pre‐construction (existing) and post‐construction (proposed)
condition in order to compare the total runoff for both conditions. The results are shown in Appendix E
& F, respectively.
Use of computer software included AutoCAD for geometry and areas of the project site and Microsoft
Excel for calculations of the Rational Method formula.
II. Hydrology Analysis
Rational Method Peak Flow
See Appendices E & F for calculations used to determine the Rational Method variables and final runoff
(Q) values in cubic feet per second (cfs) for each drainage sub area.
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The subareas were combined to determine the total peak flow draining from the site. This was strictly
an arithmetic sum of the peak flows, and is a conservative estimate by not taking into account routing of
the flows for different times of concentration and routing of the hydrographs to determine a modified
peak outflow. This was done to identify areas that would require mitigation and further analysis and
design. The following is a description of each of the discharge locations from the site.
Table 1 – Pre-Construction Runoff Description
Outflow
# Sub Areas Group Area
Flows Description
(No.) (No.) (cfs)
1 A + H 2.18
(1.87)*
South drainage to existing drain basin; exits via parkway
culvert onto Tamarack Avenue. Point of Compliance #1
(POC #1)
2 B 1.41 Southern driveway (Exit Driveway) - drains directly to
Tamarack Avenue
3 D 2.07 Northern driveway (Entrance Driveway) - drains directly
to Tamarack Avenue
4 E 0.13 Small edge behind sidewalk adjacent to Tamarack Avenue
- drains directly to Tamarack Avenue
5 C, F, G, I, J,
K, L, M, N, O 20.84
Central drainage area that drains to the west to 18" RCP
and down slope to existing energy dissipator and
drainage ditch. Most of the runoff is collected via area
drains and site piping.
6 P 4.18
(6.4)*
North drainage to existing catch basin and 18" RCP down
drain to existing energy dissipator and drainage ditch.
Point of Compliance #2 (POC #2)
Note: two values are included for Outflow #1 in Table 1 and Outflow #6 in Tables 1 and 2. The first
number is the arithmetic sum of the 100-year flows from each collection of subareas at the indicated
outflow. The second number for Outflow #1 is the result of hydrograph routing at POC #1 and reflects an
offset of time for the hydrograph from Subarea H to route to POC #1. The second number for Outflow #6
is the output from the SWMM model performed for POC #2 and is included as Appendix J. Additional
discussion is included in the following sections.
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Table 2 – Post-Construction Runoff Description
Outflow # Sub Areas
Group
Area
Flows Description
(No.) (No.) (cfs)
1 A + H (POC #1) 1.93
South drainage to tree wells and treatment pond. Combines
into one outlet pipe to back of catch basin on Tamarack Ave.
Point of Compliance #1 (POC #1)
2 B 1.35 Southern driveway (Exit Driveway) - drains directly to
Tamarack Avenue
3 D 1.81 Northern driveway (Entrance Driveway) - drains directly to
Tamarack Avenue
4 E 0.13 Small edge behind sidewalk adjacent to Tamarack Avenue -
drains directly to Tamarack Avenue
5 F, I, J, K, L, M 9.64 Central drainage area that drains to the west to 18" RCP and
down slope to existing energy dissipator and drainage ditch.
6 C, G, N, O, P,
Q (POC #2)
16.56
(19.2)*
New paved areas of campus including diverted parking lot and
multi-use field that drains to existing catch basin and 18" RCP
down drain at north edge of campus. Point of Compliance #2
(POC #2)
Table 3 – Summary of Peak Flow Results.
Outflow #
Q100 Pre-
Construction
(Existing)
Q100 Post-Construction
(Proposed)
Q100 Post-Construction
(Proposed Mitigated)
(No.) (cfs) (cfs) (cfs)
1 (POC #1) 1.87 1.93 0.67
2 1.41 1.35 1.35
3 2.07 1.81 1.81
4 0.13 0.13 0.13
5 20.84 9.64 9.64
6 (POC #2) 6.4 19.20 5.40
It was identified during this analysis that the peak flows from Outflow #1 and Outflow #6 were greater
than the pre-project condition, and therefore warranted further analysis and design to mitigate the peak
flows at these points of compliance (POCs). Outflows 2-5 are derived from areas that are not disturbed
on the project site and either see no change in outflow, or saw a reduction due to areas picked up by
POC #2.
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In both POC cases, biofiltration with partial retention treatment ponds are incorporated into the storm
water quality designs, therefore routing of the flow through the ponds is analyzed and utilized to
confirm the size of the ponds to mitigate the 100-year, 6-hour peak discharge to below pre-project
levels.
Modified Rational Method for Routing of Peak Flows
The mitigation of flows at POC #1 and POC #2 is done by routing the flows through the prescribed
treatment ponds and tree wells prescribed by the project SWQMP. Although the ponds are initially
sized to handle water quality treatment of the design storm, as well as hydromodification of lower
flows, the outflows are further analyzed to ensure the 100-year, 6-hour outflow is mitigated to pre-
project conditions.
At POC #1, hydrographs were developed for SubArea A and H to determine the actual time and routing
of the peak flow. The results were then tabulated and analyzed through a level-pool routing scenario to
account for the available storage and outflows from the treatment ponds and tree wells, including their
overflow and drain structures. See Appendix G for tabulation of hydrograph data.
At POC #2, the mitigation of the peak flows is analyzed in detail as a separate analysis utilizing the
SWMM Model. See Appendix J for the full analysis.
0.00
0.50
1.00
1.50
2.00
2.50
0 50 100 150 200 250 300 350 400
Cu
b
i
c
F
e
e
t
P
e
r
S
e
c
o
n
d
Time (minutes)
Outlet Flow from POC #1
Combo A+H Pre-Development Combo A+ H Post-Development Total Mitigated Outflow POC #1
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III. Hydraulic Analysis of Site Piping
Pipe Flows
The design requirement for the campus is to effectively convey the 100-year return flows safely off of
the property. The hydrology that defined the peak flows are described in the previous section. This
section shows the sizing of piping conduit to properly convey the flows to ensure proper conveyance on
and off the project area.
Hydraulic capacity is calculated using Manning’s Equation. The calculation is applied to the pipe
conduits provided and the design was adjusted via conduit size or slope to properly convey the 100-year
peak flows. Manning’s equation is as follows:
Q = (1.49/n) * A * R * (2/3 * S ^ 1.2)
where
Q = capacity of the conduit in cubic feet per second
n = Manning’s roughness coefficient (for plastic pipe 0.010 is used)
A = cross sectional area of the conduit or pipe
R = the ratio of cross-sectional area (A) to the wetted perimeter of the conduit or pipe (P)
P = wetted perimeter, or for a pipe flowing full would equal the full perimeter of the pipe
S = slope of the conduit or pipe in feet / foot
The following table summarizes the calculation results using Manning’s equation at key points
throughout the project and is shown on the post-construction hydrology map in Appendix I.
Sub Area
Q demand
(100-year, 6-
hour)
HPDE
Pipe
Diameter
Provided
Slope Q
capacity
Q capacity >
Q demand?
(No.) (cfs) (in) (ft/ft) (cfs)
Internal Piping on Project
C, G, N 7.48 18 0.010 13.69 OK
C, G, N, O 6.10 (routed)* 18 0.011 14.36 OK
Q 0.96 8 0.010 1.58 OK
Outflow Piping Discharge Off Project Area
A + H 0.67 (routed)* 8 0.015 1.93 OK
C, G, N, O, P,
Q 19.20 18 0.380 84.41 OK
*Outflow peak reduced due to flow routing at treatment pond.
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IV. Stormwater Quality Management Plan (SWQMP)
As required by the City of Carlsbad to be in conformance with the Regional Water Quality Control Board
permit requirements, a separate SWQMP is provided to describe the Best Management Practices
(BMPs) to both treat and retain stormwater on the site to the maximum extent practical, as well as a
discussion on hydromodification as it relates to mitigating outflow from the site to protect surrounding
natural drainage systems.
V. Conclusion
The proposed drainage devices properly conveys the proposed 100‐year flows from the project site at
each Outflow location. The incorporation of treatment ponds and tree wells with overflow weirs allows
for level‐pool routing of the se peak flows, mitigating the total flows to within pre‐project conditions.
