HomeMy WebLinkAbout; Municipal Golf Course Hydrology Rpt No Exhibits; Hydrology Report and Storm Water Mgmnt Plan Folg Course; 2004-07-01HYDROLOGY REPORT AND
STORM WATER MANAGEMENT PLAN
FOR CARLSBAD MUNICIPAL GOLF COURSE
July 2004
Revised November 2004
Prepared for:
CITY OF CARLSBAD
1200 Carlsbad Village Drive
Carlsbad, CA 92008
Prepared by:
P&D CONSULTANTS, INC.
8954 Rio San Diego Drive, Suite 610
SanDiego, CA92108
(619) 291-1475 Phone
(619) 291-1476 Fax
Job Number: 175766.0020
Prepared By: John Gerritsen
Reviewed By: Daniel A. Lee, P.E.
HYDROLOGY REPORT AND
STORM WATER MANAGEMENT PLAN
FOR CARLSBAD MUNICIPAL GOLF COURSE
TABLE OF CONTENTS
Section Page No.
INTRODUCTION AND APPLICABLE REGULATIONS in
1.0 DESCRIPTION OF PROPOSED PROJECT
1.1 Project Location 1
1.2 Project Description 1
1.3 Responsible Parties 1
1.4 Vicinity Map 2
1.5 Site Map 3.
2.0 WATER QUALITY ENVIRONMENT
2.1 Beneficial Uses 4
2.2 303(d) Status • 4
3.0 Characterization of Project Runoff
3.1 Existing Storm Water Quality 5
3.2 Identification of Future Pollutants 5
3.3 Site Hydrology 6
3.4 Water Quality Treatment Based on Quality Storm Systern Design 9
3.5 Adjacent Land Use 10
3.6 Soil Characteristics 10
4.0 Mitigation Measures To Protect Water Quality
4.1 Construction BMPs 11
4.2 Post Construction BMPs 11
5.0 Operation And Maintenance
5.1 Storm Water Management Program Maintenance Responsibility 13
6.0 Fiscal Resources and References 14
7.0 Summary / Conclusions 14
8.0 References 15
City of Carlsbad i Storm Water Management Plan
Revised November 2004
LIST OF MAPS Page
1 Vicinity Map 2
2 Site Map 3
3 Drainage Map, Proposed Conditions Appendix A
APPENDIX
A Charts and Tables
Figure
3-1 Intensity-Duration Chart
3-2 100-year 6-Hour Precipitation Chart
3-3 100-year 24-Hour Precipitation Chart
3-4 Runoff Coefficient Table
B Caltrans Notes and Details Page
Scheduling SS - 1
Silt Fence SC - 1
Fiber Rolls SC -5
Gravel Bag Berm SC -6
Street Sweeping and Vacuuming . SC -7
Storm Drain Inlet Protection sc-10
Stabilized Construction Entrance/ Exit TC -1
Water Conservation Practices NS - 1
Potable Water / Irrigation NS -7
Vehicle and Equipment Cleaning NS -8
Vehicle and Equipment Fueling NS -9
Vehicle and Equipment Maintenance NS -10
Concrete Curing NS -12
Material Delivery and Storage WM - 1
Material Use. WM -2
Stockpile Management WM -3
Spill Prevention and Control WM -4
Solid Waste Management WM -5
Hazardous Waste Management WM -6
Concrete Waste Management WM -8
Sanitary / Septic Waste Management WM -9
Liquid Waste Management WM-10
City of Carlsbad ii Storm Water Management Plan
Revised November 2004
INTRODUCTION AND APPLICABLE REGULATIONS
The Municipal Storm Water National Pollutant Discharge Elimination System (NPDES) Permit, Order
No. 2001-01 and NPDES No. CA0I08758, issued to San Diego County, San Diego Unified Port District
and 18 cities including the City of Carlsbad by the Califomia Regional Water Quality Control Board, San
Diego Region contains a requirement to develop and implement a jurisdictional Urban Runoff
Management Program.
