HomeMy WebLinkAboutParcel Map 38166 WQMPCity of Temecula
WATER QUALITY MANAGEMENT PLAN (WQMP)
LANTERN CREST TEMECULA
PA19-1452, LD21-3700
SOUTHEAST CORNER OF DATE STREET & YNEZ ROAD
APN’s: 916-400-043, 044, 062, 064 & 065
PREPARED BY:
Name Polaris Development Consultants, Inc.
Address 2514 Jamacha Road, Suite 502-31
El Cajon, CA 92019
Phone (619) 248-2932
Email joel@polarisdc.com
PREPARED FOR:
Name Lantern Crest at Temecula, LLC.
Address 800 Lantern Crest Way
Santee, CA 92071
Phone (619) 449-0249
Email mgrant@mgrantcompanies.com
OCTOBER 7, 2024
APPROVED BY: _______________________
APPROVAL DATE: _____________________
PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 9
Template Date: September 26, 2019 Preparation Date: November 3, 2022
Provide details regarding the proposed project site drainage conveyance network, including
storm drains, concrete channels, swales, detention facilities, stormwater treatment facilities,
natural or constructed channels, and the method for conveying offsite flows through or around
the proposed project site. Identify all discharge locations from the proposed project site along
with a summary of the conveyance system size and capacity for each of the discharge
locations. Provide a summary of pre- and post-project drainage areas and design flows to each
of the runoff discharge locations. Reference the drainage study for detailed calculations.
Describe proposed site drainage patterns:
The proposed project will collect runoff in grated inlets within the drive aisles and convey the
runoff in underground pipes to the biofiltration basin in the southwest corner of the site. Runoff
will percolate through the basin soil matrix and into the native soil. Large storm flows that cannot
be infiltrated into the native soil will be captured in an underdrain and/or an overflow inlet, which
will convey the runoff to the west into the existing storm drain in Date Street. A small amount of
runoff at the easterly entry will be captured and treated with pervious pavers. The runoff on
Equity Drive on the south side of the project cannot be treated in the biofiltration area due to its
lower elevation, so it will be treated with an inlet filter. To offset this uncaptured area, a portion
of the runoff from the existing pavement on the south side of Ynez Road and the east side of
Date Street will be captured and directed into the biofiltration area. This off-site area of Ynez
Road and Date Street will be equal to or greater than the area of DMA #4.
Step 1.3: Other Site Requirements and Constraints
When applicable, list other site requirements or constraints that will influence stormwater
management design, such as zoning requirements including setbacks and open space, or local
codes governing minimum street width, sidewalk construction, allowable pavement types, and
drainage requirements.
No constraints.
PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 11
Template Date: September 26, 2019 Preparation Date: November 3, 2022
Step 2: Strategy for Meeting PDP Performance Requirements
PDPs must implement BMPs to control pollutants in stormwater that may be discharged from a
project (see Chapter 5). PDPs subject to hydromodification management requirements must
implement flow control BMPs to manage hydromodification (see Chapter 6). Both stormwater
pollutant control and flow control can be achieved within the same BMP(s). Projects triggering
the 50% rule must address stormwater requirements for the entire site.
Structural BMPs must be verified by the City at the completion of construction. This may include
requiring the project owner or project owner's representative and engineer of record to certify
construction of the structural BMPs (see Chapter 1.12). Structural BMPs must be maintained
into perpetuity, and the City must confirm the maintenance (see Chapter 7).
Provide a narrative description of the general strategy for pollutant control and flow control at
the project site in the box below. This information must describe how the steps for selecting and
designing stormwater pollutant control BMPs presented in Chapter 5.1 of the BMP Design
Manual were followed, and the results (type of BMPs selected). For projects requiring flow
control BMPs, indicate whether pollutant control and flow control BMPs are integrated or
separate. At the end of this discussion, provide a summary of all the BMPs within the project
including the type and number.
Describe the general strategy for BMP implementation at the site.