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Appendix A – Vicinity Map
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Appendix B – Soils Map
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Appendix C – Isopluvial Map, 100‐Year Rainfall Event ‐ 6 Hours
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Appendix D – Isopluvial Map, 100‐Year Rainfall Event – 24 hours
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Appendix E – Intensity Duration Curve
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Appendix F – Rational Method Calculations – Pre‐Construction
Appendix F
PRE‐CONSTRUCTION HYDROLOGY CALCULATIONS
100‐year storm event/ return period
Hope ES ‐ 3010 Tamarack Avenue
References to Appendices or Tables are from the San Diego County Hydrology Manual
Rational Method
Soil Type D (Appendix A ‐ 33deg10'N, 117deg18'W)
P6 2.8 (Appendix B ‐ 33deg10'N, 117deg18'W)
P24 5.1 (Appendix B ‐ 33deg10'N, 117deg18'W)
*P6 is within 45%‐65% of P24, acceptable per section 3.1.3
Cp 0.35 Table 3‐1 for 0% impervious, soil type D
Sub Area Total Area Area Pervious Area
Impervious Total Area Area Pervious Area
Impervious
Overland Flow
Length Slope
(No.) (ft^2) (ft^2) (ft^2) (acre) (acre) (acre) (ft) (%)
A 20,808.03 8,415.40 12,392.63 0.48 0.19 0.28 204.59 2.42
B 10,110.92 1,201.11 8,909.81 0.23 0.03 0.20 180.95 2.46
C 20,048.65 407.00 19,641.65 0.46 0.01 0.45 279.41 0.70
D 15,890.09 3,455.13 12,434.96 0.36 0.08 0.29 187.03 6.80
E 2,024.96 2,024.96 ‐ 0.05 0.05 ‐ 9.60 17.22
F 9,480.55 606.19 8,874.36 0.22 0.01 0.20 88.54 0.83
G 16,515.61 1,197.29 15,318.32 0.38 0.03 0.35 155.02 0.59
H 3,098.60 558.18 2,540.42 0.07 0.01 0.06 52.15 3.67
I 12,650.47 1,201.00 11,449.47 0.29 0.03 0.26 169.25 0.55
J 22,434.94 1,104.79 21,330.15 0.52 0.03 0.49 114.80 0.91
K 16,519.19 1,225.75 15,293.44 0.38 0.03 0.35 169.66 0.81
L 4,613.15 4,268.55 344.60 0.11 0.10 0.01 57.67 2.28
M 5,709.65 ‐ 5,709.65 0.13 ‐ 0.13 144.97 0.64
N 2,923.78 ‐ 2,923.78 0.07 ‐ 0.07 230.49 1.37
O 43,685.08 1,354.30 42,330.78 1.00 0.03 0.97 253.19 2.70
P 123,419.72 95,629.82 27,789.90 2.83 2.20 0.64 388.68 1.46
Sec 3.1.2 Sec 3.1.4.1 Sec 3.1.3
Sub Area Area Ai Ap Weighted C Time of
Concentration
Rainfall
Intensity Q100 Runoff
(No.) (acres) (‐)(‐)(‐) (minutes) (in/hour) (cfs)
A 0.48 0.6 0.4 0.68 8.05 5.43 1.77
B 0.23 0.88 0.12 0.83 5 7.38 1.41
C 0.46 0.98 0.02 0.89 7.12 5.87 2.40
D 0.36 0.78 0.22 0.78 5 7.38 2.07
E 0.05 0 1 0.35 5 7.38 0.13
F 0.22 0.94 0.06 0.87 5 7.38 1.41
G 0.38 0.93 0.07 0.86 6.41 6.29 2.06
H 0.07 0.82 0.18 0.8 5 7.38 0.41
I 0.29 0.91 0.09 0.85 7.15 5.86 1.44
J 0.52 0.95 0.05 0.87 5 7.38 3.34
K 0.38 0.93 0.07 0.86 6.04 6.53 2.13
L 0.11 0.07 0.93 0.39 7.37 5.74 0.25
M 0.13 1 0 0.9 5.03 7.35 0.86
N 0.07 1 0 0.9 5 7.38 0.46
O 1 0.97 0.03 0.88 5 7.38 6.49
P 2.83 0.23 0.77 0.48 19.39 3.08 4.18
Total Acres:7.6 30.81Total Runoff (cfs) =
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Appendix G – Rational Method Calculations – Post‐Construction and
Modified Rational Method Routing Calculations for POC #1
Appendix G
POST‐CONSTRUCTION HYDROLOGY CALCULATIONS
100‐year storm event/ return period
Hope ES ‐ 3010 Tamarack Avenue
References to Appendices or Tables are from the San Diego County Hydrology Manual
Rational Method
Soil Type D (Appendix A ‐ 33deg10'N, 117deg18'W)
P6 2.8 (Appendix B ‐ 33deg10'N, 117deg18'W)
P24 5.1 (Appendix B ‐ 33deg10'N, 117deg18'W)
*P6 is within 45%‐65% of P24, acceptable per section 3.1.3
Cp 0.35 Table 3‐1 for 0% impervious, soil type D
Sub Area Total Area Area Pervious Area
Impervious Total Area Area Pervious Area
Impervious
Overland Flow
Length Slope
(No.) (ft^2) (ft^2) (ft^2) (acre) (acre) (acre) (ft) (%)
A 8,178.00 5,078.00 3,100.00 0.19 0.12 0.07 204.59 2.60
B 9,592.00 1,201.11 8,390.89 0.22 0.03 0.19 180.95 2.46
C 22,372.00 1,435.00 20,937.00 0.51 0.03 0.48 279.41 0.70
D 15,907.00 5,999.00 9,908.00 0.37 0.14 0.23 187.03 6.80
E 2,024.96 2,024.96 ‐ 0.05 0.05 ‐ 9.60 17.22
F 9,018.00 606.19 8,411.81 0.21 0.01 0.19 88.54 0.83
G 9,013.00 ‐ 9,013.00 0.21 ‐ 0.21 155.02 0.59
H 20,499.00 7,099.00 13,400.00 0.47 0.16 0.31 275.00 1.02
I 16,123.00 2,398.00 13,725.00 0.37 0.06 0.32 169.25 0.55
J 21,696.00 1,777.89 19,918.11 0.50 0.04 0.46 114.80 0.91
K 16,519.19 1,225.75 15,293.44 0.38 0.03 0.35 169.66 0.81
L 7,237.00 4,613.15 2,623.85 0.17 0.11 0.06 57.67 2.28
M 4,944.00 ‐ 4,944.00 0.11 ‐ 0.11 144.97 0.64
N 22,974.00 600.00 22,374.00 0.53 0.01 0.51 253.19 2.70
O 52,609.00 2,100.00 50,509.00 1.21 0.05 1.16 407.67 1.39
P 67,899.00 67,899.00 ‐ 1.56 1.56 ‐ 332.00 1.66
Q 23,328.00 11,669.00 11,659.00 0.54 0.27 0.27 340.00 2.60
Sec 3.1.2 Sec 3.1.4.1 Sec 3.1.3
Sub Area Area Ai Ap Weighted C
Time of
Concentration
(min)
Rainfall
Intensity
(in/hr)
Q100 Runoff
(cfs)
(No.) (acres) (acres) (acres) (‐) (minutes) (in/hour) (cfs)
A 0.19 0.38 0.62 0.56 10.11 4.68 0.50
B 0.22 0.87 0.13 0.83 5 7.38 1.35
C 0.51 0.94 0.06 0.87 7.79 5.54 2.46
D 0.37 0.62 0.38 0.69 5.33 7.08 1.81
E 0.05 0 1 0.35 5 7.38 0.13
F 0.21 0.93 0.07 0.86 5 7.38 1.33
G 0.21 1 0 0.9 5.34 7.07 1.34
H 0.47 0.65 0.35 0.71 11.56 4.3 1.43
I 0.37 0.85 0.15 0.82 8 5.45 1.65
J 0.5 0.92 0.08 0.86 5 7.38 3.17
K 0.38 0.93 0.07 0.86 6.04 6.53 2.13
L 0.17 0.36 0.64 0.55 5.71 6.77 0.63
M 0.11 1 0 0.9 5.03 7.35 0.73
N 0.53 0.97 0.03 0.88 5 7.38 3.44
O 1.21 0.96 0.04 0.88 7.16 5.85 6.23
P 1.56 0 1 0.35 20.77 2.94 1.61
Q 0.54 0.50 0.50 0.63 11.34 4.35 1.48
Total Acres:7.6 31.42Total Runoff (cfs) =
QA QH Qtotal QA QH Qtotal Input Q Output Q Input
Storage
Output
Storage
Cumulati
ve
Storage
Max
Basin
Storage
Below
Overflow
Volume
Above
Overflow
Invert
Outflow Input Output
Input
Storage
Output
Storage
Cumulati
ve
Storage
Max
Basin
Storage
Outflow
(min) (cfs) (cfs) (cfs) (cfs) (cfs) (cfs) (cfs) (cfs) (cf) (cf) (cf) (cf) (cf) (cfs) (cfs) (cfs) (cf) (cf) (cf) (cf) (cfs) (cfs)
0 0.00 0.00 0.00 0 0 0.00 0.00 0 0.00 0.00 0.00
9 0.10 0.00 0.10 000.00 0.00000050300 0.000.000.000.000.001425.00 0.00 0.00
18 0.00 0.00 0.00 000.00 0.00000050300 0.000.000.000.000.001425.00 0.00 0.00
27 0.00 0.00 0.00 000.00 0.00000050300 0.000.000.000.000.001425.00 0.00 0.00
36 0.00 0.00 0.00 000.00 0.00000050300 0.000.000.000.000.001425.00 0.00 0.00
45 0.00 0.00 0.00 000.00 0.00000050300 0.000.000.000.000.001425.00 0.00 0.00
54 0.00 0.00 0.00 000.00 0.00000050300 0.000.000.000.000.001425.00 0.00 0.00
63 0.10 0.00 0.10 000.00 0.00000050300 0.000.000.000.000.001425.00 0.00 0.00
72 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.0054.000.0054.001425.00 0.07 0.07
81 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.0754.0036.6971.311425.00 0.08 0.08
90 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.0854.0043.3581.961425.00 0.09 0.09
99 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.0954.0047.1388.831425.00 0.09 0.09
108 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.0954.0049.4693.371425.00 0.09 0.09
117 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.0954.0050.9696.411425.00 0.10 0.10
126 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.1054.0051.9598.461425.00 0.10 0.10
135 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.1054.0052.6199.851425.00 0.10 0.10
144 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.1054.0053.05100.80 1425.00 0.10 0.10
153 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.1054.0053.36101.44 1425.00 0.10 0.10
162 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.1054.0053.56101.88 1425.00 0.10 0.10
171 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.1054.0053.70102.19 1425.00 0.10 0.10
180 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.1054.0053.79102.39 1425.00 0.10 0.10
189 0.10 0.00 0.10 0 0.1 0.10 0.00000050300 0.100.1054.0053.86102.53 1425.00 0.10 0.10
198 0.10 0.00 0.10 0.1 0.1 0.20 0.10 0 54 0 54 503 0 0 0.10 0.10 54.00 53.90 102.63 1425.00 0.10 0.10
207 0.20 0.00 0.20 0.1 0.1 0.20 0.10 0 54 0 108 503 0 0 0.10 0.10 54.00 53.93 102.69 1425.00 0.10 0.10
216 0.20 0.10 0.30 0.1 0.2 0.30 0.10 0 54 0 162 503 0 0 0.20 0.10 108.00 53.95 156.74 1425.00 0.13 0.13
225 0.20 0.10 0.30 0.1 0.2 0.30 0.10 0 54 0 216 503 0 0 0.20 0.13 108.00 69.54 195.20 1425.00 0.15 0.15
234 0.40 0.10 0.50 0.1 0.3 0.40 0.10 0 54 0 270 503 0 0 0.30 0.15 162.00 79.32 277.88 1425.00 0.18 0.18
243 0.50 0.41 0.91 0.2 0.4 0.60 0.20 0 108 0 378 503 0 0 0.40 0.18 216.00 98.04 395.84 1425.00 0.22 0.22
252 1.77 0.10 1.87 0.5 1.43 1.93 0.50 0 270 0 648 503 145 0.27 1.43 0.22 772.20 121.23 1046.81 1425.00 0.40 0.67
261 0.30 0.00 0.30 0.1 0.2 0.30 0.10 0.27 54 145 557 503 54 0.1 0.20 0.40 108.00 217.28 937.53 1425.00 0.38 0.48
270 0.20 0.00 0.20 0.1 0.1 0.20 0.10 0.10 54 54 557 503 54 0.1 0.10 0.38 54.00 203.37 788.15 1425.00 0.34 0.44
279 0.10 0.00 0.10 0.1 0.1 0.20 0.10 0.10 54 54 557 503 54 0.1 0.10 0.34 54.00 183.26 658.89 1425.00 0.30 0.40
288 0.10 0.00 0.10 0 0.1 0.10 0.00 0.10 0 54 503 503 0 0 0.10 0.30 54.00 164.59 548.31 1425.00 0.27 0.27
297 0.10 0.00 0.10 0 0.1 0.10 0.00 0.00 0 0 503 503 0 0 0.10 0.27 54.00 147.41 454.90 1425.00 0.24 0.24
306 0.10 0.00 0.10 0 0.1 0.10 0.00 0 0 0 503 503 0 0 0.10 0.24 54.00 131.78 377.12 1425.00 0.22 0.22
315 0.10 0.00 0.10 0 0.1 0.10 0.00 0 0 0 503 503 0 0 0.10 0.22 54.00 117.76 313.36 1425.00 0.20 0.20
324 0.10 0.00 0.10 0 0.1 0.10 0.00 0 0 0 503 503 0 0 0.10 0.20 54.00 105.37 261.99 1425.00 0.18 0.18
333 0.10 0.00 0.10 0 0.1 0.10 0.00 0 0 0 503 503 0 0 0.10 0.18 54.00 94.64 221.35 1425.00 0.16 0.16
342 0.10 0.00 0.10 0 0 0.00 0.00 0 0 0 503 503 0 0 0.00 0.16 0.00 85.54 135.81 1425.00 0.12 0.12
351 0.00 0.00 0.00 0 0 0.00 0.00 0 0 0 503 503 0 0 0.00 0.12 0.00 63.81 72.01 1425.00 0.08 0.08
360 0.00 0.00 0.00 0 0 0.00 0.00 0 0 0 503 503 0 0 0.00 0.08 0.00 43.60 28.40 1425.00 0.05 0.05
369 0.00 0.00 0.00 0 0 0.00 0.00 0 0 0 503 503 0 0 0.00 0.05 0.00 24.95 3.45 1425.00 0.00 0.00
Total
Mitigated
Outflow
POC #1
Combo A+ H Post‐
DevelopmentCombo A+H Pre‐Development SubArea A Mitigated Output
Time
SubArea H Mitigated Output
21
Appendix H – Hydrology Map – Pre‐Construction
22
Appendix I – Hydrology Map – Post Construction
23
Appendix J – TRWE Detention Analysis at POC 2
Prepared by;
_________________________
Tory R. Walker, PE
R.C.E. 45005
TECHNICAL MEMORANDUM
for
Hope Elementary School
100-Year Storm Detention at POC 2
City of Carlsbad, California
Prepared for:
FPL and Associates
Attn: Alan Wing-Chi Lee, P.E.