The 1972 Clean Water Act established the National Pollutant Discharge Elimination System (NPDES)
permit program to regulate the discharge of pollutants from point sources to waters of the United States
(U.S.). Municipalities in San Diego County collect and discharge storm water to conveyance systems.
The San Diego Regional Water Quality Control Board (Regional Board) issued the required NPDES
permit (commonly referred to as the Municipal Storm Water Permit for San Diego Co-permittees) to local
jurisdictions including the City of Carlsbad, which requires the implementation of programs to reduce
pollutants in storm water and urban runoff. This permit, originally issued in 1990, was significantly
revised when it was renewed on February 21, 2001, as Order No. 2001-01, NPDES No. CA0108758.
"Waste Discharge Requirements for Discha:rges of Urban Runoff From the Municipal Separate Storm
Sewer Systems (MS4) Draining the Watersheds of the County of San Diego, the Incorporated Cities of
San Diego County, and the San Diego Unified Port District".
A Storm Water Management Plan (SWMP) is required under the City of Carlsbad Municipal Code,
Chapter 15.12. The purpose of this SWMP is to address the water quality impacts of the proposed
improvements of the site. Best Management Practices (BMPs) will be utilized to provide a long-term
solution to water quality. This SWMP is also intended to ensure the effectiveness of the BMPs through
proper maintenance that is based on long-term fiscal plarming. The SWMP is subject to revisions as
needed by the engineer.
This Storm Water Management Plan has been prepared under the direction of the following Registered
Civil Engineer. The Registered Civil Engineer attests to the technical information contained herein and
the engineering data upon which recommendations, conclusions, and decisions are based.
Daniel A. Lee
Registered Civil Engineer
City of Carlsbad iii Storm Water Management Plan
Revised November 2004
1.0 DESCRIPTION OF PROPOSED PROJECT
1.1 Project Location
The City of Carlsbad Municipal Golf Course project site encompasses approximately 400 acres
and is located southeast of Aqua Hedionda Creek in the City of Carlsbad. The site is bounded on
the south by Palomar Airport Road, on the west by Hidden Valley Road, and on the east by the
Palomar Airport and surrounding business parks. College Avenue bisects the property in a north
east/south west direction.
1.2 Project Description
1.2.1 Existing Condition
The proposed project is located in the northwestem quadrant of the City of Carlsbad. The
project site is composed of rolling hills, steep hillsides, and canyons. The northem portion of the
site is currently utilized for agricultural production. A variety of vegetation exists on the project
site and includes areas of coastal sage scmb and riparian habitat. Elevations of the project site
range from approximately 320 feet above mean sea level (AMSL) at the highest knoll in the
eastem portion of the site, to 20 feet AMSL in the northwestem portion of the site. The project
site consists of approximately 397 acres of land and is primarily vacant, with the exception of
several SDG&E transmission lines and a 20-inch gas line that traverses the site, and a shooting
range.
1.2.2 Developed Condition
The primary component of the proposed project is the development of an 18-hole championship
golf course which will cover xxx acres. The project will also include the development of a 1.7-
acre club house, 3.75-acre parking lot, 2.0-acre conference center, 1.6-acre maintenance facility,
and a 9.2-acre driving range. The proposed project will also include the development of two
industrial sites and the relocation of an existing shooting range.
1.3 Responsible Parties
The City of Carlsbad will initially be responsible for implementation and maintenance of all
storm water management devices and practices. With the coinpletion of the golf course, this
responsibility will be conveyed to a legally created maintenance entity. Proper proof of
maintenance will be reported to the appropriate agency.
