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Phone # Cell Phone #
Mailing Address City/St/Zip
Email Address Receive Project Updates by Email - Yes No Architect/Designer
Phone # Cell Phone #
Mailing Address City/St/Zip
Email Address
State License # Receive Project Updates by Email - Yes No Authorized Agent Phone #
Cell Phone # Mailing Address
City/St/Zip Email Address
State License # Receive Project Updates by Email - Yes No Please note that the applicant/agent will receive a U.S. Postal Service or Email notification of project updates, such as plan check results. In addition, all other development team members listed on this page will also receive project updates by email, including plan check results, unless indicated otherwise.
This will improve communication with the applicant’s team during the entitlement process.
CITY OF LAGUNA BEACH • DEPARTMENT OF COMMUNITY DEVELOPMENT • 505 FOREST AVENUE • LAGUNA BEACH • CALIFORNIA • 92651
DEVELOPMENT REVIEW APPLICATION
PROJECT LOCATION ADDRESS
LOT SIZE _______________________________ ASSESSOR’S PARCEL NO.
DESCRIBE IN DETAIL SCOPE OF WORK
Attachment 3
27 600 Buena Vista Way 1.52 acres (66,211.2 sf) 641-373-43 Request by property owner to delete drainage course from the environmentally sensitive areas map (LBMC sections 25.50.030, 25.05.065, 25.07.026). The argument for deletion is set forth in Attachment A to this Application, and its Exhibits 1-8. David Cozzens and Susan Heystee c/o Laidlaw Schultz Architects (see below) Craig Schultz, AIA, Laidlaw Schultz Architects (949) 645-9982 3111 2nd Avenue, #1 Corona Del Mar, CA 92625 [email protected] Laurence P. Nokes, Esq. (949) 235-3060 410 Broadway Street, Suite 200 Laguna Beach, CA 92651 [email protected] 28 ATTACHMENT A to Development Review Application | Page 1
ATTACHMENT A
TO APPLICATION TO REMOVE WATERCOURSE FROM MAP
600 Buena Vista Way, Laguna Beach, California
This Development Review Application seeks removal of a mapped watercourse on the 600 Buena Vista Way property. The watercourse, as mapped, clearly serves no functional, scenic or ecological purpose. The watercourse originates at 648 Canyon View Drive and descends over the 600 Buena Vista Way property, terminating at the Temple Hills cul-de-sac, next to the property at 528 Temple Hills Drive. (Exhibit 1 – City GIS Map.) Attached is a Hydrology Study prepared by Toal Engineering on November 10, 2024.
This report was submitted to the City in support of the December 12, 2024 DRB application, which was approved 5-0. The report is resubmitted with this Application. (Exhibit 2 – Hydrology Study.) A Cultural Resource Study was prepared for the project by PSOMAS on October 16, 2018. (Exhibit 3.) No cultural or ecological resources were found to exist on the site. LSA prepared a Vegetation Map and Biological Resources Review on October 21, 2024. (Exhibit 4.) As seen in the report, the area of the “watercourse” is characterized as “Developed or Disturbed,” “Ornamental Plantings,” “Ruderal,” and “Toyon-Sumac Chaparral”. According to the report, “Ruderal areas generally contain a high percentage of bare ground and occur at any site that has been disturbed by natural or human causes. Areas classified as ruderal within the project site consist of disturbed areas that appear to be maintained for fuel modification purposes.”
While this “watercourse” appears on the City’s environmentally sensitive areas map, this designated drainage conveyance is, and has been for decades, nothing but a dry gulch. This is evidenced by the attached studies, the development history of 528 Temple Hills Drive, and the development history of 600 Buena Vista Way.
528 Temple Hills Drive Development
While proposing development of a new project at 528 Temple Hills Drive on November 30, 2007, Mark Singer applied for a variance to encroach into the watercourse setback, arguing that the watercourse was “inactive.” The drawings attached to the application show a wall at the bottom of the watercourse that transects the watercourse. (Exhibit 5 – Mark Singer Letter dated November 30, 2007.) Singer’s variance justifications identify a wall adjacent to Temple Hills Drive, and clearly show the wall located across the watercourse and on the 600 Buena Vista Way property. On March 13, 2008, the DRB unanimously approved the application and granted the requested variance, approving this wall across the watercourse and on the 600 Buena Vista Way property as part of the 528 Temple Hills Drive application. This was done without notice to, or permission or consent of, the 600 Buena Vista Way owners. 29 ATTACHMENT A to Development Review Application | Page 2 In considering the development application for 528 Temple Hills Drive, this “watercourse” was never considered “significant” or “functional” or “scenic”, or of any ecological purpose, by the Planning Staff or the discretionary Design Review Board. 600 Buena Vista Way Development
Design Review for 600 Buena Vista Way was approved in March 2021. A revision brought the project back to the DRB in December 2024, necessitating the preparation of the Hydrology Study (attached as Exhibit 2). When the planning application was made in 2004 by a prior owner of 600 Buena Vista Way, no hydrology study was required by Staff. (Exhibit 6 - Nancy Csira’s Zoning Plan Check Checklist dated March 30, 2004.) When assessing a proposed fire turnaround that was to be constructed within the mapped watercourse, Steve May, Director of Public Works, determined that the street turnaround “…within a watercourse” was to be allowed as it would “…enhance public safety.” (Exhibit 7 – Memo from Steve May dated September 8, 2004.)
A look at the City GIS Map of the “watercourse” and inspection of the site tell the story.
The driveway leading from the end of Buena Vista Way to the building pad for 600 Buena Vista Way cuts directly across the “watercourse”. This same driveway has been in place for decades.
There is no drainpipe under the driveway that conveys water under the driveway from the upper section of the watercourse on 648 Canyon View Drive, to the lower section of the “watercourse” on 641 Canyon View (now 600 Buena Vista Way). There are no erosion marks across this dirt road at the “watercourse”, clearly proving that Mark Singer was correct, back in 2006, when he noted that the watercourse is “inactive.”
Area Development
The properties on Temple Hills Drive and Canyon View Drive have been developed over the decades, and water from developed parcels has obviously been dealt with in the development of those parcels. Drainage that flowed at one time through watercourses has since been picked up through site drainage and vectored into approved drainage through the development of engineered site plans. Drainage that, at one point, may have flowed through this dry gulch, now flows down Canyon View Drive and Buena Vista Way.
There is simply no justification to retain this relic on the City’s environmental map. It serves no “distinct functional, scenic or ecological purpose.” As an inactive relic of a former drainage course, the mapped watercourse serves no hydrological purpose whatsoever and should be removed from the map.
30 EXHIBIT 1
31 32
EXHIBIT 2
33 HYDROLOGY STUDY
600 Buena Vista Way
Parcel 2, L.L.A. 03-03
Laguna Beach, California
Laguna Beach Plan Check No.
Prepared for:
Susan Heystee & David Cozzens
c/o Laidlaw Schultz Architects
3111 Second Avenue
Corona Del Mar, CA 92625
Tel: 949-645-9982
Prepared by:
Toal Engineering, Inc.
139 Avenida Navarro
San Clemente, CA 92672
Tel: (949) 492-8586
Fax: (949) 498-8625
November 10, 2024
………………………………………………………
Caleb Rios R.C.E. 57587
JN 16209
34 Table of Contents
1.0 PURPOSE ........................................................................................................................... 1
2.0 DESCRIPTION OF SITE ................................................................................................... 1
3.0 EXISTING DRAINAGE .................................................................................................... 1
4.0 PROPOSED DEVELOPMENT.......................................................................................... 1
5.0 PROPOSED DRAINAGE .................................................................................................. 1
6.0 FLOW ANALYSIS METHODOLOGY ............................................................................ 2
6.1 Rational Method For 100 Year Storm .................................................................................. 2
6.2 Manning’s Equation for Pipe Capacity ................................................................................. 2
7.0 FLOW RESULTS AND ANALYSIS ................................................................................ 2
8.0 CONCLUSIONS................................................................................................................. 2 APPENDIX A ................................................................................................................................. 1 APPENDIX B ................................................................................................................................. 4 APPENDIX C ................................................................................................................................. 5 35 1
1.0 PURPOSE
This report has been prepared to accompany the Precise Grading and Drainage Plan prepared by Toal Engineering, Inc. for the proposed new residence at 600 Buena Vista Way and to demonstrate that the proposed drainage system will accommodate the 100-year storm runoff across the project site. This report also intends to show that the existing significant drainage course on the project site has no upstream tributary area and, therefore, should not need to be designated as a watercourse going forward.
2.0 DESCRIPTION OF SITE
The existing developed polygonal-shaped 1.516-acre (66,044 sq. ft.) lot consists of a developed pad with partially constructed retaining walls. The property is at the northerly terminus of Buena Vista Way. It is bordered on the north and east by natural slopes, and on the south and southwest by existing homes. Below the project site to the west is the northerly terminus of the Temple Hills Drive cul-de-sac.
See Figure 1 for a depiction of the project location and Figure 2 for an aerial photograph of the site (Appendix A).
3.0 EXISTING DRAINAGE
Runoff from the hill above the pad, as well as the pad, sheet flows in a southerly direction towards Buena Vista Way. All runoff from the sloped portion of the site flows to the west to Temple Hills Drive.
4.0 PROPOSED DEVELOPMENT
The project consists of the construction of a new single family residence with appurtenant hardscape, walls, a swimming pool, and landscape areas. Along each side of the house are concrete walkways and patios, along with small planters. The project area is 23,135 sq. ft. (0.531 ac). The total area of the property is 66,044 sq. ft (1.516 ac), with 42,909 sq. ft. (0.985 ac) remaining untouched by the development.
5.0 PROPOSED DRAINAGE
The Hardscape improvements on the project site, including the building footprint, total approximately 14,400 square feet. Where possible, hardscape areas direct flows into adjacent planters to promote infiltration into the native soils and provide pre-treatment. Once all run-off is collected in the drainage system it will flow into an MWS unit for treatment prior to discharge.
All runoff from the project site, as well as runoff from the sites above, will be collected in 8” and 10” storm drain pipes and discharged to the street at Temple Hills Drive. 36 2
6.0 FLOW ANALYSIS METHODOLOGY
6.1 Rational Method For 100 Year Storm
For post-project conditions, Toal Engineering, Inc. performed a rational method hydrologic analysis based on Orange County Hydrology Manual (OCHM) Section D to estimate the peak runoff quantities discharged from the site. The site time of concentration was conservatively estimated to be 5 minutes, which is the minimum allowed by the OCHM.
6.2 Manning’s Equation for Pipe Capacity
The full flow capacity of proposed drain lines was estimated using the Manning Equation and the details and assumptions can be found in Appendix B.
Calculations are shown in Appendix B. The Drainage Map in Appendix C graphically depicts the project watershed and data relevant to the runoff calculations.
7.0 FLOW RESULTS AND ANALYSIS
Our hydrologic and hydraulic analysis of the site yielded the following results:
Table 1. 100-Yr Peak Runoff.
Subarea Q100 (cfs)
A 4.62
B 1.83
C 3.76
Total 10.21
Table 2. Pipe Capacity Verification.
Pipe Size (in) Q100 (cfs) Sf required S0 proposed So > Sf 1 8 4.62 0.1247 0.150 Yes
2 8 1.83 0.0195 0.020 Yes
3 8 3.76 0.0827 0.100 Yes
4 10 10.21 0.1852 0.280 Yes
Table 2 shows for all pipes the proposed pipe slope is greater than the friction slope required to discharge the design flow rate. This is a conservative comparison since the available friction slope is greater than the proposed pipe slope.
8.0 CONCLUSIONS
The proposed storm drain system has sufficient capacity to convey estimated peak discharges to the community storm drain system.
37 3
Further, the proposed storm drain system will fully accommodate all runoff upstream of the existing drainage course, and discharge it to the street below (Temple Hills). 38 APPENDIX A
Vicinity Map and Aerial Image
39 2
Figure 1. Vicinity Map
maps.google.com
SITE
40 3
Figure 2. Aerial Image
maps.google.com
SITE
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