30 Corporate Park, Suite 401
Irvine, CA 92026
August 2022
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page i Job # 657-01
TABLE OF CONTENTS
1. INTRODUCTION .................................................................................................................................... 1
2. GENERAL HYDROLOGY APPROACH ................................................................................................. 1
2.1. Point of Compliance .................................................................................................................. 1
2.2. Runoff Hydrograph Development ............................................................................................ 2
2.3. Rainfall Distribution ...................................................................................................................... 2
3. SWMM MODELING APPROACH ........................................................................................................ 3
3.1. LID Routing Considerations ........................................................................................................ 3
3.2. SDCHM Rational Method Hydrograph SWMM Input .............................................................. 4
4. SWMM RESULTS .................................................................................................................................... 4
5. CONCLUSION ...................................................................................................................................... 5
6. REFERENCES ......................................................................................................................................... 5
TABLES
Table 1 | Summary of Peak Flow Results ................................................................................................. 4
ATTACHMENTS
ATTACHMENT 1 Pre-Project and Post-Project Hydrology Exhibits
ATTACHMENT 2 Precipitation and Rational Method Hydrology and Hydrograph Data
ATTACHMENT 3 Storage and Rating Curves
ATTACHMENT 4 SWMM Input Data
ATTACHMENT 5 SWMM Summary Report
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 1 Job # 657-01
1. INTRODUCTION
This technical memorandum is based on the hydrologic model used in the companion technical
memorandum “Hope Elementary School Hydromodification Management at POC 2” (HMP
Study) by Tory R. Walker Engineering (TRWE). Pre-project and post-project 100-year, 6-hour
hydrographs were generated to demonstrate that the proposed flow control facility mitigates
the post-project peak flow to a rate that does not exceed the pre-project peak flow at point of
compliance (POC) 2.
The hydrologic parameters were obtained using the values established by FPL and Associates in
the project-specific drainage report titled “Drainage Study, Hope Elementary School (ES).” The
Rational Method Hydrograph procedure was selected to construct the hydrographs in
accordance with the San Diego County Hydrology Manual (SDCHM), as all drainage areas are
less than one square mile. Hydraulic routing was performed in the Environmental Protection
Agency (EPA) Storm Water Management Model (SWMM).
2. GENERAL HYDROLOGY APPROACH
The project proposes to modernize the school campus through the addition of new classrooms,
hardscape, and blacktop expansion. A location map is included in the report attachments.
The site is bounded by Tamarack Avenue on the east and open space canyons on the north,
south and west. The pre-project site is made up of rooftops, hardscape, blacktop, and
landscaped areas. The post-project improvements will result in an increase to the acreage and
imperviousness of the area tributary to the northern outfall (POC 2). Therefore, TRWE was tasked
with exclusively analyzing increased runoff at POC 2 based upon the hydrologic parameters
established by FPL and Associates, Inc. in the project-specific drainage report.
2.1. Point of Compliance
POC 2 has been identified as the northern existing outfall located near the toe of the existing
slope along the northern property boundary. In the pre-project condition, the area tributary to
POC 2, drainage management areas (DMAs) N and P, drain northerly to POC 2 via overland
flow. In the post-project condition, the area tributary to POC 2 increases because of a proposed
reconfiguration to the existing onsite storm drain necessary for the purposes of intercepting the
requisite level of stormwater runoff volume for compliance with the prevailing pollutant control
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 2 Job # 657-01
requirements set forth by the City of Carlsbad BMP Design Manual. The result is that both newly
created and replaced impervious areas—as well as existing paved areas within the easterly
drive aisle and loading zone—comingle and drain to a biofiltration basin near the northeast
quadrant of the property via a combination of piped and overland flow. Runoff volume from
these DMAs is routed to the proposed basin, then discharge to POC 2 after attenuation, whereas
runoff from several undisturbed DMAs bypasses the basin and co-mingles with detained outflow
at the POC. Flows exit the existing outfall at POC 2 and continue downstream into the existing
canyon.
2.2. Runoff Hydrograph Development
For pre-project and post-project conditions, the runoff hydrograph was calculated using the
SDCHM Rational Method Hydrograph procedure (see results in Appendix 2). Each peak at each
time interval is equal to:
Q = CIA
Where: Q = peak discharge (cfs)
C = runoff coefficient
I = average rainfall intensity, taken at the time of concentration (in/hr)
A = drainage area (ac)
These hydrographs (see Appendix 2) were input into the SWMM model. Conservative times of
concentration were assumed for the pre-project and post-project DMAs (ten minutes for the
pre-project drainage area, and ten and five minutes for the undetained and detained post-
project drainage areas, respectively).
2.3. Rainfall Distribution
Rainfall was developed using the following SDCHM Intensity-Duration equation:
I = 7.44P6 D-0.645
Where: P6 = adjusted 6-hour storm rainfall amount (in)
D = duration, taken at the time of concentration (min)
However, longer durations (up to 360 minutes) were used to build the complete hyetograph
(precipitation distribution for the 100-year, 6-hour storm event). The 6-hour storm was distributed
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 3 Job # 657-01
according to the SDCHM nested storm pattern, where the peak precipitation starts four hours
after the beginning of the storm (see intensity tables in Appendix 2). Additionally, SWMM can
only use whole numbers as hydrograph time intervals (i.e., 1, 5, 10, 15, or 30 minutes). Therefore,
the respective time of concentration for each pre-project and post-project drainage area was
used as the duration value at each time step to create the corresponding runoff hydrograph.
3. SWMM MODELING APPROACH
As the post-project site hydrology—complete with the proposed biofiltration basin and
integrated flow control facility—has already been modeled in SWMM for hydromodification
management flow control facility design, the SWMM model was restructured to route the 100-
year, 6-hour peak flow. In order to restructure the model for Q100 analysis, changes to several
model inputs were required; therefore, a general explanation of the necessary changes follows.
3.1. LID Routing Considerations
SWMM was selected to route the 100-year peak flow because SWMM can route runoff
hydrographs through a biofiltration BMP via its built-in LID module feature. The SWMM LID module
produces more accurate LID routing results than other software. The SWMM LID module
accounts for detailed routing of the following: surface ponding, amended soil infiltration, gravel
storage detention, and underdrain outflow.
Once the LID surface ponding storage volume reaches its capacity, excess runoff volume is sent
to the system outlet. Excess runoff volume discharged in this fashion may be appropriate in
select hydromodification modeling cases because influent runoff rates and corresponding
surface ponding volumes are not likely to experience significant changes between calculated
time steps (when time steps are hourly). However, the degree to which the LID underdrain
discharge and POC discharge rates are affected depends on the surface ponding and outlet
structure configurations; therefore, in order to avoid introducing uncertainties into the
biofiltration basin modeling, the Modified Puls Method was selected to route ponded depths
exceeding the LID surface ponding depth.
In order to account for surface routing, the biofiltration basin is divided in two portions: LID
surface ponding and overflow riser routing. The LID surface ponding is described by the ponded
volume between the amended soil surface and the invert of the lowest surface discharge outlet
in the overflow riser. The overflow riser routing begins at the invert of the lowest surface discharge
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 4 Job # 657-01
outlet in the overflow riser and extends upward to the top of basin. For LID surface ponding,
ponded volumes infiltrate through the amended soil and gravel storage layers and then
discharge through the underdrain system directly to the POC. For the overflow riser routing, a
storage curve (ponded depth vs. basin area) and rating curve (ponded depth vs. discharge)
are required in order for ponded volume to be routed through the overflow riser. The storage
and rating curves are provided in Appendix 3; further information and flow control facility
structure details are provided in the HMP Study.
3.2. SDCHM Rational Method Hydrograph SWMM Input
SWMM is a physically based, discrete-time simulation model that employs principles of
conservation of mass, energy, and momentum to route storm runoff. Therefore, SWMM does not
calculate the Rational Method hydrograph. As a working solution, TRWE developed an
appropriate method to route the Rational Method hydrograph through the SWMM model.
The 100-year, 6-hour hydrograph was constructed for the areas draining to POC 2 in the pre-
project and post-project conditions. Input hydrographs were inserted into the SWMM model for
hydraulic routing through the basin. No rainfall-runoff relationships were calculated in SWMM
due to the externally derived runoff hydrograph procedure.
4. SWMM RESULTS
The results show that the proposed biofiltration basin reduces the post-project peak flow below
pre-project conditions. Results are displayed in Table 1. A pre- vs. post-project hydrograph
comparison is illustrated in Figure 1. From this analysis, it is clearly presented that the biofiltration
basin not only satisfies hydromodification criteria, but also reduce the post-project peak flow
below the pre-project level for the 100-year, 6-hour synthetic storm.