City of Carlsbad 1 Storm Water Management Plan
Revised November 2004
Figure 1. Vicinity Map
City of Carlsbad 2 Storm Water Management Plan
Revised November 2004
Figure 2 - Site Map
City of Carlsbad Storm Water Management Plan
Revised November 2004
2.0 WATER QUALITY ENVIRONMENT
2.1 Beneficial Uses
Under the Clean Water Act, "the beneficial use designation of surface waters of the state must
take into consideration, the use and value of water for public water supplies. Protection and
propagation of fish, shellfish and wildlife, recreation in and on the water, agricultural, industrial
and other purposes including navigation. There are significant offsite flows which traverse this
site. Runoff from the entire site will flow (after groimdcover and landscaping cleansing and
depoUuting) into the Agua Hedionda watershed north of the Ridge Line and into the Encinas
Creek watershed to the south.
2.1.1 Surface Waters
The existing_beneficial uses for inland surface waters include warm freshwater habitat (WARM).
The existing_beneficial uses for Agua Hedionda and Encinas Creek watersheds, which the site
mnoff contacts includes; navigation (NAV); contact water recreation (REC-1); noncontact water
recreation (RBC-2); commercial and sport fishing (COMM), preservation of biological habitats
of special significance (BIOL); wildlife habitat (WILD); rare, threatened, or endangered species
(RARE); marine habitat (MAR); aquaculture (AQUA); spawning reproduction, and/or early
development (SPWN); migration of aquatic organisms (MIGR)j and shellfish harvesting
(SHELL). There are no additional potential beneficial uses listed. Treatment of runoff from the
subject site is for the purpose of reducing pollution impacts to these beneficial water uses, more
specifically the downstream watersheds described above.
2.1.2 Groundwater
There are no existing or proposed uses for groundwater. The site's water supply will be obtained
from the City of Carlsbad municipality, not from onsite wells.
2.2 303(D) Status
According to the 2002 Califomia 303(d) list published by the San Diego Regional Water Quality
Control Board, the Agua Hedionda Creek is listed as an impaired waterbody. The Agua
Hedionda and Encinas Creek watersheds are the eventual receiving bodies of water of the
drainage from this project and are on the 303(d) listing.
City of Carlsbad 4 Storm Water Management Plan
Revised November 2004
3.0 CHARACTERIZATION OF PROJECT RUNOFF
3.1 Existing Storm Water Quality
The existing topography is characterized by rolling hills and grassland, and native vegetation.
Farming activity currently takes place in the extreme northem part of the site, north of Macario
Canyon in the area of the planned extension of Faraday Drive. A ridge mnning east and west
through the middle of the project site divides the area into two distinct drainage basins. The
northerly basin surface drains into Macario Canyon. On the eastem boundary at Macario
Canyon, a fairly large flow from the Carlsbad Research Center enters the project site. This flow
is attenuated by a detention basin that has been installed adjacent to existing Faraday Drive at the
eastem project site boundary.
Until recently, the southerly basin surface drained to existing culverts along Palomar Airport
Road. However, the recent constmction of Hidden Valley Road on the westem boundary has cut
off the dual 48" culverts under Palomar Airport Road in the southwestem comer of the site.
These culverts previously carried a large amount of flow from the southwestem subarea of the
project site. The existing 18" culvert remaining on the east side of Hidden Valley Road is
currently the only outlet for this subarea and by undersized to carry the higher mnoff storms
without backing up mnoff, or even overtopping of Palomar Airport Road. This existing 18"
culvert just east of Hidden Valley Road was not intended to carry the full amount of mnoff from
the upstream subarea as mentioned above, and represents an existing condition that may need to
be corrected.
3.2 IdentiHcation Of Future Pollutants
The proposed golf course occupies approximately 203 acres of the 400-acre site. Proposed golf
course stmctures consist of the clubhouse, pumphouse and two restrooms out on the golf course.
There are two proposed industrial pads that are part of the overall development program. They
are located on both sides of College Boulevard, at the northeasterly boundary. Over 90% of the
site will be golf course, re-vegetated, or will remain undisturbed natural terrain. The golf course
and related landscaping will be maintained with enviro-fiiendly fertilizers and pesticides to
minimize "chemical" nmoff. Runoff from roofs, hardscape, and parking may contain
contaminants of gasoline, oil, coolants, transmission and brake fluids, road tars, mbber,
detergent, and relatively small quantities of sediment from the natural areas.
