HomeMy WebLinkAboutEIA 97-07; DRAINAGE CHANNEL & DESILTATIONI; Environmental Impact Report (EIR)DICK JACOBS ASSOCIATES
PUBLIC FACILITY HNA'ICIIVG • MUl>lfC[P4LCONSULTI'IG
RICHARD K. JACOBS, PE.
PRINCIPAL
1736 BLACKBIRD CiRCLE
CARLSBAD. CAUFORN:" 92009
(619) 929-Q135
FAX (619) 929-0916
1 ) APPLICATIONS APPLIED FOR:
0 Administrative Permit -2nd
Dwelling Unit
0 Administrative Variance
0 Coastal Development Permit
0 Conditional Use Permit
o Condominium Permit
~vironmental Impact
0
0
0
0
0
0
2)
3)
4)
Assessment
General Plan Amendment
Hillside Development Permit
Local Coastal Plan Amendment
Master Plan
Non-Residential Planned
Development
Planned Development Permit
CITY OF CARLSBAD
LAND USE REVIEW APPLICATION
(CHECK BOXES)
;;
(FOR DEPARTMENT
USE ONLY)
17-~7
. . .
TELEPHONE 4Si'-II~/ as-z..
(FOR DEPARTMENT
USE ONLY)
0 Planned Industrial Permit
0 Planning Commission
Determination
0 Precise Development Plan
0 Redevelopment Permit
0 Site Development Plan
D Special Use Permit
D Specific Plan
0 TeAtative Pareel Map
ObtaIn from Engineering Department
D Tentative Tract Map
D Variance
D Zone Change
D List other applications not
specified
6) APPLICANT NAME (Print or Type)
/C#:-'J~~.J S.sOC/~ f,;~
MAILING ADDRESS
3' 75/~~~'rj Ctrc/-<.-
ZIP TELEPHONE
I CERTIFY THAT I AM TH LEGAL OWNER AND THAT ALL THE ABOVE
INFORMATION IS TRUE AND CORRECT TO THE BEST OF MY
KNOWLEDGE.
I CERTIFY THAT I AM THE LEGAL REPRESENTATIVE OF THE
OWNER AND THAT ALL THE ABOVE INFORMATION IS TRUE AND
COR TO E BEST OF MY KNOWLE~
SIGNATURE DATE DATE
7) BRIEF LEGAL DESCRIPTION
NOTE: . A PROPOSED PRo.JECT REQUIRING MULTIPLE APPLICAnONS BE AlED. MUST BE SUBMITTED PRIOR TO 3:30 P.M.
A PROPOSED PROJECT REQUIRING ONLY ONE APPUCAnON BE ALED. MUST BE SUBMITTED PRIOR TO 4:00 P.M.
Form 16 PAGE 1 0. ~
8)
a7 I /J ~ L I II ac7 e7~-ILI.:t-
LOCATION OF PROJECT: r~~' ~//ltJ,,'''IT89tU''''~-P'J.(l1t./t?,.r~.
STREET ADDRESS •
ON THE I SIDE OF
(NORTH. SOUTH, EAST. WEST)
BETWEEN A J fj I 'AND
(NAME OF STRFf-iiI ~
(NAME OF STREET)
(NAME OF STREET)
/,:------.
9) LOCAL FACILITIES MANAGEMENT ZONE I L-_____ ----l
10) PROPOSED NUMBER OF LOTS D 11) NUMBER OF EXISTING D 12) PR ED NUMBER OF
RESIDENTIAL UNITS " ESIDENTIAL UNITS ~~
13) TYPE OF SUBDIVISION D 14) PROPOSED IND OFFIC.5!~ 15} PROPOSED COMM
SQUARE FOOTAGE-/ '~ SQUARE FOOTAGE --/
16) PERCENTAGE OF PROPOSED D 17~PRQFT :eSro~NCREASE IN D 18) PROPOSED SEWER
PROJECT IN OPEN SPACE ____ -A'DT USAGE IN EDU
f --19) GROSS SITE ACREAGE ,/,0//-20)
//'
/
EXISTING GENERAL
PLAN
.-// ... ~
22) EXISTI/' D 23) PROPOSED ZONING
D 21) PROPOSED GENERAL
PLAN DESIGNATION
D
D
D
D
D
24) IN THE PROCESS OF REVIEWING THIS APPLICATION IT MAY BE NECESSARY FOR MEMBERS OF CITY
STAFF, PLANNING COMMISSIONERS, DESIGN REVIEW BOARD MEMEBERS OR CITY COUNCIL MEMBERS
TO INSPECT AND ENTER THE PROPERTY THAT IS THE SUBJECT OF THIS APPLICATION. I/wE CONSENT
TO ENTRY FOR THIS PURPOSE
!j;/;t
FOR CITY USE ONLY
FEE COMPUTATION
APPLICATION TYPE
,
//'
/
/
/'
TOTAL FEE REQUIRED
DATE FEE PAID
Form 16
FEE REQUIRED
,'.--.-' ,-
fll
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)1'
RECEIVED
SEP 1 9 1997
CITY OF CARLSBAD
PLANNING DEPT
DATE STAMP APPLICATION RECEIVED
RECEIVED BY:
I ~
RECEIPT NO.