The project site is exempt from hydromodification, so only pollutant control BMP's will be
provided. The site is currently graded so that most of the site drains to the southwest corner and
the runoff is collected and conveyed into the public storm drain system in Date Street. The
proposed BMP design consists of a biofiltration basin in the southwest corner of the site that will
provide the required pollutant control for DMA’s 1 and 5, and pervious pavers that will provide
pollutant control for DMA 2. DMA 3 is a self-mitigating area. The runoff on Equity Drive on the
south side of the project cannot be treated in the biofiltration area due to its lower elevation, so it
will be treated with an inlet filter. To offset this uncaptured area, a portion of the runoff from the
existing pavement on the south side of Ynez Road and the east side of Date Street (DMA #5)
will be captured and directed into the biofiltration area. This off-site area of Ynez Road and Date
Street will be equal to or greater than the area of DMA #4.
(Continue on following page as necessary.)
BF-2 Nutrient Sensitive Media Design
E-134 July 2018
E.19 BF-2 Nutrient Sensitive Media Design
Some studies of biofiltration with underdrains have observed export of nutrients, particularly
inorganic nitrogen (nitrate and nitrite) and dissolved phosphorus. This has been observed to be a
short-lived phenomenon in some studies or a long term issue in some studies. The composition of
the soil media, including the chemistry of individual elements is believed to be an important factor in
the potential for nutrient export. Organic amendments, often compost, have been identified as the
most likely source of nutrient export. The quality and stability of organic amendments can vary
widely.
The biofiltration media specifications contained in the County of San Diego Low Impact
Development Handbook: Appendix G - Biofiltration Soil Specification (June 2014, unless
superseded by more recent edition) and the City of San Diego Low Impact Development Design
Manual (page B-18) (July 2011, unless superseded by more recent edition) were developed with
consideration of the potential for nutrient export. These specifications include criteria for individual
component characteristics and quality in order to control the overall quality of the blended mixes.
As of the publication of this manual, the June 2014 County of San Diego specifications provide
more detail regarding mix design and quality control.
The City and County specifications noted above were developed for general purposes to meet
permeability and treatment goals. In cases where the BMP discharges to receiving waters with
nutrient impairments or nutrient TMDLs, the biofiltration media should be designed with the
specific goal of minimizing the potential for export of nutrients from the media. Therefore, in
addition to adhering to the City or County media specifications, the following guidelines should be
followed:
1. Select plant palette to minimize plant nutrient needs
A landscape architect or agronomist should be consulted to select a plant palette that minimizes
nutrient needs. Utilizing plants with low nutrient needs results in less need to enrich the biofiltration
soil mix. If nutrient quantity is then tailored to plants with lower nutrient needs, these plants will
generally have less competition from weeds, which typically need higher nutrient content. The
following practices are recommended to minimize nutrient needs of the plant palette:
Utilize native, drought-tolerant plants and grasses where possible. Native plants
generally have a broader tolerance for nutrient content, and can be longer lived in
leaner/lower nutrient soils.
Start plants from smaller starts or seed. Younger plants are generally more tolerant of
lower nutrient levels and tend to help develop soil structure as they grow. Given the lower
cost of smaller plants, the project should be able to accept a plant mortality rate that is
somewhat higher than starting from larger plants and providing high organic content.
2. Minimize excess nutrients in media mix
BF-2 Nutrient Sensitive Media Design
E-135 July 2018
Once the low-nutrient plant palette is established (item 1), the landscape architect and/or
agronomist should be consulted to assist in the design of a biofiltration media to balance the
interests of plant establishment, water retention capacity (irrigation demand), and the potential for
nutrient export. The following guidelines should be followed:
The mix should not exceed the nutrient needs of plants. In conventional landscape
design, the nutrient needs of plants are often exceeded intentionally in order to provide a
factor of safety for plant survival. This practice must be avoided in biofiltration media as
excess nutrients will increase the chance of export. The mix designer should keep in mind
that nutrients can be added later (through mulching, tilling of amendments into the surface),
but it is not possible to remove nutrients, once added.