City of Carlsbad 5 Storm Water Management Plan
Revised November 2004
3.3 Site Hydrology
The general requirement to maintain predevelopment discharge rates is addressed for the site by
incorporating retention basins into the storm drain system design where needed. In general
mnoff flow quantities will be nearly the same as the natural hillsides because of the absorption
rates for golf course turf surfaces.
3.3.1 Hydrology Calculations
Method
This report analyzed the existing and proposed project conditions for an approximately 400 acre
project in the City of Carlsbad. Hydrology calculations for the 100 year storm follow the design
standards issued in the June 2003 San Diego County Hydrology Manual. As the project consists
of less than one square mile (640 Acres) the Rational Method (Q=CIA) is used to determine peak
flows and discharge from the project site.
A soil type "D" was selected from the Soil Hydrologic Groups Chart included in the Appendix.
Type "D" is defined as having the highest mnoff potential and was chosen as a conservative
average of the entire project site. The mnoff coefficient C was chosen using this soil type and
the lookup table included in the Appendix. Although the table lists a C value .35 for natural
terrain with "D" type soil, fiirther research based on the grading and landscaping of turf slopes
typical to most golf courses results in a more accurate C value of 45 percent (.45). Other largely
developed areas of the golf course including the club house and maintenance area will use a .95
C value.
A 6 hour point rainfall of 2.75 for the 100 year storm has been pulled from the corresponding
Isopluvial. This is in the 45-65 percent range of the 24 hour point rainfall value of 5, and
therefore does not need to be adjusted. All rainfall intensities will be calculated based on this
2.75 point rainfall and a time to concenfration (Tc) from the Kirpich formula. A minimum Tc of
5 minutes will be used for all basins.
Basin subareas (A) are determined based on the path the rainfall will take when mnning
downhill. The boimdaries are defined by ridges on the topography, swales, brow ditches and
inlets in to the storm drain system. All the rain falling within a basin will flow to the lowest
point in the basin, defined as a concentration point. The Rational method Q=CIA determines the
peak flow in cubic feet per second at this point of concentration.
City of Carlsbad 6 Storm Water Management Plan
Revised November 2004
The hydrologic study of this report was done using iStormCAD 5.5 from Haestad Methods. All
pipes are circular, the private system being a PCV pipe having diameters equal to 12 inches and
less and the public system being a concrete pipe with diameters larger than 12 inches.
StormCAD 5.5 uses Manning's equation to calculate sizes of the pipes and gives a Manning n of
.01 to the PVC and .13 to the concrete pipes.
Existing Hydrology
Exhibit "A" shows the drainage basins used in the existing hydrology analysis of the project.
The existing topography is characterized by rolling hills with grassland vegetation covering most
of the site. Farming activity currently takes place in the exfreme northem part of the site north of
Macario Canyon in the area of fiature Faraday Drive. A ridge mnning east and west through the
middle of the site divides the area into two distinct drainage basins.
The northerly basin surface drains into Macario Canyon. On the eastem boundary at Macario
Canyon, a fairly large flow from the Carlsbad Research Center enters the project. This flow has
been attenuated by the installation of a detention basin adjacent to existing Faraday Drive at the
eastem boundary.
The southerly basin surface drains to existing culverts along Palomar Airport Road. These
culverts are indicated on the exhibit. Recent constmction of Hidden Valley Road on the westem
boundary has cut off the dual 48" culverts under Palomar Airport Road in the southwestem
comer of the site which carried a large amount of flow from the Golf Course area. The existing
18" culvert remaining on the east side of Hidden Valley Road will be the only outlet for this
area. This pipe may be undersized to carry the higher mnoff storms without backing up mnoff,
or even overtopping of Palomar Airport Road.