Table 1 | Summary of Peak Flow Results
POC Pre-Project Peak
Flow (cfs)
Post-Project
Undetained
Peak Flow (cfs)
Post-Project
Detained Peak
Flow (cfs)
Difference (cfs)
2 6.4 19.2 5.4 -1.0
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 5 Job # 657-01
5. CONCLUSION
The proposed biofiltration basin configuration mitigates the post-project peak flow to a rate that
does not exceed the pre-project peak flow at POC 2.
6. REFERENCES
1. California Regional Water Quality Control Board, San Diego Region. (2016). Order No. R9-
2013-0001 (as Amended by Order Nos. R9-2015-0001 and R9-2015-0100), National
Pollutant Discharge Elimination System (NPDES) Permit and Waste Discharge
Requirements for Discharges from the Municipal Separate Storm Sewer Systems (MS4s)
Draining the Watersheds within the San Diego Region.
2. City of Carlsbad. (2016). Engineering Standards, Volume 5: Carlsbad BMP Design Manual.
3. County of San Diego. (2003). Hydrology Manual.
6.38 cfs
19.2 cfs
5.41 cfs
0
2
4
6
8
10
12
14
16
18
20
Pe
a
k
F
l
o
w
(
c
f
s
)
Elapsed Time (HH:MM)
100-YEAR 6-HOUR STORM (POC-2)
EXISTING CONDITION PROPOSED (UNMITIGATED)PROPOSED (MITIGATED)
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 6 Job # 657-01
4. FPL and Associates. (2021). Drainage Study, Hope Elementary School (ES).
5. FPL and Associates. (2021). Priority Development Project Storm Water Quality
Management Plan for Hope Elementary School New Classroom Building/Modernization,
Project ID PD-2020-0049, Drawing No. G-528-2A.
6. Maidment, D. (1992). Handbook of Hydrology. McGraw Hill.
7. Tory R. Walker Engineering. (2012). Review and Analysis of San Diego County
Hydromodification Management Plan (HMP): Assumptions, Criteria, Methods, & Modeling
Tools – Prepared for the Cities of San Marcos, Oceanside & Vista.
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 7 Job # 657-01
ATTACHMENT 1
Pre-Project and Post-Project Hydrology Exhibits
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 8 Job # 657-01
ATTACHMENT 2
Precipitation and Rational Method Hydrology and Hydrograph Data
Hydrologic Soil Group—San Diego County Area, California
(Hope Elementary School - HSG)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
11/2/2021
Page 1 of 4
36
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471420 471470 471520 471570 471620 471670 471720
471420 471470 471520 471570 471620 471670 471720
33° 10' 23'' N
11
7
°
1
8
'
2
4
'
'
W
33° 10' 23'' N
11
7
°
1
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33° 10' 9'' N
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'
2
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33° 10' 9'' N
11
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°
1
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'
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W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84
0 100 200 400 600
Feet
0 30 60 120 180
Meters
Map Scale: 1:2,100 if printed on A portrait (8.5" x 11") sheet.
Soil Map may not be valid at this scale.
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Rating Polygons
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Lines
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Points
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: San Diego County Area, California
Survey Area Data: Version 16, Sep 13, 2021
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Jan 24, 2020—Feb
12, 2020
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Hydrologic Soil Group—San Diego County Area, California
(Hope Elementary School - HSG)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
11/2/2021
Page 2 of 4
Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
DaF Diablo clay, 30 to 50
percent slopes, warm
MAAT, MLRA 20
C 10.1 53.5%
LeE3 Las Flores loamy fine
sand, 9 to 30 percent
slopes, severely
eroded
D 8.7 46.4%
SbC Salinas clay loam, 2 to 9
percent slopes
C 0.0 0.1%
Totals for Area of Interest 18.8 100.0%
Hydrologic Soil Group—San Diego County Area, California Hope Elementary School - HSG
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
11/2/2021
Page 3 of 4
Description
Hydrologic soil groups are based on estimates of runoff potential. Soils are
assigned to one of four groups according to the rate of water infiltration when the
soils are not protected by vegetation, are thoroughly wet, and receive
precipitation from long-duration storms.
The soils in the United States are assigned to four groups (A, B, C, and D) and
three dual classes (A/D, B/D, and C/D). The groups are defined as follows:
Group A. Soils having a high infiltration rate (low runoff potential) when
thoroughly wet. These consist mainly of deep, well drained to excessively
drained sands or gravelly sands. These soils have a high rate of water
transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately deep or deep, moderately well drained or well
drained soils that have moderately fine texture to moderately coarse texture.
These soils have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist
chiefly of soils having a layer that impedes the downward movement of water or
soils of moderately fine texture or fine texture. These soils have a slow rate of
water transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential) when
thoroughly wet. These consist chiefly of clays that have a high shrink-swell
potential, soils that have a high water table, soils that have a claypan or clay
layer at or near the surface, and soils that are shallow over nearly impervious
material. These soils have a very slow rate of water transmission.
If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is
for drained areas and the second is for undrained areas. Only the soils that in
their natural condition are in group D are assigned to dual classes.
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Hydrologic Soil Group—San Diego County Area, California Hope Elementary School - HSG
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
11/2/2021
Page 4 of 4
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 9 Job # 657-01
ATTACHMENT 3
Storage and Rating Curves
Stage-Area for BMP_B
Depth (ft)Elevation (ft)Area (ft2)Volume (ft3)
0.00 216.00 3204 0 BIOFILTRATION (1)
0.08 216.08 3259 269
0.17 216.17 3314 543
0.25 216.25 3369 822
0.33 216.33 3424 1105
0.42 216.42 3479 1392
0.50 216.50 3534 1684
0.58 216.58 3589 1981
0.67 216.67 3644 2282
0.75 216.75 3698 2588
0.83 216.83 3753 2899
0.92 216.92 3808 3214
1.00 217.00 3863 3534 SURFACE OUTLET (2)
1.08 217.08 3918 3858
1.17 217.17 3973 4187
1.25 217.25 4028 4520
1.33 217.33 4083 4858
1.42 217.42 4138 5200
1.50 217.50 4193 5548
1.58 217.58 4252 5899
1.67 217.67 4314 6256
1.75 217.75 4377 6618
1.83 217.83 4442 6986
1.92 217.92 4508 7359
2.00 218.00 4574 7737
2.08 218.08 4641 8121
2.17 218.17 4708 8511
2.25 218.25 4776 8906
2.33 218.33 4843 9307
2.42 218.42 4910 9713
2.50 218.50 4977 10125
2.58 218.58 5044 10543
2.67 218.67 5110 10966
2.75 218.75 5174 11394
2.83 218.83 5238 11828
2.92 218.92 5300 12267
3.00 219.00 5358 12711
3.08 219.08 5413 13160
3.17 219.17 5468 13613
3.25 219.25 5523 14071
3.33 219.33 5578 14534
3.42 219.42 5633 15001
3.50 219.50 5688 15473
3.58 219.58 5743 15949
3.67 219.67 5798 16430
3.75 219.75 5853 16915
3.83 219.83 5908 17405
3.92 219.92 5963 17900
4.00 220.00 6018 18399
Effective Depth:13.23 in
BMP B DISCHARGE RATING CURVE
Notes:
Diameter:1.750 inches Quantity:Quantity:1 h taken as total depth above the invert of the lowest discharge opening.
Quantity:1 Invert Elevation:ft Invert Elevation:2.08 ft Hw = height of slot/weir invert above basin bottom
Invert Elevation:0.000 ft Width:ft Length:12.00 ft
Type Vertical Height:in Hw:219.08 ft
0.000 ft Type Sharp
Hw:217.00 ft
Diameter:inches Quantity:Invert Elevation:ft Basin Footprint:sf
Quantity:Invert Elevation:ft Length:ft Infiltration Rate in/hr
Invert Elevation:ft Width:ft Breadth:ft Factor of Safety
Height:in Hw:217.00 ft Design Infiltration Rate in/hr
0.000 ft Type Sharp
Hw:217.00 ft
Invert Elevation:217.00 ft
Orifice
Discharge
Coefficient
Orifice Flow Weir Flow Q control (cfs)
Orifice
Discharge
Coefficient
Orifice Flow Weir Flow Q control (cfs)
Orifice
Discharge
Coefficient
Orifice Flow
Weir
Discharge
Coefficient
Weir Flow Q control (cfs)
Orifice
Discharge
Coefficient
Orifice Flow
Weir
Discharge
Coefficient
Weir Flow Q control (cfs)
Weir
Discharge
Coefficient
Q (cfs)
Weir
Discharge
Coefficient
Q (cfs)
217.00 0.000 N/A N/A 0.000 0.000 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.000
217.04 0.042 N/A N/A 0.002 0.002 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.002
217.08 0.083 N/A N/A 0.008 0.008 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.008
217.13 0.125 N/A N/A 0.016 0.016 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.016
217.17 0.167 0.609 0.025 N/A 0.025 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.025
217.21 0.208 0.609 0.030 N/A 0.030 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.030
217.25 0.250 0.609 0.034 N/A 0.034 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.034
217.29 0.292 0.609 0.038 N/A 0.038 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.038
217.33 0.333 0.609 0.042 N/A 0.042 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.042
217.38 0.375 0.609 0.045 N/A 0.045 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.045
217.42 0.417 0.609 0.048 N/A 0.048 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.048
217.46 0.458 0.609 0.051 N/A 0.051 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.051
217.50 0.500 0.607 0.053 N/A 0.053 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.053
217.54 0.542 0.607 0.056 N/A 0.056 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.056
217.58 0.583 0.606 0.058 N/A 0.058 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.058
217.63 0.625 0.606 0.060 N/A 0.060 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.060
217.67 0.667 0.606 0.063 N/A 0.063 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.063
217.71 0.708 0.606 0.065 N/A 0.065 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.065
217.75 0.750 0.606 0.067 N/A 0.067 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.067
217.79 0.792 0.605 0.069 N/A 0.069 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.069
217.83 0.833 0.605 0.071 N/A 0.071 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.071
217.88 0.875 0.604 0.072 N/A 0.072 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.072
217.92 0.917 0.604 0.074 N/A 0.074 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.074
217.96 0.958 0.604 0.076 N/A 0.076 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.076
218.00 1.000 0.603 0.078 N/A 0.078 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.078
218.04 1.042 0.603 0.080 N/A 0.080 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.080
218.08 1.083 0.603 0.081 N/A 0.081 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.081
218.13 1.125 0.603 0.083 N/A 0.083 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.083
218.17 1.167 0.603 0.085 N/A 0.085 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.085
218.21 1.208 0.603 0.086 N/A 0.086 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.086
218.25 1.250 0.603 0.088 N/A 0.088 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.088
218.29 1.292 0.602 0.089 N/A 0.089 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.089
218.33 1.333 0.602 0.091 N/A 0.091 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.091
218.38 1.375 0.602 0.092 N/A 0.092 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.092
218.42 1.417 0.602 0.094 N/A 0.094 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.094
218.46 1.458 0.602 0.095 N/A 0.095 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.095
218.50 1.500 0.601 0.096 N/A 0.096 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.096
218.54 1.542 0.601 0.098 N/A 0.098 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.098
218.58 1.583 0.601 0.099 N/A 0.099 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.099
218.63 1.625 0.601 0.100 N/A 0.100 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.100
218.67 1.667 0.601 0.102 N/A 0.102 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.102
218.71 1.708 0.601 0.103 N/A 0.103 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.103
Elevation
(ft)
Lowest Orifice Lower Slot Lower Weir
Upper Orifice Upper Slot Emergency Weir
Absolute Invert Elevation of Lowest Discharge Opening
h
(ft)
LOWEST ORIFICE UPPER ORIFICE LOWER SLOT LOWER WEIR EMERGENCY WEIR
Q inf
(cfs)
Q TOTAL
(cfs)
Infiltration
UPPER SLOT
0.000
0.500
1.000
1.500
2.000
2.500
3.000
3.500
0.000 5.000 10.000 15.000 20.000 25.000 30.000 35.000 40.000
St
a
g
e
(
f
t
)
Discharge (cfs)
Rating Curve
BMP B DISCHARGE RATING CURVE
Notes:
Diameter:1.750 inches Quantity:Quantity:1 h taken as total depth above the invert of the lowest discharge opening.