The actual nutrient content and organic content of the selected organic amendment
source should be determined when specifying mix proportions. Nutrient content (i.e.,
C:N ratio; plant extractable nutrients) and organic content (i.e, % organic material) are
relatively inexpensive to measure via standard agronomic methods and can provide
important information about mix design. If mix design relies on approximate assumption
about nutrient/organic content and this is not confirmed with testing (or the results of prior
representative testing), it is possible that the mix could contain much more nutrient than
intended.
Nutrients are better retained in soils with higher cation exchange capacity. Cation
exchange capacity can be increased through selection of organic material with naturally high
cation exchange capacity, such as peat or coconut coir pith, and/or selection of inorganic
material with high cation exchange capacity such as some sands or engineer ed minerals (e.g.,
low P-index sands, zeolites, rhyolites, etc). Including higher cation exchange capacity
materials would tend to reduce the net export of nutrients. Natural silty materials also
provide cation exchange capacity; however potential impacts to permeability need to be
considered.
Focus on soil structure as well as nutrient content. Soil structure is loosely defined as the
ability of the soil to conduct and store water and nutrients as well as the degree of aeration
of the soil. Soil structure can be more important than nutrient content in plant survival and
biologic health of the system. If a good soil structure can be created with very low amounts
of organic amendment, plants survivability should still be provided. While soil structure
generally develops with time, biofiltration media can be designed to promote earlier
development of soil structure. Soil structure is enhanced by the use of amendments with
high humus content (as found in well-aged organic material). In addition, soil structure can
be enhanced through the use of organic material with a distribution of particle sizes (i.e., a
more heterogeneous mix).
Consider alternatives to compost. Compost, by nature, is a material that is continually
evolving and decaying. It can be challenging to determine whether tests previously done on a
given compost stock are still representative. It can also be challenging to determine how the
properties of the compost will change once placed in the media bed. More stable materials
BF-2 Nutrient Sensitive Media Design
E-136 July 2018
such as aged coco coir pith, peat, biochar, shredded bark, and/or other amendments should
be considered.
With these considerations, it is anticipated that less than 10 percent organic amendment by volume
could be used, while still balancing plant survivability and water retention. If compost is used,
designers should strongly consider utilizing less than 10 percent by volume.
3. Design with partial retention and/or internal water storage
An internal water storage zone, as described in Fact Sheet PR-1 is believed to improve retention of
nutrients. For lined systems, an internal water storage zone worked by providing a zone that
fluctuates between aerobic and anaerobic conditions, resulting in nitrification/denitrification. In
soils that will allow infiltration, a partial retention design (PR-1) allows significant volume reduction
and can also promote nitrification/denitrification.
Acknowledgment: This fact sheet has been adapted from the Orange County Technical Guidance
Document (May 2011). It was originally developed based on input from: Deborah Deets, City of
Los Angeles Bureau of Sanitation, Drew Ready, Center for Watershed Health, Rick Fisher, ASLA,
City of Los Angeles Bureau of Engineering, Dr. Garn Wallace, Wallace Laboratories, Glen Dake,
GDML, and Jason Schmidt, Tree People. The guidance provided herein does not reflect the
individual opinions of any individual listed above and should not be cited or otherwise attributed to
those listed.
Refer to maintenance information provided in the Biofiltration (BF-1) Fact Sheet. Adjust
maintenance actions and reporting if required based on the specific media design.
Maintenance Overview
City of Temecula
STRUCTURAL BMP VERIFICATION PACKAGE
Project Information
Project Name Lantern Crest at Temecula
Record ID (e.g., grading/improvement plan
number)
LD21-3700
Project Address
East side of Date Street, south of Ynez Road
Assessor's Parcel Number(s) (APN(s)) 916-400-43, 44, 62, 64 & 65
Project Watershed
(Complete Hydrologic Unit, Area, and
Subarea Name with Numeric Identifier)
Santa Margarita
902.3 Murrieta
Responsible Party for Construction Phase
Developer's Name Lantern Crest at Temecula, LLC
Address
800 Lantern Crest Way
Santee, CA 92071
Email Address Mgrant@mgrantcompanies.com
Phone Number 619-449-0249
Engineer of Work Polaris Development Consultants, Inc.