Analysis
The drainage map smnmarizes the analysis of the existing hydrology for each drainage basin.
The 100 year retum period flows were calculated to assess the existing improvements and to
establish a baseline for comparison to the post-project or proposed hydrology.
Offsite flows from the Carlsbad Research Center and associated detention basins has been
obtained from the stonn drain reports prepared in conjimction with that development and
provided by the City of Carlsbad.
City of Carlsbad 7 Storm Water Management Plan
Revised November 2004
The existing culverts under Palomar Airport Road and in College Boulevard accepting drainage
from the site were evaluated for adequacy for the existing 100-year flow. The results of this
analysis are shown in Table 1. This analysis confirms that the existing culverts have been sized
to accept the existing 100 year mnoff, except the existing 18" culvert just east of Hidden Valley
Road. This pipe was not intended to carry the frill amount of nmoff from the upstream basin as
mentioned above, and represents an existing condition that will need to be corrected.
The hydrology report for the existing College Boulevard storm drain was not available at the
City at the time of preparation of this report. Runoff estimates and approximate capacity
calculations were done for these existing pipes to determine if they are adequate to accommodate
the existing and proposed project. Table 1 summarized the flows for these existing pipes. It
should be noted that the flows analyzed in this report are for the 100 year storm and these
culverts may, have been sized to carry the 10 year storm. It that event, flow-by or overtopping
may occur for stonn events greater than the 10 year storm.
Proposed Hydrology
The proposed golf course grading and improvements were analyzed to determine additional
impacts, if any, on the existing drainage improvements within the project site. For this analysis,
a "C" value of 0.55 was used for proposed sodded and otherwise vegetated areas in determining
the 100-year mnoff. Since the existing analysis also used this same "C" value, the only increase
in mnoff is expected from the clubhouse and fiiture golf-related commercial sites.
Brow ditches and storm drain pipes proposed with the golf course project are shown
schematically with preliminary sizes. Final sizing of these pipes and appurtenant improvements
shall be done with the final engineering design. The proposed bridges across the Mecario
Canyon will also be designed in the final engineering. The preliminary indication is that they
will span a portion of the riparian area and low flow channel, but some fill for the abutments is
expected into the floodplain.
Analysis
The proposed hydrology analysis is summarized in the exhibit. For Palomar Airport Road and
College Boulevard, the existing culverts were checked for adequacy and the results are shown in
Table 2. As noted above, the culverts in College Boulevard may have been sized to carry the 10
year storm. For storm events greater than this retum period, flow-by or overtopping may occur.
City of Carlsbad 8 Storm Water Management Plan
Revised November 2004
3.4 Water Quality Treatment Based On Water Quality Storm System Design
The majority of the storm drain lines will collect surface drainage from golf course surfaces
containing minimal amounts of contaminants. Approximately 75% of the golf coiurse drainage
will outlet onto natural terrain and natural drainage courses, not directly into Macario Creek and
will be filtered as it flows downstream towards Macario Creek to the North or Palomar Airport
Road to the south. Retention-filtration basins are part of the design at outfall locations where
needed. Sheetflow filtration is built into holes 12, 13, 14, 15, and 16 by way of crossflow
drainage across the fairways into a "golf-rough" with unfertilized vegetation and then through a
"native-rough" to be filtered before entering into Macario Creek. This combination rough mns
continuously on the downhill edge of the fairways with an average width of 40 ft which varies
depending on area of mnoff being collected. The average cross slope for this area is less than a
4:1 slope. No un-filtered concentrated drainage will outlet into Macario Creek. This method of
water quality treatment has a direct conelation with Califomia Stormwater Quality Association
BMPs as follows:
Treatment Control BMPs
TC-30 Vegetated Swale
TC-31 Vegetation Buffer Strip
Source Control BMPs
SD-10 Site design & landscape planning
SD-12 Efficient Irrigation
There will also be inlet filtration inserts incorporated into the system as needed. Runoff from the
two industrial lots will be treated by way of filtration devices built into the inlets and/or as a
result of outletting onto natural ground and filtered as it flows downstream. In summary,
because of the nature of golf course land use, high water quality mnoff is accomplished as a
result of this land use.