Quantity:1 Invert Elevation:ft Invert Elevation:2.08 ft Hw = height of slot/weir invert above basin bottom
Invert Elevation:0.000 ft Width:ft Length:12.00 ft
Type Vertical Height:in Hw:219.08 ft
0.000 ft Type Sharp
Hw:217.00 ft
Diameter:inches Quantity:Invert Elevation:ft Basin Footprint:sf
Quantity:Invert Elevation:ft Length:ft Infiltration Rate in/hr
Invert Elevation:ft Width:ft Breadth:ft Factor of Safety
Height:in Hw:217.00 ft Design Infiltration Rate in/hr
0.000 ft Type Sharp
Hw:217.00 ft
Invert Elevation:217.00 ft
Orifice
Discharge
Coefficient
Orifice Flow Weir Flow Q control (cfs)
Orifice
Discharge
Coefficient
Orifice Flow Weir Flow Q control (cfs)
Orifice
Discharge
Coefficient
Orifice Flow
Weir
Discharge
Coefficient
Weir Flow Q control (cfs)
Orifice
Discharge
Coefficient
Orifice Flow
Weir
Discharge
Coefficient
Weir Flow Q control (cfs)
Weir
Discharge
Coefficient
Q (cfs)
Weir
Discharge
Coefficient
Q (cfs)
Elevation
(ft)
Lowest Orifice Lower Slot Lower Weir
Upper Orifice Upper Slot Emergency Weir
Absolute Invert Elevation of Lowest Discharge Opening
h
(ft)
LOWEST ORIFICE UPPER ORIFICE LOWER SLOT LOWER WEIR EMERGENCY WEIR
Q inf
(cfs)
Q TOTAL
(cfs)
Infiltration
UPPER SLOT
0.000
0.500
1.000
1.500
2.000
2.500
3.000
3.500
0.000 5.000 10.000 15.000 20.000 25.000 30.000 35.000 40.000
St
a
g
e
(
f
t
)
Discharge (cfs)
Rating Curve
218.75 1.750 0.601 0.104 N/A 0.104 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.104
218.79 1.792 0.601 0.106 N/A 0.106 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.106
218.83 1.833 0.601 0.107 N/A 0.107 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.107
218.88 1.875 0.601 0.108 N/A 0.108 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.108
218.92 1.917 0.601 0.109 N/A 0.109 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.109
218.96 1.958 0.601 0.111 N/A 0.111 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.111
219.00 2.000 0.601 0.112 N/A 0.112 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.112
219.04 2.042 0.601 0.113 N/A 0.113 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 0.113
219.08 2.083 0.600 0.114 N/A 0.114 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.270 0.000 N/A N/A N/A 0.114
219.13 2.125 0.600 0.115 N/A 0.115 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.270 0.334 N/A N/A N/A 0.449
219.17 2.167 0.600 0.116 N/A 0.116 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.270 0.944 N/A N/A N/A 1.060
219.21 2.208 0.600 0.118 N/A 0.118 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.270 1.734 N/A N/A N/A 1.852
219.25 2.250 0.600 0.119 N/A 0.119 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.270 2.670 N/A N/A N/A 2.789
219.29 2.292 0.600 0.120 N/A 0.120 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.270 3.732 N/A N/A N/A 3.852
219.33 2.333 0.600 0.121 N/A 0.121 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.270 4.906 N/A N/A N/A 5.027
219.38 2.375 0.600 0.122 N/A 0.122 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 6.182 N/A N/A N/A 6.304
219.42 2.417 0.600 0.123 N/A 0.123 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 7.553 N/A N/A N/A 7.676
219.46 2.458 0.600 0.124 N/A 0.124 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 9.013 N/A N/A N/A 9.137
219.50 2.500 0.600 0.125 N/A 0.125 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 10.556 N/A N/A N/A 10.682
219.54 2.542 0.600 0.126 N/A 0.126 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 12.179 N/A N/A N/A 12.305
219.58 2.583 0.600 0.127 N/A 0.127 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 13.877 N/A N/A N/A 14.005
219.63 2.625 0.600 0.129 N/A 0.129 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 15.648 N/A N/A N/A 15.777
219.67 2.667 0.600 0.130 N/A 0.130 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 17.488 N/A N/A N/A 17.618
219.71 2.708 0.600 0.131 N/A 0.131 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 19.395 N/A N/A N/A 19.526
219.75 2.750 0.600 0.132 N/A 0.132 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 21.368 N/A N/A N/A 21.499
219.79 2.792 0.600 0.133 N/A 0.133 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 23.402 N/A N/A N/A 23.535
219.83 2.833 0.600 0.134 N/A 0.134 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 25.498 N/A N/A N/A 25.631
219.88 2.875 0.600 0.135 N/A 0.135 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.271 27.653 N/A N/A N/A 27.787
219.92 2.917 0.600 0.136 N/A 0.136 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.272 29.865 N/A N/A N/A 30.000
219.96 2.958 0.600 0.137 N/A 0.137 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.272 32.133 N/A N/A N/A 32.270
220.00 3.000 0.600 0.138 N/A 0.138 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 3.272 34.456 N/A N/A N/A 34.594
BMP_B
ABMP 3204.0 sq-ft
Cg 0.61
Dorif 0.875 in
Aorif 0.00418 sq-ft
CSWMM 0.0796 s-(in)^0.5/hr2
0.017703 cfs
Hgravel 0.75 ft
Hgravel 9 in
Hsoil 1.75 ft
Hsoil 21 in
Hsurface 1 ft
Hsurface 12 in
Hdesign-SWMM 3.500 ft
42 in
Hdesign 3.464 ft
41.5625 in
Qorif-classic 0.03824 cfs
Qorif-SWMM 0.03824 cfs
Qdiversion 0.03824 cfs
Using
Hdesign-SWMM
Rational Method Hydrograph Calculations
for Post Developed Conditions
Hope Elementary School, Carlsbad CA
Q100=16.06 cfs
Tc=5 min C=0.88
#= 72 P100,6=2.8 in A=2.46 acres
(7.44*P6*D^-.645)(I*D/60)(V1-V0)(∆V/∆T)(Q=ciA)(Re-ordered)
D I VOL ∆VOL I (INCR)Q VOL ORDINATE#(MIN)(IN/HR)(IN)(IN)(IN/HR)(CFS)(CF)SUM=
0 0 0.00 0.00 0.61 7.38 16.06 4819
1 5 7.38 0.61 0.17 2.06 4.44 1333 0.36
2 10 4.72 0.79 0.12 1.46 3.15 946 0.36
3 15 3.63 0.91 0.10 1.17 2.53 759 0.37
4 20 3.02 1.01 0.08 0.99 2.15 644 0.37
5 25 2.61 1.09 0.07 0.87 1.89 566 0.38
6 30 2.32 1.16 0.07 0.78 1.69 508 0.38
7 35 2.10 1.23 0.06 0.71 1.54 463 0.39
8 40 1.93 1.29 0.05 0.66 1.42 427 0.40
9 45 1.79 1.34 0.05 0.61 1.32 397 0.41
10 50 1.67 1.39 0.05 0.57 1.24 372 0.41
11 55 1.57 1.44 0.05 0.54 1.17 351 0.42
12 60 1.49 1.49 0.04 0.51 1.11 333 0.42
13 65 1.41 1.53 0.04 0.49 1.06 317 0.43
14 70 1.34 1.57 0.04 0.47 1.01 302 0.44
15 75 1.29 1.61 0.04 0.45 0.97 290 0.45
16 80 1.23 1.65 0.04 0.43 0.93 278 0.46
17 85 1.19 1.68 0.03 0.41 0.89 268 0.47
18 90 1.14 1.72 0.03 0.40 0.86 258 0.48
19 95 1.10 1.75 0.03 0.39 0.83 250 0.49
20 100 1.07 1.78 0.03 0.37 0.81 242 0.50
21 105 1.04 1.81 0.03 0.36 0.78 235 0.51
22 110 1.00 1.84 0.03 0.35 0.76 228 0.52
23 115 0.98 1.87 0.03 0.34 0.74 221 0.54
24 120 0.95 1.90 0.03 0.33 0.72 216 0.55
25 125 0.93 1.93 0.03 0.32 0.70 210 0.57
26 130 0.90 1.95 0.03 0.32 0.68 205 0.58
27 135 0.88 1.98 0.03 0.31 0.67 200 0.60
28 140 0.86 2.01 0.03 0.30 0.65 196 0.61
29 145 0.84 2.03 0.02 0.30 0.64 191 0.64
30 150 0.82 2.06 0.02 0.29 0.62 187 0.65
31 155 0.81 2.08 0.02 0.28 0.61 183 0.68
32 160 0.79 2.10 0.02 0.28 0.60 180 0.70
33 165 0.77 2.13 0.02 0.27 0.59 176 0.74
34 170 0.76 2.15 0.02 0.27 0.58 173 0.76
35 175 0.74 2.17 0.02 0.26 0.57 170 0.81
36 180 0.73 2.19 0.02 0.26 0.56 167 0.83
37 185 0.72 2.22 0.02 0.25 0.55 164 0.89
38 190 0.71 2.24 0.02 0.25 0.54 161 0.93
39 195 0.69 2.26 0.02 0.24 0.53 158 1.01
40 200 0.68 2.28 0.02 0.24 0.52 156 1.06
41 205 0.67 2.30 0.02 0.24 0.51 153 1.17
42 210 0.66 2.32 0.02 0.23 0.50 151 1.24
RM-Hydrograph_BMP B 8/9/2022
Rational Method Hydrograph Calculations
for Post Developed Conditions
Hope Elementary School, Carlsbad CA
D I VOL ∆VOL I (INCR)Q VOL ORDINATE#(MIN)(IN/HR)(IN)(IN)(IN/HR)(CFS)(CF)SUM=
43 215 0.65 2.34 0.02 0.23 0.50 149 1.42
44 220 0.64 2.36 0.02 0.23 0.49 147 1.54
45 225 0.63 2.37 0.02 0.22 0.48 145 1.89
46 230 0.62 2.39 0.02 0.22 0.48 143 2.15
47 235 0.62 2.41 0.02 0.22 0.47 141 3.15
48 240 0.61 2.43 0.02 0.21 0.46 139 4.44
49 245 0.60 2.45 0.02 0.21 0.46 137 16.06
50 250 0.59 2.47 0.02 0.21 0.45 135 2.53
51 255 0.58 2.48 0.02 0.21 0.44 133 1.69
52 260 0.58 2.50 0.02 0.20 0.44 132 1.32
53 265 0.57 2.52 0.02 0.20 0.43 130 1.11
54 270 0.56 2.53 0.02 0.20 0.43 129 0.97
55 275 0.56 2.55 0.02 0.20 0.42 127 0.86
56 280 0.55 2.57 0.02 0.19 0.42 126 0.78
57 285 0.54 2.58 0.02 0.19 0.41 124 0.72
58 290 0.54 2.60 0.02 0.19 0.41 123 0.67
59 295 0.53 2.61 0.02 0.19 0.41 122 0.62
60 300 0.53 2.63 0.02 0.19 0.40 120 0.59
61 305 0.52 2.65 0.02 0.18 0.40 119 0.56
62 310 0.51 2.66 0.02 0.18 0.39 118 0.53
63 315 0.51 2.68 0.02 0.18 0.39 117 0.50
64 320 0.50 2.69 0.01 0.18 0.38 115 0.48
65 325 0.50 2.71 0.01 0.18 0.38 114 0.46
66 330 0.49 2.72 0.01 0.17 0.38 113 0.44
67 335 0.49 2.74 0.01 0.17 0.37 112 0.43
68 340 0.49 2.75 0.01 0.17 0.37 111 0.41
69 345 0.48 2.76 0.01 0.17 0.37 110 0.40
70 350 0.48 2.78 0.01 0.17 0.36 109 0.39
71 355 0.47 2.79 0.01 0.17 0.36 108 0.38
72 360 0.47 2.81 0.00 0.00 0.00 0 0.37
SUM=21852 cubic feet
0.50 acre-feet
Check:V = C*A*P6
V=0.50 acre-feet
OK
RM-Hydrograph_BMP B 8/9/2022
Rational Method Hydrograph Calculations
for Pre Developed Conditions
Hope Elementary School, Carlsbad, CA
Q100=6.38 cfs
Tc=10.00 min C=0.47
#= 36 P100,6=2.8 in A=2.83 acres
(7.44*P6*D^-.645)(I*D/60)(V1-V0)(∆V/∆T)(Q=ciA)(Re-ordered)
D I VOL ∆VOL I (INCR)Q VOL ORDINATE
#(MIN)(IN/HR)(IN)(IN)(IN/HR)(CFS)(CF)SUM=
0 0 0.00 0.00 0.79 4.72 6.38 3829
1 10 4.72 0.79 0.22 1.32 1.77 1059 0.22
2 20 3.02 1.01 0.16 0.93 1.25 752 0.23
3 30 2.32 1.16 0.12 0.75 1.01 603 0.24
4 40 1.93 1.29 0.11 0.64 0.85 512 0.24
5 50 1.67 1.39 0.09 0.56 0.75 450 0.25
6 60 1.49 1.49 0.08 0.50 0.67 403 0.26
7 70 1.34 1.57 0.08 0.46 0.61 368 0.27
8 80 1.23 1.65 0.07 0.42 0.57 339 0.28
9 90 1.14 1.72 0.07 0.39 0.53 316 0.29
10 100 1.07 1.78 0.06 0.37 0.49 296 0.30
11 110 1.00 1.84 0.06 0.35 0.47 279 0.32
12 120 0.95 1.90 0.05 0.33 0.44 264 0.33
13 130 0.90 1.95 0.05 0.31 0.42 252 0.35
14 140 0.86 2.01 0.05 0.30 0.40 240 0.37
15 150 0.82 2.06 0.05 0.29 0.38 230 0.40
16 160 0.79 2.10 0.05 0.27 0.37 221 0.42
17 170 0.76 2.15 0.04 0.26 0.35 213 0.47
18 180 0.73 2.19 0.04 0.26 0.34 205 0.49
19 190 0.71 2.24 0.04 0.25 0.33 198 0.57
20 200 0.68 2.28 0.04 0.24 0.32 192 0.61
21 210 0.66 2.32 0.04 0.23 0.31 186 0.75
22 220 0.64 2.36 0.04 0.22 0.30 181 0.85
23 230 0.62 2.39 0.04 0.22 0.29 176 1.25
24 240 0.61 2.43 0.04 0.21 0.29 171 1.77
25 250 0.59 2.47 0.03 0.21 0.28 167 6.38
26 260 0.58 2.50 0.03 0.20 0.27 163 1.01
27 270 0.56 2.53 0.03 0.20 0.26 159 0.67
28 280 0.55 2.57 0.03 0.19 0.26 155 0.53
29 290 0.54 2.60 0.03 0.19 0.25 152 0.44
30 300 0.53 2.63 0.03 0.18 0.25 149 0.38
31 310 0.51 2.66 0.03 0.18 0.24 146 0.34
32 320 0.50 2.69 0.03 0.18 0.24 143 0.31
33 330 0.49 2.72 0.03 0.17 0.23 140 0.29
34 340 0.49 2.75 0.03 0.17 0.23 137 0.26
35 350 0.48 2.78 0.03 0.17 0.22 135 0.25
36 360 0.47 2.81 0.00 0.00 0.00 0 0.23SUM=13581 cubic feet
0.31 acre-feet
Check:V = C*A*P6V=0.31 acre-feet
OK
RM-Hydrograph_DMA N - Pre 8/9/2022
Rational Method Hydrograph Calculations
for Post Developed Conditions
Hope Elementary School, Carlsbad CA
Q100=5.10 cfs
Tc=10 min C=0.42
#= 36 P100,6=2.8 in A=2.10 acres
(7.44*P6*D^-.645)(I*D/60)(V1-V0)(∆V/∆T)(Q=ciA)(Re-ordered)
D I VOL ∆VOL I (INCR)Q VOL ORDINATE
#(MIN)(IN/HR)(IN)(IN)(IN/HR)(CFS)(CF)SUM=
0 0 0.00 0.00 0.79 4.72 5.10 3059
1 10 4.72 0.79 0.22 1.32 1.16 697 0.15
2 20 3.02 1.01 0.16 0.93 0.82 494 0.15
3 30 2.32 1.16 0.12 0.75 0.66 397 0.16
4 40 1.93 1.29 0.11 0.64 0.56 337 0.16
5 50 1.67 1.39 0.09 0.56 0.49 296 0.17
6 60 1.49 1.49 0.08 0.50 0.44 265 0.17
7 70 1.34 1.57 0.08 0.46 0.40 242 0.18
8 80 1.23 1.65 0.07 0.42 0.37 223 0.18
9 90 1.14 1.72 0.07 0.39 0.35 208 0.19
10 100 1.07 1.78 0.06 0.37 0.32 195 0.20
11 110 1.00 1.84 0.06 0.35 0.31 184 0.21
12 120 0.95 1.90 0.05 0.33 0.29 174 0.22
13 130 0.90 1.95 0.05 0.31 0.28 165 0.23
14 140 0.86 2.01 0.05 0.30 0.26 158 0.24
15 150 0.82 2.06 0.05 0.29 0.25 151 0.26
16 160 0.79 2.10 0.05 0.27 0.24 145 0.28
17 170 0.76 2.15 0.04 0.26 0.23 140 0.31
18 180 0.73 2.19 0.04 0.26 0.23 135 0.32
19 190 0.71 2.24 0.04 0.25 0.22 131 0.37
20 200 0.68 2.28 0.04 0.24 0.21 126 0.40
21 210 0.66 2.32 0.04 0.23 0.20 123 0.49
22 220 0.64 2.36 0.04 0.22 0.20 119 0.56
23 230 0.62 2.39 0.04 0.22 0.19 116 0.82
24 240 0.61 2.43 0.04 0.21 0.19 113 1.16
25 250 0.59 2.47 0.03 0.21 0.18 110 5.10
26 260 0.58 2.50 0.03 0.20 0.18 107 0.66
27 270 0.56 2.53 0.03 0.20 0.17 105 0.44
28 280 0.55 2.57 0.03 0.19 0.17 102 0.35
29 290 0.54 2.60 0.03 0.19 0.17 100 0.29
30 300 0.53 2.63 0.03 0.18 0.16 98 0.25
31 310 0.51 2.66 0.03 0.18 0.16 96 0.23
32 320 0.50 2.69 0.03 0.18 0.16 94 0.20
33 330 0.49 2.72 0.03 0.17 0.15 92 0.19
34 340 0.49 2.75 0.03 0.17 0.15 90 0.17
35 350 0.48 2.78 0.03 0.17 0.15 89 0.16
36 360 0.47 2.81 0.00 0.00 0.00 0 0.15SUM=9473 cubic feet
0.22 acre-feet
Check:V = C*A*P6V=0.21 acre-feet
OK
RM-Hydrograph_DMA P+Q_POST 8/9/2022
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 10 Job # 657-01
ATTACHMENT 4
SWMM Input Data
[TITLE]
;;Project Title/Notes
Hope ES ‐ Proposed Condition Q100 ‐ POC 2
[OPTIONS]
;;Option Value
FLOW_UNITS CFS
INFILTRATION GREEN_AMPT
FLOW_ROUTING KINWAVE
LINK_OFFSETS DEPTH
MIN_SLOPE 0
ALLOW_PONDING NO
SKIP_STEADY_STATE NO
START_DATE 01/01/2000
START_TIME 00:00:00
REPORT_START_DATE 01/01/2000
REPORT_START_TIME 00:00:00
END_DATE 01/02/2000
END_TIME 00:00:00
SWEEP_START 01/01
SWEEP_END 12/31
DRY_DAYS 0
REPORT_STEP 00:01:00
WET_STEP 00:01:00
DRY_STEP 00:01:00
ROUTING_STEP 0:01:00
RULE_STEP 00:00:00
INERTIAL_DAMPING PARTIAL
NORMAL_FLOW_LIMITED BOTH
FORCE_MAIN_EQUATION H‐W
VARIABLE_STEP 0.75
LENGTHENING_STEP 0
MIN_SURFAREA 12.566
MAX_TRIALS 8
HEAD_TOLERANCE 0.005
SYS_FLOW_TOL 5
LAT_FLOW_TOL 5
MINIMUM_STEP 0.5
THREADS 1
[EVAPORATION]
;;Data Source Parameters
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
MONTHLY 0.030 0.050 0.080 0.110 0.130 0.150 0.150 0.130 0.110 0.080 0.040 0.020
DRY_ONLY NO
[RAINGAGES]
;;Name Format Interval SCF Source
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐ ‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐
FAKERAIN INTENSITY 1:00 1.0 TIMESERIES FAKERAIN
[SUBCATCHMENTS]
;;Name Rain Gage Outlet Area %Imperv Width %Slope CurbLen SnowPack
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
BMP_B FAKERAIN SURF_B 0.07355 0 10 1 0
[SUBAREAS]