Engineer's Phone Number 619-248-2932
Responsible Party for Ongoing Maintenance
Owner's Name(s)* Lantern Crest at Temecula, LLC
Address
800 Lantern Crest Way
Santee, CA 92071
Email Address Mgrant@mgrantcompanies.com
Phone Number 619-449-0249
*Note: If a corporation or LLC, provide information for principal partner or Agent for Service of
Process. If an HOA, provide information for the Board or property manager at time of project
closeout.
Submit to LDInspections@TemeculaCA.gov
2 STRUCTURAL BMP VERIFICATION INFORMATION
Template Date: August 14th, 2022 Preparation Date: _May 23, 2024_______
Stormwater Structural Pollutant Control & Hydromodification Control BMPs*
(List all from WQMP)
Description/Type of
Structural BMP
Plan
Sheet
# BMP ID#
Maintenance
Agreement
Recorded Doc
# Revisions
Biofiltration Basin 7 BMP #1
Pervious Pavers BMP #2
Filter Insert 8 BMP #3
Note: If this is a partial verification of Structural BMPs, provide a list and map denoting
Structural BMPs that have already been submitted, those for this submission, and those
anticipated in future submissions.
3 STRUCTURAL BMP VERIFICATION INFORMATION
Template Date: August 14th, 2022 Preparation Date: _May 23, 2024_______
Provide the following items for each Structural BMP selected
DMA ID No. Structural BMP ID No. Construction Plan Sheet No.
Structural BMP Verification Checklist: complete and include the Construction Verification and
Maintenance checklists from the associated fact sheets found in appendix E for selected
Structural BMP(s) along with the following items:
☐ Photograph of each completed Structural BMP.
☐ Photograph(s) of each Structural BMP during the construction process to illustrate
proper construction as described in the Structural BMP Fact sheets.
☐ Certificates of compliance for materials as required in the Structural BMP Fact sheets.
☐ Infiltration Tests as required in the Structural BMP Fact sheets.
☐ All DMAs draining to the structural BMP have been permanently stabilized and cleaned
of all trash and debris.
☐ All drainage systems draining to the structural BMP have been inspected and cleaned
and are free of trash and debris.
Purpose:
☐ Pre-treatment/forebay for another structural BMP
☐ Pollutant control only
☐ Combined pollutant control and hydromodification control
☐ Other (describe in discussion section below)
Who will be the final owner of this BMP?
☐ HOA ☐ Property Owner ☐ City
☐ Other (describe)
Who will maintain this BMP into perpetuity?
☐ HOA ☐ Property Owner ☐ City
☐ Other (describe)
Discussion (as needed):
By signing below, I certify that the Structural BMP(s) for this project have been constructed and
all BMPs are in substantial conformance with the approved plans and applicable regulations. I
understand the City reserves the right to inspect the above BMPs to verify compliance with the
approved plans and City Ordinances. Should it be determined that the BMPs were not
constructed to plan or code, corrective actions may be necessary before permits can be closed.
Professional Engineer's Printed Name:
Professional Engineer's Signed Name:
Date:
4 STRUCTURAL BMP VERIFICATION INFORMATION
Template Date: August 14th, 2022 Preparation Date: _May 23, 2024_______
City of Temecula Certification
City - OFFICIAL USE ONLY:
For City Inspector: Verification Package #: __________
City Inspector:
Date Project has/expects to close:
Date verification received from EOW:
By signing below, City Inspector concurs that every noted Structural BMP has been installed per
plan.
City Inspector’s Signature: _______________________________ Date:
For Land Development Staff:
Date Received from City Inspector:
Land Development Submittal Reviewer:
Land Development Reviewer concurs that the information provided for the following Structural
BMPs is acceptable to enter into the Structural BMP Maintenance verification inventory:
List acceptable Structural BMPs:
Land Development Reviewer’s Signature: Date: