HomeMy WebLinkAboutSUP 07-03; South Coast Materials Quarry; Storm Water Management Plan; 2011-05-06STORM WATER MANAGEMENT PLAN
FOR
SOUTH COA&T MATERIAL
HANSON AGGREGATES QUARRY
(SUP 07-03, SWMP 11-03, DWG 470-5A)
May 6,2011
Prepared/or:
Hanson Aggregates Pacific Southwest, Inc.
P.O. Box 639069
San Diego, CA 92163
RECORD COPY
£
Initial Date
Wayne W. Chang, MS,
Change
Civil Engineering ° Hydrology ° Hydraulics ° Sedimentation
P.O. Box 9496
Rancho Santa Fe, CA 92067
(858) 692-0760
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-TABLE OF CONTENTS -
1.0 Introduction .......................................................................................................................1
1.1 Vicinity Map .....................................................................................................................1
1.2 Project Description ............................................................................................................2
1.3 Site Map ............................................................................................................................3
1.4 Constraints and Opportunities ...........................................................................................3
2.0 Water Quality Environment ..............................................................................................4
2.1 Beneficial Uses .................................................................................................................4
2.1.1 Inland Surface Waters .......................................................................................................5
2.1.2 Groundwater .....................................................................................................................5
3.0 Pollutants and Conditions of Concern ..............................................................................5
3.1 Pollutants from Project Area .............................................................................................5
3.2 Pollutants of Concern in Receiving Waters ......................................................................6
4.0 Permanent Storm Water Best Management Practices ......................................................7
4.1 Standard Site Design BMPs ..............................................................................................7
4.2 Source Control BMPs .......................................................................................................8
4.3 Low Impact Development Site Design BMPs/Treatment Control BMPs (TCBMP) .......9
4.4 Hydromodification Exemption .......................................................................................10
5.0 Storm Water BMP Maintenance .....................................................................................11
6.0 Summary/Conclusions ....................................................................................................12
7.0 Certification ....................................................................................................................13
8.0 Owner’s Certification......................................................................................................13
Grading Plan Drawings
Storm Water Standards Questionnaire, E-34
2007 303(d) List
Existing and Proposed Condition Rational Method Work Maps
APPENDIX
A. Low Impact Development Extended Detention Basin Design
MAP POCKET
BMP Map
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1.0 INTRODUCTION
This Storm Water Management Plan (SWMP) addresses water quality requirements
associated with reclamation of Hanson Aggregates Pacific Southwest, Inc.’s (Hanson) quarry
(Hanson Aggregates Quarry) located within the cities of Carlsbad and Oceanside. A
preliminary SWMP was prepared and approved during the entitlement process. This SWMP
is for the reclamation plan’s final engineering and follows the criteria outlined in the City of
Carlsbad’s January 14, 2011, Standard Urban Storm Water Management Plan (SUSMP).
The January 14 SUSMP contains additional requirements that were not present when the
preliminary SWMP was prepared. The additional requirements are addressed in this final
SWMP.
According to the City’s Storm Water Standards Questionnaire E-34 (attached following this
report text), the development is in the “More than 1-acre of disturbance” priority
development project category. The project is not increasing the impervious area (the
impervious area will decrease) and is therefore not increasing unmitigated peak flow rates, so
it is not subject to hydromodification criteria. The SUSMP outlines the SWMP objectives,
which are to identify site opportunities and constraints, identify pollutants and conditions of
concern, follow low impact development design objectives, describe best management
practices (BMPs), and outline maintenance requirements. BMPs will be utilized to the
maximum extent practicable to provide a long-term solution for addressing runoff water
quality. BMPs were selected that meet the current regulations and also fit within the entitled
project.
1.1 Vicinity Map
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1.2 Project Description
The reclamation site is located south of Haymar Drive and west of College Boulevard in the
cities of Carlsbad and Oceanside, California (see Vicinity Map). The mining site historically
contained a quarry and associated operations. The easterly portion of the overall mining site
has been reclaimed and developed with retail uses (Quarry Creek Shopping Center). Hanson
is now preparing to reclaim the remainder of the site, which consists of Phases 2B, 3, and 4.
This report has been prepared for reclamation of these remaining phases based on the final
engineering plans. The phases encompass a portion of the project site entirely within the city
of Carlsbad (100.13 acres) as well as a small northeastern portion of the project site (4.10
acres) within the city of Oceanside.
The quarry operations are complete. The past mining has resulted in cut slopes (2:1 and
steeper) and large, gently sloping earthen pads. The cut slopes are present along portions of
the north, south, and east mining limits. The south half of the easterly project perimeter
contains a Keystone retaining wall that was constructed for the adjacent off-site shopping
center. The mined areas between the cut slopes are now large, rough-graded earthen pads.
The area west of the mining footprint is mostly undisturbed.
Buena Vista Creek enters the eastern portion of the project site at El Salto Falls, and flows in
a westerly direction through the middle of the project site. Buena Vista Creek has been
channelized through the mining area and contains three vehicular crossings. Immediately
downstream of the mining area, the creek broadens into a natural floodplain. Surface runoff
within the site and tributary areas flows into Buena Vista Creek. There are three existing
storm drain systems that solely capture off-site runoff and outfall onto the site. One is along
the northerly boundary and the other two are along the southerly portion of the easterly
boundary (near the westerly terminus of Marron Road). The project will extend the storm
drains and outfalls through the site to Buena Vista Creek to avoid commingling with on-site
runoff. Even though the off-site runoff will not be commingled with on-site runoff, the City
of Carlsbad is requiring treatment of the off-site runoff because the pre-project natural
surfaces provide some filtering of the off-site runoff. In order to provide treatment, a low
flow pipe will be installed in each of the proposed storm drains to direct the off-site low flow
into bio-filter swales for treatment.
The only recent activity at the project site is material (concrete, etc.) recycling. The recycling
operation is located within the southwesterly pad area. The project site also currently
contains several bio-remediation piles. These are contaminated dirt piles stored on-site for
remediation and monitored by Brown and Caldwell. The piles will either reach a non-detect
level and be used by the on-site grading, or be transported to an appropriate disposal site in
accordance will all applicable regulations.