;;Subcatchment N‐Imperv N‐Perv S‐Imperv S‐Perv PctZero RouteTo PctRouted
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐
BMP_B 0.012 0.15 0.05 0.1 25 OUTLET
[INFILTRATION]
;;Subcatchment Param1 Param2 Param3 Param4 Param5
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐
BMP_B 9 0.025 0.3 7 0
[LID_CONTROLS]
;;Name Type/Layer Parameters
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐
BMP_B BC
BMP_B SURFACE 13.23 0 0 0 5
BMP_B SOIL 21 0.4 0.2 0.1 5 5 1.5
BMP_B STORAGE 12 0.67 0.190 0 NO
BMP_B DRAIN 0.0585 0.5 3 6 0 0
[LID_USAGE]
;;Subcatchment LID Process Number Area Width InitSat FromImp ToPerv RptFile DrainTo
FromPerv
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
‐‐‐‐‐‐‐‐‐‐
BMP_B BMP_B 1 3203.84 0 0 100 0 * POC‐2_POST 0
[OUTFALLS]
;;Name Elevation Type Stage Data Gated Route To
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
POC‐2_PRE 0 FREE NO
DMA_CGNO_POST 0 FREE NO BMP_B
DMA_P+Q_POST 0 FREE NO
POC‐2_POST 0 FREE NO
[STORAGE]
;;Name Elev. MaxDepth InitDepth Shape Curve Type/Params SurDepth Fevap Psi Ksat IMD
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐
SURF_B 217 3 0 TABULAR SURF_1 0 1
[OUTLETS]
;;Name From Node To Node Offset Type QTable/Qcoeff Qexpon Gated
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐
OUTLET_B SURF_B POC‐2_POST 0 TABULAR/DEPTH OUT_1 NO
[INFLOWS]
;;Node Constituent Time Series Type Mfactor Sfactor Baseline Pattern
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐
POC‐2_PRE FLOW DMA_N_PRE FLOW 1.0 1.0
DMA_CGNO_POST FLOW DMA_CGNO_POST FLOW 1.0 1.0
DMA_P+Q_POST FLOW DMA_P+Q_POST FLOW 1.0 1.0
[CURVES]
;;Name Type X‐Value Y‐Value
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐
OUT_1 Rating 0.000 0.000
OUT_1 0.042 0.002
OUT_1 0.083 0.008
OUT_1 0.125 0.016
OUT_1 0.167 0.025
OUT_1 0.208 0.030
OUT_1 0.250 0.034
OUT_1 0.292 0.038
OUT_1 0.333 0.042
OUT_1 0.375 0.045
OUT_1 0.417 0.048
OUT_1 0.458 0.051
OUT_1 0.500 0.053
OUT_1 0.542 0.056
OUT_1 0.583 0.058
OUT_1 0.625 0.060
OUT_1 0.667 0.063
OUT_1 0.708 0.065
OUT_1 0.750 0.067
OUT_1 0.792 0.069
OUT_1 0.833 0.071
OUT_1 0.875 0.072
OUT_1 0.917 0.074
OUT_1 0.958 0.076
OUT_1 1.000 0.078
OUT_1 1.042 0.080
OUT_1 1.083 0.081
OUT_1 1.125 0.083
OUT_1 1.167 0.085
OUT_1 1.208 0.086
OUT_1 1.250 0.088
OUT_1 1.292 0.089
OUT_1 1.333 0.091
OUT_1 1.375 0.092
OUT_1 1.417 0.094
OUT_1 1.458 0.095
OUT_1 1.500 0.096
OUT_1 1.542 0.098
OUT_1 1.583 0.099
OUT_1 1.625 0.100
OUT_1 1.667 0.102
OUT_1 1.708 0.103
OUT_1 1.750 0.104
OUT_1 1.792 0.106
OUT_1 1.833 0.107
OUT_1 1.875 0.108
OUT_1 1.917 0.109
OUT_1 1.958 0.111
OUT_1 2.000 0.112
OUT_1 2.042 0.113
OUT_1 2.083 0.114
OUT_1 2.125 0.449
OUT_1 2.167 1.060
OUT_1 2.208 1.852
OUT_1 2.250 2.789
OUT_1 2.292 3.852
OUT_1 2.333 5.027
OUT_1 2.375 6.304
OUT_1 2.417 7.676
OUT_1 2.458 9.137
OUT_1 2.500 10.682
OUT_1 2.542 12.305
OUT_1 2.583 14.005
OUT_1 2.625 15.777
OUT_1 2.667 17.618
OUT_1 2.708 19.526
OUT_1 2.750 21.499
OUT_1 2.792 23.535
OUT_1 2.833 25.631
OUT_1 2.875 27.787
OUT_1 2.917 30.000
OUT_1 2.958 32.270
OUT_1 3.000 34.594
;
SURF_1 Storage 0.00 3863
SURF_1 0.08 3918
SURF_1 0.17 3973
SURF_1 0.25 4028
SURF_1 0.33 4083
SURF_1 0.42 4138
SURF_1 0.50 4193
SURF_1 0.58 4252
SURF_1 0.67 4314
SURF_1 0.75 4377
SURF_1 0.83 4442
SURF_1 0.92 4508
SURF_1 1.00 4574
SURF_1 1.08 4641
SURF_1 1.17 4708
SURF_1 1.25 4776
SURF_1 1.33 4843
SURF_1 1.42 4910
SURF_1 1.50 4977
SURF_1 1.58 5044
SURF_1 1.67 5110
SURF_1 1.75 5174
SURF_1 1.83 5238
SURF_1 1.92 5300
SURF_1 2.00 5358
SURF_1 2.08 5413
SURF_1 2.17 5468
SURF_1 2.25 5523
SURF_1 2.33 5578
SURF_1 2.42 5633
SURF_1 2.50 5688
SURF_1 2.58 5743
SURF_1 2.67 5798
SURF_1 2.75 5853
SURF_1 2.83 5908
SURF_1 2.92 5963
SURF_1 3.00 6018
[TIMESERIES]
;;Name Date Time Value
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐
FAKERAIN 1/1/2000 00:00 0
FAKERAIN 1/2/2000 00:00 0
;
DMA_N_PRE 1/1/2000 0:00 0
DMA_N_PRE 0:10 0.22
DMA_N_PRE 0:20 0.23
DMA_N_PRE 0:30 0.24
DMA_N_PRE 0:40 0.24
DMA_N_PRE 0:50 0.25
DMA_N_PRE 1:00 0.26
DMA_N_PRE 1:10 0.27
DMA_N_PRE 1:20 0.28
DMA_N_PRE 1:30 0.29
DMA_N_PRE 1:40 0.30
DMA_N_PRE 1:50 0.32
DMA_N_PRE 2:00 0.33
DMA_N_PRE 2:10 0.35
DMA_N_PRE 2:20 0.37
DMA_N_PRE 2:30 0.40
DMA_N_PRE 2:40 0.42
DMA_N_PRE 2:50 0.47
DMA_N_PRE 3:00 0.49
DMA_N_PRE 3:10 0.57
DMA_N_PRE 3:20 0.61
DMA_N_PRE 3:30 0.75
DMA_N_PRE 3:40 0.85
DMA_N_PRE 3:50 1.25
DMA_N_PRE 4:00 1.77
DMA_N_PRE 4:10 6.38
DMA_N_PRE 4:20 1.01
DMA_N_PRE 4:30 0.67
DMA_N_PRE 4:40 0.53
DMA_N_PRE 4:50 0.44
DMA_N_PRE 5:00 0.38
DMA_N_PRE 5:10 0.34
DMA_N_PRE 5:20 0.31
DMA_N_PRE 5:30 0.29
DMA_N_PRE 5:40 0.26
DMA_N_PRE 5:50 0.25
DMA_N_PRE 6:00 0.23
;
DMA_CGNO_POST 1/1/2000 0:00 0
DMA_CGNO_POST 0:05 0.36
DMA_CGNO_POST 0:10 0.36
DMA_CGNO_POST 0:15 0.37
DMA_CGNO_POST 0:20 0.37
DMA_CGNO_POST 0:25 0.38
DMA_CGNO_POST 0:30 0.38
DMA_CGNO_POST 0:35 0.39
DMA_CGNO_POST 0:40 0.40
DMA_CGNO_POST 0:45 0.41
DMA_CGNO_POST 0:50 0.41
DMA_CGNO_POST 0:55 0.42
DMA_CGNO_POST 1:00 0.42
DMA_CGNO_POST 1:05 0.43
DMA_CGNO_POST 1:10 0.44
DMA_CGNO_POST 1:15 0.45
DMA_CGNO_POST 1:20 0.46
DMA_CGNO_POST 1:25 0.47
DMA_CGNO_POST 1:30 0.48
DMA_CGNO_POST 1:35 0.49
DMA_CGNO_POST 1:40 0.50
DMA_CGNO_POST 1:45 0.51
DMA_CGNO_POST 1:50 0.52
DMA_CGNO_POST 1:55 0.54
DMA_CGNO_POST 2:00 0.55
DMA_CGNO_POST 2:05 0.57
DMA_CGNO_POST 2:10 0.58
DMA_CGNO_POST 2:15 0.60
DMA_CGNO_POST 2:20 0.61
DMA_CGNO_POST 2:25 0.64
DMA_CGNO_POST 2:30 0.65
DMA_CGNO_POST 2:35 0.68
DMA_CGNO_POST 2:40 0.70
DMA_CGNO_POST 2:45 0.74
DMA_CGNO_POST 2:50 0.76
DMA_CGNO_POST 2:55 0.81
DMA_CGNO_POST 3:00 0.83
DMA_CGNO_POST 3:05 0.89
DMA_CGNO_POST 3:10 0.93
DMA_CGNO_POST 3:15 1.01
DMA_CGNO_POST 3:20 1.06
DMA_CGNO_POST 3:25 1.17
DMA_CGNO_POST 3:30 1.24
DMA_CGNO_POST 3:35 1.42
DMA_CGNO_POST 3:40 1.54
DMA_CGNO_POST 3:45 1.89
DMA_CGNO_POST 3:50 2.15
DMA_CGNO_POST 3:55 3.15
DMA_CGNO_POST 4:00 4.44
DMA_CGNO_POST 4:05 16.06
DMA_CGNO_POST 4:10 2.53
DMA_CGNO_POST 4:15 1.69
DMA_CGNO_POST 4:20 1.32
DMA_CGNO_POST 4:25 1.11
DMA_CGNO_POST 4:30 0.97
DMA_CGNO_POST 4:35 0.86
DMA_CGNO_POST 4:40 0.78
DMA_CGNO_POST 4:45 0.72
DMA_CGNO_POST 4:50 0.67
DMA_CGNO_POST 4:55 0.62
DMA_CGNO_POST 5:00 0.59
DMA_CGNO_POST 5:05 0.56
DMA_CGNO_POST 5:10 0.53
DMA_CGNO_POST 5:15 0.50
DMA_CGNO_POST 5:20 0.48
DMA_CGNO_POST 5:25 0.46
DMA_CGNO_POST 5:30 0.44
DMA_CGNO_POST 5:35 0.43
DMA_CGNO_POST 5:40 0.41
DMA_CGNO_POST 5:45 0.40
DMA_CGNO_POST 5:50 0.39
DMA_CGNO_POST 5:55 0.38
DMA_CGNO_POST 6:00 0.37
;
DMA_P+Q_POST 1/1/2000 0:00 0
DMA_P+Q_POST 0:10 0.15
DMA_P+Q_POST 0:20 0.15
DMA_P+Q_POST 0:30 0.16
DMA_P+Q_POST 0:40 0.16
DMA_P+Q_POST 0:50 0.17
DMA_P+Q_POST 1:00 0.17
DMA_P+Q_POST 1:10 0.18
DMA_P+Q_POST 1:20 0.18
DMA_P+Q_POST 1:30 0.19
DMA_P+Q_POST 1:40 0.20
DMA_P+Q_POST 1:50 0.21
DMA_P+Q_POST 2:00 0.22
DMA_P+Q_POST 2:10 0.23
DMA_P+Q_POST 2:20 0.24
DMA_P+Q_POST 2:30 0.26
DMA_P+Q_POST 2:40 0.28
DMA_P+Q_POST 2:50 0.31
DMA_P+Q_POST 3:00 0.32
DMA_P+Q_POST 3:10 0.37
DMA_P+Q_POST 3:20 0.40
DMA_P+Q_POST 3:30 0.49
DMA_P+Q_POST 3:40 0.56
DMA_P+Q_POST 3:50 0.82
DMA_P+Q_POST 4:00 1.16
DMA_P+Q_POST 4:10 5.10
DMA_P+Q_POST 4:20 0.66
DMA_P+Q_POST 4:30 0.44
DMA_P+Q_POST 4:40 0.35
DMA_P+Q_POST 4:50 0.29
DMA_P+Q_POST 5:00 0.25
DMA_P+Q_POST 5:10 0.23
DMA_P+Q_POST 5:20 0.20
DMA_P+Q_POST 5:30 0.19
DMA_P+Q_POST 5:40 0.17
DMA_P+Q_POST 5:50 0.16
DMA_P+Q_POST 6:00 0.15
[REPORT]
;;Reporting Options
SUBCATCHMENTS ALL
NODES ALL
LINKS ALL
[TAGS]
[MAP]
DIMENSIONS 191.920 4920.628 1021.827 5718.627
Units None
[COORDINATES]
;;Node X‐Coord Y‐Coord
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
POC‐2_PRE 475.186 4956.495
DMA_CGNO_POST 752.478 5596.104
DMA_P+Q_POST 850.849 5067.555
POC‐2_POST 753.080 4957.093
SURF_B 753.373 5241.877
[VERTICES]
;;Link X‐Coord Y‐Coord
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
[Polygons]
;;Subcatchment X‐Coord Y‐Coord
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
BMP_B 753.080 5467.442
[SYMBOLS]
;;Gage X‐Coord Y‐Coord
;;‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
FAKERAIN 352.458 5673.835
Technical Memorandum
Hope Elementary School 100-Year Storm Detention at POC 2
August 2022
Page 11 Job # 657-01
ATTACHMENT 5
SWMM Summary Report
EPA STORM WATER MANAGEMENT MODEL ‐ VERSION 5.2 (Build 5.2.0)
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Hope ES ‐ Proposed Condition Q100 ‐ POC 2
WARNING 09: time series interval greater than recording interval for Rain Gage FAKERAIN
****************
Analysis Options
****************
Flow Units ............... CFS
Process Models:
Rainfall/Runoff ........ YES
RDII ................... NO
Snowmelt ............... NO
Groundwater ............ NO
Flow Routing ........... YES
Ponding Allowed ........ NO
Water Quality .......... NO
Infiltration Method ...... GREEN_AMPT
Flow Routing Method ...... KINWAVE
Starting Date ............ 01/01/2000 00:00:00
Ending Date .............. 01/02/2000 00:00:00
Antecedent Dry Days ...... 0.0
Report Time Step ......... 00:01:00
Wet Time Step ............ 00:01:00
Dry Time Step ............ 00:01:00
Routing Time Step ........ 60.00 sec
************************** Volume Depth
Runoff Quantity Continuity acre‐feet inches
************************** ‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐
Initial LID Storage ...... 0.013 2.100
Total Precipitation ...... 0.000 0.000
Outfall Runon ............ 0.500 81.594
Evaporation Loss ......... 0.000 0.029
Infiltration Loss ........ 0.027 4.465
Surface Runoff ........... 0.335 54.629
LID Drainage ............. 0.049 8.062
Final Storage ............ 0.101 16.516
Continuity Error (%) ..... ‐0.007
************************** Volume Volume
Flow Routing Continuity acre‐feet 10^6 gal
************************** ‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐
Dry Weather Inflow ....... 0.000 0.000
Wet Weather Inflow ....... 0.384 0.125
Groundwater Inflow ....... 0.000 0.000
RDII Inflow .............. 0.000 0.000
External Inflow .......... 1.026 0.334
External Outflow ......... 1.326 0.432
Flooding Loss ............ 0.000 0.000
Evaporation Loss ......... 0.000 0.000
Exfiltration Loss ........ 0.000 0.000
Initial Stored Volume .... 0.000 0.000
Final Stored Volume ...... 0.083 0.027
Continuity Error (%) ..... 0.050
********************************
Highest Flow Instability Indexes
********************************
All links are stable.
*************************
Routing Time Step Summary
*************************
Minimum Time Step : 60.00 sec
Average Time Step : 60.00 sec
Maximum Time Step : 60.00 sec
% of Time in Steady State : 0.00
Average Iterations per Step : 1.00
% of Steps Not Converging : 0.00
***************************
Subcatchment Runoff Summary
***************************
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Total Total Total Total Imperv Perv Total Total Peak Runoff
Precip Runon Evap Infil Runoff Runoff Runoff Runoff Runoff Coeff
Subcatchment in in in in in in in 10^6 gal CFS
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
BMP_B 0.00 81.59 0.03 4.46 0.00 0.00 62.69 0.13 16.05 0.768
***********************
LID Performance Summary
***********************
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Total Evap Infil Surface Drain Initial Final Continuity
Inflow Loss Loss Outflow Outflow Storage Storage Error
Subcatchment LID Control in in in in in in in %
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
BMP_B BMP_B 81.59 0.03 4.47 54.63 8.06 2.10 16.52 ‐0.01
******************
Node Depth Summary
******************
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Average Maximum Maximum Time of Max Reported
Depth Depth HGL Occurrence Max Depth
Node Type Feet Feet Feet days hr:min Feet
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
POC‐2_PRE OUTFALL 0.00 0.00 0.00 0 00:00 0.00
DMA_CGNO_POST OUTFALL 0.00 0.00 0.00 0 00:00 0.00
DMA_P+Q_POST OUTFALL 0.00 0.00 0.00 0 00:00 0.00
POC‐2_POST OUTFALL 0.00 0.00 0.00 0 00:00 0.00
SURF_B STORAGE 1.27 2.19 219.19 0 04:20 2.19
*******************
Node Inflow Summary
*******************
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Maximum Maximum Lateral Total Flow
Lateral Total Time of Max Inflow Inflow Balance
Inflow Inflow Occurrence Volume Volume Error
Node Type CFS CFS days hr:min 10^6 gal 10^6 gal Percent
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
POC‐2_PRE OUTFALL 6.38 6.38 0 04:11 0.101 0.101 0.000
DMA_CGNO_POST OUTFALL 16.06 16.06 0 04:06 0.163 0.163 0.000
DMA_P+Q_POST OUTFALL 5.10 5.10 0 04:11 0.0704 0.0704 0.000
POC‐2_POST OUTFALL 0.03 1.62 0 04:20 0.0161 0.0979 0.000
SURF_B STORAGE 16.02 16.02 0 04:08 0.109 0.109 0.211
*********************
Node Flooding Summary
*********************
No nodes were flooded.
**********************
Storage Volume Summary
**********************
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Average Avg Evap Exfil Maximum Max Time of Max Maximum
Volume Pcnt Pcnt Pcnt Volume Pcnt Occurrence Outflow
Storage Unit 1000 ft3 Full Loss Loss 1000 ft3 Full days hr:min CFS
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
SURF_B 5.656 38 0 0 10.238 69 0 04:19 1.59
***********************
Outfall Loading Summary
***********************
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Flow Avg Max Total
Freq Flow Flow Volume
Outfall Node Pcnt CFS CFS 10^6 gal
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
POC‐2_PRE 24.93 0.63 6.38 0.101
DMA_CGNO_POST 24.93 1.01 16.06 0.163
DMA_P+Q_POST 24.93 0.44 5.10 0.070
POC‐2_POST 95.42 0.16 1.62 0.098
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
System 42.55 2.23 23.38 0.432
********************
Link Flow Summary
********************
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Maximum Time of Max Maximum Max/ Max/
|Flow| Occurrence |Veloc| Full Full
Link Type CFS days hr:min ft/sec Flow Depth
‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
OUTLET_B DUMMY 1.59 0 04:20
*************************
Conduit Surcharge Summary
*************************
No conduits were surcharged.
Analysis begun on: Tue Aug 9 20:34:50 2022
Analysis ended on: Tue Aug 9 20:34:50 2022
Total elapsed time: < 1 sec