Volume-based BMP design standards apply to BMPs whose primary mode of pollutant removal
depends on the volumetric capacity of the BMP. Examples of BMPs in this category includes
detention basins, retention basins, and infiltration. Typically, a volume-based BMP design
criteria calls for the capture and infilfration or freatment of a certain percentage of the mnoff
from the project site, usually in the range of the 75* to 85* percentile average annual mnoff
volume. Because of the nature of a golf course , the percent of infiltration/filtration exceeds the
85* percentile in terms of average daily mnoff associated with irrigation and typical average
annual storm flows.
City of Carlsbad 9 Storm Water Management Plan
Revised November 2004
3.5 Adjacent Land Use
Much of the adjacent land is natural hillsides with industrial use to the northeast and east.
Legoland is adjacent to the west with one developed industrial site across Palomar Airport Road
at the southwest comer.
3.6 Soil Characteristics
The soil quality in this area tends to be sandy to fine, type "D". No additional adverse impact
due to soil quality is anticipated because of the proposed development.
4.0 MITIGATION MEASURES TO PROTECT WATER QUALITY
During the constmction phase, the project is subject to the requirements of the "Waste Discharge
Requirements for Discharges of Storm Water Runoff Associated with Constmction Activity" as
indicated by the State Water Resources Control Board (SWRCB) Order No. 99-08-DWQ
National Pollutant Discharge Elimination System (NPDES) General Permit No. CAS000002
(General Constmction Permit). The State Water Resources Control Board adopted the General
Constmction Permit on August 19, 1999. For coverage by the General Constmction Permit, the
project owner is required to submit to the SWRCB a Notice of Intent (NOl) to comply with the
General Constmction Permit, and develop a Stomi Water PoUutioti Prevention Plan (SWPPP)
describing best management practices (BMPs) to be used during and after constmction to
prevent the discharge of sediment and other pollutants in storm water mnoff from the project. In
order to terminate coverage under the General Constmction Permit, the developer must submit a
Notice of Termination (NOT) and a Post-Construction Storm Water Operation and Management
Plan (PCSWOMP), according to Section A. 10 of the General Constmction Permit, to the
Regional Water Quality Control Board (RWQCB).
In the site's present natural state the pollutant of concem with the site is primarily sediment.
During constmction the pollutants of concem on the site are sediment and non-visible pollutants.
The site owner is responsible to prevent these pollutants from leaving the site by implementing
temporary BMPs. Typical temporary BMPs that may be used during constmction include good
housekeeping practices and erosion and sediment control measures. Good housekeeping
practices include practices such as street sweeping, waste disposal, vehicle and equipment
maintenance, materials storage, minimization of hazardous materials and proper handling and
storage of hazardous materials. Typical erosion and sediment control measures include silt
fence, fiber rolls, gravel bags, temporary desilting basins, velocity check dams, temporary
ditches or swales, storm water inlet protection, soil stabilization measures such as erosion control
mats, tackifier, or hydroseed, and other measures.
City of Carlsbad 10 Storm Water Management Plan
Revised November 2004
4.1 Construction BMPs
Available constmction BMPs are as follows:
Scheduling
Soil Binders
Silt Fence
Fiber Rolls
Gravel Bag Berm
Sfreet Sweeping and Vacuuming
Storm Drain Inlet Protection
Stabilized Constmction Entrance/ Exit
Water Conservation Practices
Potable Water / Irrigation
Vehicle and Equipment Cleaning
Vehicle and Equipment Fueling
Vehicle and Equipment Maintenance
Concrete Curing
Material Delivery and Storage
Material Use
Stockpile Management
Spill Prevention and Control
Solid Waste Management
Hazardous Waste Management
Concrete Waste Management
Sanitary / Septic Waste Management
Liquid Waste Management
Constmction BMPs for this project are selected, and will be constmcted and maintained, so as to
comply with all applicable ordinances and guidance documents.
4.2 Post-Construction BMPs
Pollutants of concem as noted in Section 3.2 will be addressed through, two types of BMPs.
These types of BMPs are site design and source and/or treatment control.
Site design BMPs reduce the need for source and/or treatment control BMPs, and source control
BMPs may reduce the amount of freatment control BMPs needed. Commercial and industrial
facilities are required to have on-site Treatment Control BMPs appropriate for the potential
City of Carlsbad 11 Storm Water Management Plan
Revised November 2004
pollutants generated at the site. As described below, all priority projects shall consider,'
incorporate, and implement where detemiined applicable and feasible by the City of Carlsbad,
storm water BMPs into the project design, in the following progression: (1) Site Design BMPs,
(2) Source Control BMPs, and (3) Treatment Control BMPs.
The project will provide permanent stomi water BMPs to ensure that water quality treatment is
provided prior to storm water mnoff discharging from the project site. The specifics regarding
design of the section structural treatment control BMPs (as applicable) will be discussed in
Section 5.0 of this WQTR. Underlined text and italicized text in the following discussion
represents headings and line items from Section V.2 of the Storm Water Standards Manual.
Portions of the italicized text are condensed from the Storm Water Standards Manual.
4.2.1 Site Design BMPs
"Site design BMP" means any project design feature that reduced the creation or severity of
potential pollutant sources, reduces the alteration of the project site's natural flow regime, or
maintains or reduces pre-development downstream erosion and protects strealm habitat. All storm
drain inlets shall be equipped with trash racks, and stenciled with water quality waming signs.
4.2.2 Source Control BMPs
Source control BMPs will consist of measures to prevent polluted mnoff. This will include an
educational information component to be passed on to all new owners. It will include the
following:
Storm Water Runoff Pollution Fact Sheet
Storm Water Rimoff Pollution Prevention Tips for Users
Storm Water Pollution Prevention Yard Work (Landscaping, Gardening, Pest Control);
Storm Water Pollution Prevention Site Waste
Storm Water BMP Water Feature Maintenance
The functional aspect of day to day operation will include the following as BMPs and will be
incorporated into the private infrastmcture to meet stormwater management objectives.
• Landscape filfration areas around the proposed stmctures for landscape mnoff
• Grease traps for the food preparation areas
• Local building related drainage systems within landscaped planters
• Catch basin & inlet bio-filters as may be needed in parking & cart staging areas
City of Carlsbad 12 Storm Water Management Plan
Revised November 2004
5.0 OPERATION AND MAINTENANCE
5.1 Stormwater Management Program Maintenance Responsibility
The project's owners and their Successors indefinitely, shall be responsible for maintenance and
repair of all storm water pollution prevention measures.
Monitoring Program
A monitoring program shall be implemented as part of the golf course operation and will include
the following:
• Weekly irrigation inspection program for the 1^' year of operation to evaluate and document
efforts to minimize or eliminate dry weather nuisance flows to natural drainage courses.
• Fail safe shut off equipment for malfimctioning automatic irrigation systems.
• Water usage/leakage detection equipment.
• Monitoring report based on the City of Carlsbad Municipal Golf Course Water Quality
monitoring Plan to evaluate:
o 3 storms/year (ongoing evaluation)
o 1 dry weather water quality samples/year (shortly after an irrigation cycle)
Charter
The project's owners, being duly responsible for upholding their maintenance responsibilities in
accordance with the Clean Water Act and Califomia Water Code, shall be responsible for
maintenance and repair of all storm water pollution prevention measures. Such responsibility
shall mn fully with the use of such land, and all successors or assigns to such land shall be made
aware of their responsibilities with regard to storm water pollution prevention.
Maintenance Activities per BMPs
The maintenance activities as specifically identified herein, shall include but not necessarily be
limited to maintenance of groundcover and replacement of dead or otherwise ineffectual
groundcover, maintenance of irrigation systems for such cover, regular inspections and cleaning
the site of debris, and cleaning of the vehicle areas and proper disposal of waste materials.
Additionally, the parking lot will be swept with a regenerative sweeper on a regular basis.
City of Carlsbad 13 Storm Water Management Plan
Revised November 2004
6.0 FISCAL RESOURCES AND REFERENCES
6.1 Agreements
The monetary responsibilities to maintain such a system may be enforced upon the present
owners of the property (and successors by agreement), by the City of Carlsbad, in accordance
with the regulations set forth in the Clean Water Act and the Califomia Water Code. This
written agreement may be required by the City of Carlsbad prior to approval of building permits
or building occupancy.
7.0 SUMMARY/CONCLUSIONS
This SWMP has been prepared in accordance with the Watershed Protection, Storm Water
Management, and Discharge Control Ordinance and the Storm Water Standards Manual. This
SWMP has evaluated and addressed the potential pollutants associated with this project and their
effects on water quality. A summary of the facts and findings associated with this project and
the measures addressed by this SWMP is 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 constmction and operation of this project.
The proposed development and postdevelopment BMPs address mitigation measures to protect
water quality, and protect water quality objectives and beneficial uses to the maximum extent
practicable.
The development of the site as proposed will be an improvement in terms of storm water
conveyance and pollution prevention compared to the existing condition.
City of Carlsbad 14 Storm Water Management Plan
Revised November 2004
8.0 REFERENCES
Clean Water Act, United States Government, as prepared in 1972 and amended in 1977.
Califomia Water Code - Porter Cologne Water Quality Control Act of 1969, State of
Califomia, U.S.
Water Quality Control Plan for the San Diego Basin (9), Califomia Regional Water Quality
Control Board - San Diego Region, May 5,1998.
Califomia State Water Resources Control Board '303d' List of Impaired Water Bodies,
2002.
Caltrans Constmction Site Best Management Practices (BMPs) Manual, Califomia Department
of Transportation March 2003.
San Diego Bay Watershed Urban Runoff Management Program, San Diego Port District,
January 2003
City of Carlsbad 15 Storm Water Management Plan
Revised November 2004
APPENDIX A
CHARTS AND TABLES
Figures
3-1 Intensity-Duration Chart
3-2 100- Y ear, 6-Hour Precipitation Chart
3 -3 100- Year, 24-Hour Precipitation Chart
3-4 Runoff Coefficient Table
CALCULATIONS AND MAP
Hydrology Calculations
Drainage Map, Proposed Conditions
City of Carlsbad A Storm Water Management Plan
Revised November 2004
APPENDIX B
CALTRANS NOTES AND DETAILS
FOR BMPs
Scheduling SS -1
Soil Binders SS - 5
Silt Fence SC-1
Fiber Rolls SC-5
Gravel Bag Bemi SC - 6
Street Sweeping and Vacuuming SC - 7
Storm Drain Inlet Protection SC - 10
Stabilized Constmction Entrance/ Exit TC - 1
Water Conservation Practices NS - 1
Potable Water / Inigation NS - 7
Vehicle and Equipment Cleaning NS - 8
Vehicle and Equipment Fueling NS - 9
Vehicle and Equipment Maintenance NS - 10
Concrete Curing NS - 12
Material Delivery and Storage WM -1
Material Use WM - 2
Stockpile Management WM - 3
Spill Prevention and Control WM - 4
Solid Waste Management WM - 5
Hazardous Waste Management WM - 6
Concrete Waste Management WM - 8
Sanitary / Septic Waste Management WM - 9
Liquid Waste Management WM - 10
City of Carlsbad B Storm Water Management Plan
Revised November 2004