The project reclamation will include rechannelization of Buena Vista Creek, which flows in a
westerly direction and bisects the project site. The creek currently does not contain the 100-
year floodplain and is hydraulically steep, which can lead to erosion. The rechannelization
will include widening of the creek channel and reducing the gradient by constructing seven
drop structures of varying height and at irregular intervals along the channel. This will create
a channel that is stable during a 100-year storm event. The reclamation also includes the
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creation of large, relatively level pads north and south of the creek. The reclamation does not
propose development of the site other than the channelization, pad grading with associated
drainage improvements, and landscaping and irrigation. The reclamation will result in fewer
impervious surfaces since the structures and majority of the paving will be removed. As a
result the project will reduce the flow volumes and rates leaving the site.
1.3 Site Map
See the Grading Plan drawings following this report text for the site map. This plan is the
design approved during the final engineering process.
1.4 Constraints and Opportunities
The site previously supported quarry operations that resulted in ground disturbance over an
approximately 40 acre area in Carlsbad. The proposed reclamation grading will not disturb
beyond the areas previously disturbed by the quarry. As a result, most of the existing on-site
habitat will not be impacted by the project.
The reclamation will not create impervious surfaces other than minor impervious surfaces
associated with the proposed drainage facilities (e.g., concrete ditch, concrete cleanout, etc.).
Most of the existing impervious surfaces (buildings, foundations, paving, etc.) will be
removed by the reclamation plan. The only impervious surface of any significance that will
remain is a portion of the existing asphalt access road from Haymar Drive. This is needed to
provide access to the site down a steep grade.
Buena Vista Creek flows in a westerly direction through the site. Under current conditions,
the creek is conveyed in a narrow channel with varying levels of un-engineered protection on
the banks. The majority of the existing channel is not able to convey the 100-year flows
including a segment above El Salto Falls. The existing channel is also hydraulically steep and
subject to erosion during high flows.
The proposed project will increase the channel capacity by widening the channel
significantly and also constructing a levee above El Salto Falls. Seven rock drop structures
will flatten the channel profile to reduce flow velocities. The result will be a channel that is
able to convey the 100-year storm flows, adequately protected against erosion, and capable
of supporting a much greater amount of habitat.
The primary pollutant generated by the completed reclamation will be sediment. A series of
extended detention (desiltation) basins have been designed in accordance with low impact
development guidelines to capture sediment from the site. The basins have been designed in
accordance with the City of Carlsbad’s latest SUSMP dated January 14, 2011.
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2.0 WATER QUALITY ENVIRONMENT
2.1 Beneficial Uses
The beneficial uses for the hydrologic unit are included in Tables 1 and 2. These tables were
obtained from the April 25, 2007 amended Water Quality Control Plan for the San Diego
Basin (9). The following contains definitions of the beneficial uses in the tables:
MUN – Municipal and Domestic Supply: Includes uses of water for community,
military, or individual water supply systems including, but not limited to, drinking
water supply.
AGR – Agricultural Supply (AGR): Includes uses of water for farming,
horticulture, or ranching including, but not limited to, irrigation, stock watering, or
support of vegetation for range grazing.
IND – Industrial Services Supply: Includes uses of water for industrial activities
that do not depend primarily on water quality including, but not limited to, mining,
cooling water supply, hydraulic conveyance, gravel washing, fire protection, or oil
well re-pressurization.
REC1 – Contact Recreation: Includes uses of water for recreational activities
involving body contact with water, where ingestion of water is reasonably possible.
These uses include, but are not limited to, swimming, wading, water-skiing, skin and
SCUBA diving, surfing, white water activities, fishing, or use of natural hot springs.
REC2 – Non-Contact Recreation: Includes the uses of water for recreational
involving proximity to water, but not normally involving body contact with water,
where ingestion of water is reasonably possible. These uses include, but are not
limited to, picnicking, sunbathing, hiking, camping, boating, tide pool and marine life
study, hunting, sightseeing, or aesthetic enjoyment in conjunction with the above
activities.
WARM – Warm Freshwater Habitat: Includes uses of water that support warm
water ecosystems including, but not limited to, preservation or enhancement of
aquatic habitats, vegetation, fish or wildlife, including invertebrates.
WILD – Wildlife Habitat: Includes uses of water that support terrestrial ecosystems
including, but not limited to, preservation and enhancement of terrestrial habitats,
vegetation, wildlife, (e.g., mammals, birds, reptiles, amphibians, invertebrates), or
wildlife water and food sources.
RARE – Rare: Bodies of water where the protection of a threatened or endangered
species depends on the water either directly, or to support its habitat.
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2.1.1 Inland Surface Waters
Inland surface waters for the Buena Vista Creek Hydrologic Area have the beneficial uses
shown in Table 1:
Table 1. Beneficial Uses for Inland Surface Waters
Hydrologic
Unit
Code Mun Agr Ind Proc Gwr Frsh Pow Rec1 Rec2 Biol Warm Cold Wild Rare Spwn 904.21 + ● ● ● ● ● ● ●
+ Exempted by the Regional Board from the municipal used designation.
● Existing Beneficial Use
2.1.2 Groundwater
Groundwater beneficial uses for the El Salto Hydrologic Subarea are shown in Table 2:
Table 2. Beneficial Uses for Groundwater
Hydrologic
Unit
Code
Mun Agr Ind Proc Frsh Gwr 904.21 ● ●
● Existing Beneficial Use
Potential Beneficial Use
3.0 POLLUTANTS AND CONDITIONS OF CONCERN
3.1 Pollutants from Project Area
The project is located within the El Salto Hydrologic Subarea (904.21) of the Buena Vista
Creek Hydrologic Area (904.20), which is within the Carlsbad Hydrologic Unit (904.00).
The total drainage area of the hydrologic unit is approximately 210 square miles. Runoff
from the hydrologic area ultimately drains to Buena Vista Creek, which bisects the project
site. All of the project runoff will enter Buena Vista Creek. The project site represents less
than one percent of the Buena Vista Creek watershed.
The following table lists pollutants of concern that can potentially exist at proposed priority
development project sites. The pollutants are from the city of Carlsbad’s SUSMP. The
project does not fall within any of the priority development project categories in the table.
However, the project is a priority development project because it results in disturbance of 1
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acre or more of land and is considered a pollutant-generating development project since it
will introduce new landscaping areas that require some fertilization. The project merely
proposes grading and landscaping to stabilize Buena Vista Creek, and reclaim the project site
from its mined condition. The project does not propose any paving or priority project end
uses other than a stable graded site.
The primary pollutant expected from the reclaimed project site will be sediment. Nutrients
are a lesser pollutant, but can also be generated by the limited amount of fertilizers used for
landscaping. According to the landscape architect, some fertilizers can be present in the
initial hydroseeding and very limited fertilization could be applied after the initial planting
and seeding.
Priority
Project
Categories
Sediments
Nutrients
Heavy
Metals
Organic
Compounds
Trash
&
Debris
Oxygen
Demanding
Substances
Oil
&
Grease
Bacteria
&
Viruses
Pesticides
Detached
Residential
Development
X
X
X
X
X
X
X
Attached
Residential
Development
X
X
X
P(1)
P(2)
P
X
Commercial
Development
> one acre
P(1)
P(1)
X
P(2)
X
P(5)
X
P(3)
P(5)
Heavy
Industry X
X X X X X
Automotive
Repair Shops X X(4)(5) X X
Restaurants X X X X P(1)
Hillside
Development
>5,000 ft2
X
X
X
X
X
X
Parking Lots P(1) P(1) X X P(1) X P(1)
Retail
Gasoline
Outlets
X X X X X
Streets,
Highways &
Freeways
X
P(1)
X
X(4)
X
P(5)
X
X
P(1)
X = Anticipated
P = Potential
(1) A potential pollutant if landscaping exists on-site
(2) A potential pollutant if the project includes uncovered parking areas
(3) A potential pollutant if land use involves food or animal waste products
(4) Including petroleum hydrocarbons
(5) Including solvents
3.2 Pollutants of Concern in Receiving Waters
According to the June 28, 2007 303(d) list approved by the US Environmental Protection
Agency (attached after this report text), the receiving water body closest to the project
vicinity, Buena Vista Creek, is 303(d) listed for sediment toxicity, but is not subject to total
maximum daily loads.
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The project does not fall within the priority development project categories in the table in
Section 3.1. Therefore, the project does not generate pollutants of concern associated with
priority development project categories. Nonetheless, BMPs have been incorporated into the
site design to address the primary pollutant (sediment) generated at the site. The BMPs have
been designed in accordance with the latest City of Carlsbad SUSMP dated January 14, 2011.
4.0 PERMANENT STORM WATER BEST MANAGEMENT PRACTICES
To address water quality for the project, best management practices (BMPs) will be
implemented. The following discusses the Standard Site Design, Source Control, and Low
Impact Development design BMPs for the project.
4.1 Standard Site Design BMPs
The City of Carlsbad’s standard objectives are required for all projects. The project will
accomplish these goals through the following BMPs, which are from the Carlsbad SUSMP:
Standard Stormwater Requirements
Minimize Impervious Surfaces. The project does not propose any significant impervious
surfaces. The only impervious surfaces will be small areas associated with drainage facilities
(ditches, cleanouts, etc.). Most of the existing impervious surfaces (paving and buildings)
will be removed during the reclamation grading.
Disconnect Discharges. The majority of the storm runoff generated from the project site will
occur as sheet flow over the natural ground surface. The project will not construct structures
or paving that require disconnected discharges.
Conserve Natural Areas. Only the area previously disturbed by the quarry will be graded.
The remaining natural areas within the property boundary will remain natural.
Stenciling Inlets and Signage. All proposed inlets shall be stenciled with “No Dumping!
Flows to Bay” or approved similar. The project does not contain public access points along
Buena Vista Creek, so signage is not necessary.
Landscape Design. A landscape plan will be prepared that uses drought-tolerant species in
accordance with the City’s landscape manual. Native trees and shrubs will be preserved over
the majority of the parcel in order to maximize canopy interception and promote water
conservation. The project will only use water as needed to support the landscaping.
Water Efficient Irrigation. The irrigation systems will be designed to each landscaped areas
water requirements to avoid over irrigation. Rain shutoff devices will be used, if required, to
prevent irrigation after rain events.
Protect Slopes And Channels. The grading design will include slope terraces in accordance
with agency guidelines. The design will prevent runoff from flowing uncontrolled over the
8
tops of manufactured slopes. The proposed slopes will be landscaped. Riprap energy
dissipaters will be used at storm drain outfalls. The Buena Vista Creek channel is being
designed to control and handle erosive velocities.
Trash Receptacles. The completed reclamation grading will not support uses that require
trash receptacles.
Material Storage Areas. The completed project will not create outdoor material storage areas.
4.2 Source Control BMPs
Source control BMPs will consist of measures to prevent polluted runoff. After the
reclamation grading is complete, the site will be vacant and not support any uses. The
following addresses the source control BMPs from the Carlsbad SUSMP (Appendix 1):
Potential Source
of Runoff Pollutants
Permanent Source
Control BMPs
Operational Source
Control BMPs
On-site storm drain
inlets
Mark all inlets with “No
Dumping! Flows to Bay” or
similar.
Provide stormwater pollution
information to new site owners,
lessees, or operators.
See applicable operational
BMPs in Fact sheet SC-44,
“Drainage System
Maintenance,” in the CASQA
Stormwater Quality Handbook
(Industrial and Commercial) at
www.cabmphandbooks.com)
Landscape/Outdoor
Pesticide Use
Final landscape plans will
accomplish all of the
following.
Preserve existing native trees,
shrubs, and ground cover to
the maximum extent possible.
Design landscaping to
minimize irrigation and
runoff, to promote surface
infiltration where
appropriate, and to minimize
the use of fertilizers and
pesticides that can contribute
to stormwater pollution.
Where landscaped areas can
retain or detain stormwater,
specify plants that are
Maintain landscaping using
minimum or no pesticides.
See applicable operational BMPs in Fact Sheet SC-41,
"Building and Grounds
Maintenance," in the CASQA Stormwater Quality Handbooks at
www.cabmphandbooks.com
Provide Integrated Pest
Management information to new owners, lessees, and operators.
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tolerant of saturated soil
conditions.
Consider using pest-resistant
plants, especially adjacent to
hardscape.
To ensure successful
establishment, select plants
appropriate to site soils,
slopes, climate, sun, wind,
rain, land use, air movement,
ecological consistency, and
plant interactions.
4.3 Low Impact Development Site Design BMPs/Treatment Control BMPs
(TCBMP)
The preliminary SWMP approved during the entitlement process was based on the
regulations at the time of preparation in February 2010. Since then, the City of Carlsbad
updated the SUSMP in March 24, 2010 and January 14, 2011. For the final engineering
design, the Low Impact Development (LID) BMPs have been updated and sized to meet the
January 14, 2011 LID requirements (see Appendix A for the calculations). Treatment Control
BMPs have also been designed and included in Appendix A. The integrated LID outlines
four strategies:
1. Optimize the site layout by preserving natural drainage features and designing
buildings and circulation to minimize the amount of roofs and paving.
2. Use pervious surfaces such as turf, gravel, or pervious pavement—or use surfaces that
retain rainfall. All drainage from these surfaces is considered to be “self-retained”.
3. Disperse runoff from impervious surfaces on to adjacent pervious surfaces (e.g.,
direct a roof downspout to disperse runoff onto a lawn).
4. Drain impervious surfaces to engineered Integrated Management Practices (IMPs),
such as bioretention facilities, planter boxes, cisterns, or dry wells. IMPs infiltrate
runoff to groundwater and/or percolate runoff through engineered soil and allow it to
drain away slowly.
The project design is in compliance with these strategies. The site layout preserves the
alignment of the Buena Vista Creek channel as well as the current drainage patterns outside
the grading area. The graded area will generally sheet flow along naturally-lined surfaces.
The project does not propose buildings or roadways. Nearly all of the proposed surfaces will
be pervious earthen surfaces or covered with landscaping.
Since the primary pollutant generated from the project site will be sediment, the most
appropriate BMP will be extended (“dry”) detention basins, i.e., desiltation basins, which are
10
defined in the Carlsbad SUSMP as an alternative to integrated LID design. According to
Table 2-3 in the SUSMP, these basins also have a high effectiveness for treating nutrients,
which is a secondary pollutant generated by the project. The SUSMP requires that the basin
volume be based on the product of the County of San Diego’s 85th Percentile Isopluvial Map
(0.65 inches), the LID weighted runoff factor (0.10 for pervious surfaces), and the tributary
area. The volume of each of the three proposed basins was sized using these criteria (see
Appendix A). In accordance with the SUSMP, additional design considerations and details
were obtained from Fact Sheet TC-22, Extended Detention Basins from the CASQA
California Stormwater Best Management Practice Handbooks. In particular, the storage
depth below the outflow riser is approximately 4 feet and the basin side slopes are 3:1
maximum.
4.4 Hydromodification Exemption
In addition to satisfying LID and numeric requirements, priority development projects can be
subject to hydromodification controls. The HMP Applicability Determination from Figure 2-
1 of the SUSMP is used to make the determination. The following steps from the table were
followed and resulted in a determination that the project is not subject to hydromodification:
Is Project a Priority Development Project?
The attached Storm Water Standards Questionnaire E-34 shows that the project is a
Priority Development Project.
Proper Energy Dissipation Provided?
The proposed storm drains and outlets are being designed with riprap energy
dissipation in accordance with standard engineering practice.
Does Project Increase Impervious Area?
The project will not construct paving or structures, so it will not increase the
impervious area. The project will remove existing paving and structures resulting in a
net decrease in impervious area.
Does Project Increase Unmitigated Peak Flows to Any Outlet Location.
Storm runoff from the project flows into Buena Vista Creek from the north and south
under pre- and post-project conditions. The general flow patterns will be unchanged
and the impervious area will be reduced by the project. Therefore, the project will not
increase the unmitigated peak flows outletting into the creek. In addition, the creek
channel will be stabilized by the project, which will reduce the potential for erosion in
the creek.
Pre- and post-project 2- and 10-year hydrologic analyses have been performed to
verify that this condition is being met. Under post-project (proposed) conditions,
runoff will outlet into Buena Vista Creek at four locations including three storm drain
outlets along the north creek bank and one outlet along the south creek bank. Pre-
project (existing condition) hydrologic analyses were performed to determine the
flows at similar outlet locations. The analyses are included in the April 7, 2011,
Drainage Report for South Coast Materials Quarry, by Chang Consultants and are
11
summarized in the table below. The results show that the project will not increase the
2- or 10-year flow rates from the site. The primary reason is because the project will
replace the majority of the impervious surfaces at the site with pervious surfaces. The
Existing and Proposed Condition Rational Work Maps from the drainage report are
included after this report text.
Drainage
Basin
Exist. Cond.
Tributary
Area, Ac
Prop. Cond.
Tributary
Area, Ac
Exist. Cond.
2-Year Flow,
cfs
Prop. Cond.
2-Year Flow,
cfs
Exist. Cond.
10-Year Flow,
cfs
Prop. Cond.
10-Year Flow,
cfs
100 73.28 72.39 91 91 134 134
200 13.70 16.17 16 14 23 21
300 9.74 8.16 9 6 13 8
400 56.75 56.75 39 38 56 55
Summary of 2- and 10-Year Flow Rates
From these steps, Figure 2-1 shows that the project is HMP exempt.
5.0 STORM WATER BMP MAINTENANCE
Hanson, as property owner, will be responsible for funding and implementing the operations
and maintenance of the project BMPs. Provisions will be made to transfer operations and
maintenance to the new owner in the event of a change in ownership. This primarily includes
maintenance of the landscaping and extended detention basins. The following describes the
specific BMP maintenance.
Landscaping
The landscaping and channel habitat will be designed by The Lightfoot Planning Group and
Helix Environmental Planning, Inc. Vegetation will be initially planted in the Buena Vista
Creek channel and in the upland slopes. The creek vegetation will be designed for minimal, if
any, maintenance. It is anticipated that the resource agencies will require a multi-year
monitoring period to ensure that the creek habitat is meeting performance standards.
Maintenance and monitoring will be established in accordance with the resource agency
requirements.
Similarly, the upland vegetation will be designed for minimal maintenance. Maintenance and
replanting will be performed by landscaping personnel. Maintenance will primarily consist of
replanting, as needed.
Efficient Irrigation
The landscaping personnel shall inspect and maintain the irrigation system on a regular basis.
This will occur during the routine maintenance activities. All valves, heads, shutoff devices,
lines, etc. shall be kept in a properly functioning condition. Any defective parts shall be
replaced immediately. The irrigation system shall be adjusted to prevent excessive runoff
from landscape areas. The irrigation schedule shall be adjusted based on seasonal needs.
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Extended Detention (Desiltation + Infiltration) Basins (see Appendix A for Sizing
Calculations)
The extended detention basins shall be inspected for accumulated sediment and debris at the
beginning and end of each rainy season. The sediment and debris shall be removed prior to
and following the rainy season. Inspections and removal shall also occur following any
precipitation events exceeding a 10-year magnitude. During each inspection, the outlet riser,
gravel cone, and anti-vortex plate shall also be inspected and maintained, as needed.
Inlet Stenciling
The legibility of markers and signs shall be maintained by Hanson. Any stenciling shall be
inspected at the beginning and end of each rainy season and repaired or replaced, as needed.
Hazardous Wastes
Suspected hazardous wastes will be analyzed to determine disposal options. Hazardous
materials are not expected to be generated on-site (except for the soil stockpiles currently
undergoing remediation); however, if discovered, hazardous materials will be handled and
disposed of according to local, state, and federal regulations. A solid or liquid waste is
considered a hazardous waste if it exceeds the criteria listed in the California Code of Federal
Regulations, Title 22, Article 11 (State of California, 1985).
6.0 SUMMARY/CONCLUSIONS
This final SWMP has been prepared in accordance with the City of Carlsbad’s January 14,
2011, Standard Urban Storm Water Management Plan, and has evaluated and addressed
potential pollutants associated with the Hanson Aggregates Quarry reclamation project and
its effects on water quality. This SWMP has been based on the final engineering plans. A
summary of the facts and findings associated with the reclamation project and the measures
addressed by this SWMP are as follows:
The beneficial uses for the receiving waters have been identified. None of these
beneficial uses will be impaired or diminished due to the construction and operation
of the project site.
The project will not significantly alter drainage patterns or flow rates from the project
site. The project will not add impervious surfaces and will maintain storm runoff into
Buena Vista Creek. In fact, the project will remove some existing structures and
paving, which will slightly reduce the project site imperviousness.
A Storm Water Pollution Prevention Plan for construction activities has been
prepared to address construction-related water quality objectives.
Permanent BMPs will be incorporated into the reclamation project in the form of site
design, source control, and LID treatment control.
The proposed BMPs address mitigation measures to protect water quality and
beneficial uses to the maximum extent practicable.
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Hanson Aggregates Pacific Southwest, Inc. will be responsible for BMP maintenance
and operations.
7.0 CERTIFICATION
The selection, sizing, and preliminary design of stormwater treatment and other control
measures in this plan meet the requirements of Regional Water Quality Control Board Order
R9-2007-0001 and subsequent amendments.
May 6, 2011
Wayne W. Chang, RCE 46548 Date
8.0 OWNER’S CERTIFICATION
I certify that, as the owner’s representative of the property described herein, I have read and
understand the requirements of this Storm Water Management Plan (SWMP) and that I am
responsible for ensuring that all storm water treatment measures described within said
SWMP will be properly implemented, monitored, and maintained.
May 6, 2011
Marvin E. Howell Date
E-34 Page 1 of 3 REV 1/14/11
Development Services
Land Development Engineering
1635 Faraday Avenue
760-602-2750
www.carlsbadca.gov
STORM WATER
STANDARDS
QUESTIONNAIRE
E-34
INSTRUCTIONS:
To address post-development pollutants that may be generated from development projects, the City requires that new
development and significant redevelopment priority projects incorporate Permanent Storm Water Best Management
Practices (BMP‟s) into the project design per the City‟s Standard Urban Stormwater Management Plan (SUSMP). To
view the SUSMP, refer to the Engineering Standards (Volume 4, Chapter 2) at www.carlsbadca.gov/standards.
Initially this questionnaire must be completed by the applicant in advance of submitting for a development application
(subdivision, discretionary permits and/or construction permits). The results of the questionnaire determine the level of
storm water standards that must be applied to a proposed development or redevelopment project. Depending on the
outcome, your project will either be subject to „Standard Stormwater Requirements‟ or be subject to additional criteria
called „Priority Development Project Requirements‟. Many aspects of project site design are dependent upon the
storm water standards applied to a project.
Your responses to the questionnaire represent an initial assessment of the proposed project conditions and impacts.
City staff has responsibility for making the final assessment after submission of the development application. If staff
determines that the questionnaire was incorrectly filled out and is subject to more stringent storm water standards than
initially assessed by you, this will result in the return of the development application as incomplete. In this case, please
make the changes to the questionnaire and resubmit to the City.
If you are unsure about the meaning of a question or need help in determining how to respond to one or more of the
questions, please seek assistance from Land Development Engineering staff.
A separate completed and signed questionnaire must be submitted for each new development application submission.
Only one completed and signed questionnaire is required when multiple development applications for the same project
are submitted concurrently. In addition to this questionnaire, you must also complete, sign and submit a Project Threat
Assessment Form with construction permits for the project.
Please start by completing Section 1 and follow the instructions. When completed, sign the form at the end and submit
this with your application to the city.
SECTION 1 NEW DEVELOPMENT
Does your project meet one or more of the following criteria: YES NO
1. Housing subdivisions of 10 or more dwelling units. Examples: single family homes, multi-family homes,
condominium and apartments
2. Commercial – greater than 1-acre. Any development other than heavy industry or residential. Examples: hospitals;
laboratories and other medical facilities; educational institutions; recreational facilities; municipal facilities; commercial
nurseries; multi-apartment buildings; car wash facilities; mini-malls and other business complexes; shopping malls;
hotels; office buildings; public warehouses; automotive dealerships; airfields; and other light industrial facilities.
3. Heavy Industrial / Industry- greater than 1 acre. Examples: manufacturing plants, food processing plants, metal
working facilities, printing plants, and fleet storage areas (bus, truck, etc.).
4. Automotive repair shop. A facility categorized in any one of Standard Industrial Classification (SIC) codes 5013,
5014, 5541, 7532-7534, and 7536-7539
5. Restaurants. Any facility that sells prepared foods and drinks for consumption, including stationary lunch counters
and refreshment stands selling prepared foods and drinks for immediate consumption (SIC code 5812), where the
land area for development is greater than 5,000 square feet. Restaurants where land development is less than 5,000
square feet shall meet all SUSMP requirements except for structural treatment BMP and numeric sizing criteria
requirements and hydromodification requirements.
E-34 Page 2 of 3 REV 1/14/11
Development Services
Land Development Engineering
1635 Faraday Avenue
760-602-2750
www.carlsbadca.gov
STORM WATER
STANDARDS
QUESTIONNAIRE
E-34
6. Hillside development. Any development that creates more than 5,000 square feet of impervious surface and is
located in an area with known erosive soil conditions, where the development will grade on any natural slope that is
twenty-five percent (25%) or greater.
7. Environmentally Sensitive Area (ESA)1. All development located within or directly adjacent2 to or discharging
directly3 to an ESA (where discharges from the development or redevelopment will enter receiving waters within the
ESA), which either creates 2,500 square feet or more of impervious surface on a proposed project site or increases
the area of imperviousness of a proposed project site 10% or more of its naturally occurring condition.
8. Parking lot. Area of 5,000 square feet or more, or with 15 or more parking spaces, and potentially exposed to urban
runoff
9. Streets, roads, highways, and freeways. Any paved surface that is 5,000 square feet or greater used for the
transportation of automobiles, trucks, motorcycles, and other vehicles
10. Retail Gasoline Outlets. Serving more than 100 vehicles per day and greater than 5,000 square feet
11. Coastal Development Zone. Any project located within 200 feet of the Pacific Ocean and (1) creates more than
2500 square feet of impervious surface or (2) increases impervious surface on property by more than 10%.
12. More than 1-acre of disturbance. Project results in the disturbance of 1-acre or more of land and is considered a
Pollutant-generating Development Project4.
1 Environmentally Sensitive Areas include but are not limited to all Clean Water Act Section 303(d) impaired water bodies; areas designated as Areas of Special Biological Significance by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); water bodies
designated with the RARE beneficial use by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments);
areas designated as preserves or their equivalent under the Multi Species Conservation Program within the Cities and County of San Diego; and any other equivalent
environmentally sensitive areas which have been identified by the Copermittees.
2 “Directly adjacent” means situated within 200 feet of the Environmentally Sensitive Area.
3 “Discharging directly to” means outflow from a drainage conveyance system that is composed entirely of flows from the subject development or redevelopment site, and
not commingled with flow from adjacent lands.
4 Pollutant-generating Development Projects are those projects that generate pollutants at levels greater than background levels. In general, these include all projects
that contribute to an exceedance to an impaired water body or which create new impervious surfaces greater than 5000 square feet and/or introduce new landscaping
areas that require routine use of fertilizers and pesticides. In most cases linear pathway projects that are for infrequent vehicle use, such as emergency or maintenance
access, or for pedestrian or bicycle use, are not considered Pollutant-generating Development Projects if they are built with pervious surfaces or if they sheet flow to
surrounding pervious surfaces.
INSTRUCTIONS::
Section 1 Results:
If you answered YES to ANY of the questions above, your project is subject to Priority Development Project requirements. Skip Section 2 and
please proceed to Section 3. Check the “meets PRIORITY DEVELOPMENT PROJECT requirements” box in Section 3. Additional storm water
requirements will apply per the SUSMP. If you answered NO to ALL of the questions above, then please proceed to Section 2 and follow the instructions.
CITY OF
CARLSBAD
STORM WATER
STANDARDS
QUESTIONNAIRE
E-34
Development Services
Land Development Engineering
1635 Faraday Avenue
760-602-2750
www.carlsbadca.gov
INSTRUCTIONS: Complete the questions below regarding your project YES NO
1. Project results in the disturbance of 1-acre or more of land and is considered a Pollutant-generating Development
Project'?
INSTRUCTIONS: If you answered NO, please proceed to question 2.
If you answered YES, then you ARE a significant redevelopment and you ARE subject to PRIORITY DEVELOPMENT PROJECT
requirements. Please check the "meets PRIORITY DEVELOPMENT PROJECT requirements" box in Section 3 below.
2. Is the project redeveloping an existing priority project type? (Priority projects are defined in Section 1)
INSTRUCTIONS: If you answered YES, please proceed to question 3.
If you answered NO, then you ARE NOT a significant redevelopment and your project is subject to STANDARD STORMWATER
REQUIREMENTS. Please check the "does not meet PDP requirements" box in Section 3 below.
3. Is the work limited to trenching and resurfacing associated with utility work; resurfacing and reconfiguring surface
parking lots and existing roadways; new sidewalk; bike lane on existing road and/or routine maintenance of damaged
pavement such as pothole repair? Resurfacing/reconfiguring parking lots is where the work does not expose underlying soil
during construction.
INSTRUCTIONS: If you answered NO, then proceed to question 4.
If you answered YES, then you ARE NOT a significant redevelopment and your project is subject to STANDARD STORMWATER
REQUIREMENTS. Please check the "does not meet PDP requirements" box in Section 3 below.
4. Will your redevelopment project create, replace, or add at least 5,000 square feet of impervious surfaces on existing
developed property or will your project be located within 200 feet of the Pacific Ocean and (1) create 2500 square feet or
more of impervious surface or (2) increases impervious surface on the property by more than 10%? Replacement of
existing impervious surfaces includes any activity that is not part of routine maintenance where impervious material(s) are
removed, exposing underlying soil during construction.
INSTRUCTIONS: If you answered YES, you ARE a significant redevelopment, and you ARE subject to PRIORITY DEVELOPMENT
PROJECT requirements. Please check the "meets PRIORITY DEVELOPMENT PROJECT requirements" box in Section 3 below. Review
SUSMP to find out if SUSMP requirements apply to your project envelope or the entire project site.
If you answered NO, then you ARE NOT a significant redevelopment and your project is subject to STANDARD STORMWATER
REQUIREMENTS. Please check the "does not meet PDP requirements" box in Section 3 below.
*for definition see Footnote 4 on page 2
My project meets PRIORITY DEVELOPMENT PROJECT (PDP) requirements and must comply with additional stormwater criteria
per the SUSMP and I understand I must prepare a Storm Water Management Plan for submittal at time of application. I understand
flow control (hydromodification) requirements may apply to my project. Refer to SUSMP for details.
My project does not meet PDP requirements and must only comply with STANDARD STORMWATER REQUIREMENTS per the
SUSMP. As part of these requirements, I will incorporate low impact development strategies throughout my project.
Applicant Information and Signature Box This Box for City Use Only
Address: 3701 Haymar Drive
Carlsbad, CA 92008
Applicant Name:
Wayne W. Chang
^fflfiW Signature//
'nMM iM^ts-
Assessor's Parcel Number(s):
167-040-21, 168-011-20
Applicant Title:
Principal
Date:
February 15,2011
City Concurrence:NO
By:
Projec,,D
E-34 Page 3 of 3 REV 1/14/11
REGIONTYPE NAMEPOLLUTANT/STRESSORCALWATER WATERSHED ESTIMATED SIZE AFFECTEDPOTENTIAL SOURCES2006 CWA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTSCOMPLETIONPROPOSED OR USEPA APPROVED TMDL COMPLETIONUSEPA APPROVAL DATE: JUNE 28, 2007(Those requiring TMDLS (A), being addressed by USEPA approved TMDLS (B), and being addressed by actions other than TMDLs (C))*TMDL REQUIREMENT STATUS*Buena Creek9R90432000DDT4.82019 MilesASource UnknownNitrate and Nitrite4.82019 MilesASource UnknownPhosphate4.82019 MilesASource Unknown Buena Vista Creek9R90421000Sediment Toxicity112019 MilesASource Unknown Buena Vista Lagoon9E90421000Indicator bacteria2022008AcresANonpoint/Point SourceNutrients2022019Estimated size of impairment is 150 acres located in upper portion of lagoon.AcresANonpoint/Point SourceSedimentation/Siltation2022019AcresANonpoint/Point Source Chollas Creek9R90822000Copper3.52004 MilesANonpoint/Point SourceDiazinon3.52003 MilesBNonpoint/Point SourceIndicator bacteria3.52005 MilesANonpoint/Point SourcePage 273 of 299
APPENDIX A
LOW IMPACT DEVELOPMENT
EXTENDED DETENTION BASIN DESIGN
1
SUMMARY
Since the primary pollutant generated from the project site will be sediment, the most
appropriate BMP will be extended (“dry”) detention basins, i.e., desiltation basins, which are
defined in the Carlsbad SUSMP as an alternative to integrated LID design. The basins will
also be designed as infiltration basins that meet the treatment control best management
practice (TCBMP) requirements. The SUSMP requires that the extended detention basin
volume be based on the product of the County of San Diego’s 85th Percentile Isopluvial Map
(0.65 inches), the LID weighted runoff factor (0.10 for pervious surfaces), and the tributary
area. The minimum storage volume required for each of the three proposed basins was sized
using these criteria and the calculations and backup data are provided in this appendix. In
accordance with the SUSMP, additional design considerations and details were obtained
from Fact Sheet TC-22, Extended Detention Basins from the CASQA California Stormwater
Best Management Practice Handbooks.
Basin DMA, ac DMA, sf Runoff Factor 85th % Precip, in Storage Volume, cf
Northwest 7.14 311,018 0.1 0.65 1,685
Northeast 10.00 435,600 0.1 0.65 2,360
South 16.45 716,562 0.1 0.65 3,881
Table 1. Extended Detention Basin Sizing Table
Table 1 Notes:
The Drainage Management Areas (DMA) were delineated from the grading plans.
The graded surfaces will be pervious and landscaped. The associated runoff factor from SUSMP Table
4-2 is 0.1
The 85th percentile precipitation from the latest County of San Diego Map is 0.65 inches
The outlet risers will be sized for the 100-year flow rate (see Drainage Report)
The basins have designed based on the following criteria from TC-22:
- Minimum 3:1 side slopes
- Basin depth below riser set at approximately 4 feet
- Length to width ration of at least 1.5:1
- Use 10:1 side slope (10%) at basin entrance to minimize erosion and allow for access
The basins will also be used to provide infiltration to meet the TCBMP requirements. The
infiltration basins must drain in 72 hours and must be at least 10 feet above groundwater. The
project’s soils report indicates that groundwater is at elevations of 70 to 80 feet MSL, which
is 17 feet or more below the basins. The SUSMP indicates that the minimum surface area of
a basin is determined from the equation:
Minimum IMP Area = DMA Area × DMA Runoff Factor × IMP Sizing Factor
where,
IMP = integrated management practices, e.g., an infiltration basin.
IMP Area = surface area of the infiltration basin, sf
DMA Area = tributary drainage management area, sf
2
DMA Runoff Factor = 0.1 for natural areas
IMP Sizing Factor = 0.04 for treatment control
Table 2 summarizes the TCBMP sizing requirements for the infiltration basins. The basins
will store water to the elevation of the outlet riser (see paragraph below for the riser
analyses). The surface area provided in each basin below the top of riser exceeds the required
IMP infiltration area in Table 2, so the basins have sufficient area.
Basin DMA, ac DMA, sf
Runoff
Factor
Sizing
Factor
Min. IMP
Area, sf
Area
Provided, sf
Northwest 7.14 311,018 0.1 0.04 1,244 2,033
Northeast 10.00 435,600 0.1 0.04 1,742 2,807
South 16.45 716,562 0.1 0.04 2,866 3,870
Table 2. Infiltration Basin Sizing Table
The storage volume in Table 1 and infiltration area in Table 2 give an indication of the time
to drain from the basin. The volume divided by the area provided for any given basin yields
the maximum depth of water that must infiltrate into the ground within 72 hours. The
maximum volume over area provided is about 1 foot (3,881÷3,870). This equates to a
maximum infiltration rate of 0.17 inches per hour for 72 hours. The underlying soil layer will
be specified by the soils engineer during construction to provide this rate.
Each extended detention basin will contain a riser that will cause sediment to deposit in the
basin. The riser will also allow the 100-year flow to be conveyed out of the basin. The 100-
year flow rate is based on the proposed condition rational method results from the April 7,
2011, Drainage Report for South Coast Materials Quarry, by Chang Consultants. Each
outlet riser connects to a pipe that outflows into Buena Vista Creek. The flow rates at each
basin are summarized in Table 3.
Basin
100-Year Flow
Rate, cfs
Northwest 12
Northeast 33
South 87
Table 3. Summary of 100-Year Rational Method Results
for Desiltation Basin Riser Design
According to the Reclamation Plan drawing, the northwest and northeast basins will each
have a 42-inch high density polyethylene (HDPE) riser, while the south basin will have a 54-
inch HDPE riser. Orifice and weir calculations were performed for the risers and
corresponding 100-year flow rates using Bentley’s FlowMaster program. The results provide
the amount of head necessary to convey the 100-year flow through the risers and are included
in this appendix and summarized in Table 4. The more conservative of the weir and orifice
results for each riser governs. From Table 4, it is evident that weir flow governs in each case.
3
In order to ensure that the desiltation basins can handle runoff from the 100-year event, the
basins have been designed so the top of banks are higher than the top of risers plus the weir
headwater depth with a foot of freeboard.
Major Drainage
Basin
Weir Headwater
Depth, ft
Orifice Headwater
Depth, ft
Northwest 0.51 0.07
Northeast 1.00 0.51
South 1.61 1.29
Table 4. Summary of Weir and Orifice Analyses for Sedimentation Pond Risers
S E C T I O N 4 : L I D D E S I G N G U I D E
68 City of Carlsbad SUSMP— January 14, 2011
Underdrains shall be elevated to allow water to infiltrate the treatment volume.
Runoff from self-treating and self-retaining areas does not require any further treatment or
flow control.
TABLE 4-2. Runoff factors for surfaces draining to TCBMP/IMPs.
Surface Factor
Roofs 1.0
Concrete/Asphalt 1.0
Grouted Unit Pavers 1.0
Solid Unit Pavers on granular base, min. 3/16 inch joint
space 0.2
Pervious Concrete 0.1
Porous Asphalt 0.1
Crushed Aggregate 0.1
Turfblock 0.1
Amended, mulched soil 0.1
Landscape Areas 0.1
Areas draining to TCBMP/IMPs are multiplied by a sizing factor to calculate the required size of
the TCBMP/IMP. On most densely developed sites—such as commercial and mixed-use
developments and small-lot residential subdivisions—most DMAs will drain to TCBMP/IMPs.
More than one drainage area can drain to the same TCBMP/IMP. However, because the
minimum TCBMP/IMP sizes are determined by ratio to drainage area size, a drainage area may
not drain to more than one TCBMP/IMP. See Figures 4-4 and 4-5.
FIGURE 4-5. ONE DRAINAGE
Management Area cannot drain to more than one IMP.
Use a grade break to divide the DMA.
FIGURE 4-4. MORE THAN ONE
Drainage Management Area can drain to a single
IMP.
Project Description
Solve For Headwater Elevation
Input Data
Discharge 33.00 ft³/s
Crest Elevation 100.00 ft
Weir Coefficient 3.00 US
Crest Length 11.00 ft
Results
Headwater Elevation 101.00 ft
Headwater Height Above Crest 1.00 ft
Flow Area 11.00 ft²
Velocity 3.00 ft/s
Wetted Perimeter 13.00 ft
Top Width 11.00 ft
Worksheet for Basin 200 Riser - Weir
8/19/2010 1:47:06 PM
Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.11.00.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page
Project Description
Solve For Headwater Elevation
Input Data
Discharge 33.00 ft³/s
Centroid Elevation 100.00 ft
Tailwater Elevation 0.00 ft
Discharge Coefficient 0.60
Diameter 3.50 ft
Results
Headwater Elevation 100.51 ft
Headwater Height Above Centroid 0.51 ft
Tailwater Height Above Centroid -100.00 ft
Flow Area 9.62 ft²
Velocity 3.43 ft/s
Worksheet for Basin 200 Riser - Circular Orifice
8/19/2010 1:47:34 PM
Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.11.00.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page
Project Description
Solve For Headwater Elevation
Input Data
Discharge 12.00 ft³/s
Crest Elevation 100.00 ft
Weir Coefficient 3.00 US
Crest Length 11.00 ft
Results
Headwater Elevation 100.51 ft
Headwater Height Above Crest 0.51 ft
Flow Area 5.60 ft²
Velocity 2.14 ft/s
Wetted Perimeter 12.02 ft
Top Width 11.00 ft
Worksheet for Basin 300 Riser - Weir
8/19/2010 1:48:21 PM
Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.11.00.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page
Project Description
Solve For Headwater Elevation
Input Data
Discharge 12.00 ft³/s
Centroid Elevation 100.00 ft
Tailwater Elevation 0.00 ft
Discharge Coefficient 0.60
Diameter 3.50 ft
Results
Headwater Elevation 100.07 ft
Headwater Height Above Centroid 0.07 ft
Tailwater Height Above Centroid -100.00 ft
Flow Area 9.62 ft²
Velocity 1.25 ft/s
Worksheet for Basin 300 Riser - Circular Orifice
8/19/2010 1:48:56 PM
Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.11.00.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page
Project Description
Solve For Headwater Elevation
Input Data
Discharge 87.00 ft³/s
Crest Elevation 100.00 ft
Weir Coefficient 3.00 US
Crest Length 14.14 ft
Results
Headwater Elevation 101.61 ft
Headwater Height Above Crest 1.61 ft
Flow Area 22.83 ft²
Velocity 3.81 ft/s
Wetted Perimeter 17.37 ft
Top Width 14.14 ft
Worksheet for Basin 400 Riser - Weir
2/16/2011 10:33:13 PM
Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page
Project Description
Solve For Headwater Elevation
Input Data
Discharge 87.00 ft³/s
Centroid Elevation 100.00 ft
Tailwater Elevation 0.00 ft
Discharge Coefficient 0.60
Diameter 4.50 ft
Results
Headwater Elevation 101.29 ft
Headwater Height Above Centroid 1.29 ft
Tailwater Height Above Centroid -100.00 ft
Flow Area 15.90 ft²
Velocity 5.47 ft/s
Worksheet for Basin 400 Riser - Circular Orifice
2/16/2011 10:32:40 PM
Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03]
27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page