PAGE 2 OF 2
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DICK JACOBS ASSOCIATES
PUBLIC FACILITY FINANCING • MUNICIPALCONSULTlNG
August 13~ 1997
Mr. Walter H. Brown, P.E.
Principal Civil Engineer
City of Carlsbad Engineering Department
2075 Las Palmas Drive
Carlsb~ CA 92009-1576
Re: Project Scope Report
Rancho Carlsbad Channel and Basin Project
Project No. 3338
Dear Walter:
This report constitutes the Project Scope Report for Project No. 3338~ the Rancho Carlsbad Channel
and Basin Project. The report sunnnarizes the project purpose, issues, costs and funding sources and
provides recommendations on the manner in which to proceed with the selection and ultimate
construction of a permanent solution for drainage and sediment in the basin .
The project is located north and east ofEl Camino Real at Rancho Carlsbad Drive in the vicinity of
the Rancho Carlsbad Mobile Home Park, an existing 108 acre~ 504 space mobile home parle The
confluence of the Agua Hedionda Creek and the Lake Calavera Creek is located within the Park
boundary. The various features that comprise the project are depicted on City of Carlsbad 100 scale
orthophoto maps accompanied by photos of existing conditions of the site. These maps and photos
are considered a part of this report.
Badcgrnund and Pm:poK
The need for the project evolved as a result of the following:
1. The adopted ''Master Drainage and Storm Water Quality Management Plan" ca1Is for the
construction ofFacility BJ and Facility BJB. Facility BJB is designated as a "sedimentation
basin northeast offuture Cannon Road and College Boulevard". Facility BJ consists in part
of "an earthen channel ... to cany drainage to Agua Hedionda Creek" from the
aforementioned sedimentation basin. This consists of approximately 3.,400 feet of
improvement 'to Lake CaIavera Creek located on the western boundary of the Mobile
Home Park and east oftbe alignment offuture Camon Road. This is designated as Project
1736 BLACKBIRD C:RCLE· CARL~(,AD, CAUFORNIA 92009-5008
(619) 929-0135· FAX (619) 929-0916
No. 33381 in the 1997-98 Capital Improvement Program.
2. The owners of the Rancho Carlsbad Mobile Home Park have applied for a Mobile Home
Park Permit and a Tentative Parcel Map for conversion of the existing 504 space
residential mobile home park to a resident own~ airspace condominium mobile home
park. It was determined that certain drainage faciIities were inadequate. As a condition of
approval, improvements to the Agua Hedionda Creek through the Mobile Home Park will
be required as identified in the amendment to the City of Carlsbad Master Drainage Plan
as approved by the City Council on December 3, 1996 (Resolution No. 96-403).
The purpose of the project may be defined as follows:
1. To provide for safe conveyance of runoff from future development in accordance with the
Master Drainage Plan accomplished through preparation of plans, specifications and
estimates for construction of sedimentation/detention basin BJB (Master Drainage Plan)
and improvements to Lake CaIavera Creek from basin BJB to El Camino Real bridge.
2. To prepare a solution for the safe conveyance of the Agua Hedionda Creek 100 year flood
flow through the Rancho Carlsbad Mobile Home P~ and to prepare plans, specifications
and estimates for ultimate improvements to Agua Hedionda Creek.
Project Characteristics and Issues
The Lake Calavera Creek basin and the Agua Hedionda Creek basin have been the subject of a series
of studies and reports prepared by Dr. Howard Chang, Ph.D., P .E. dating from 1989. The overall
PUIpOse of the studies has been to determine the 100 year flood discharges for the two creeks under
ultimate development conditions and to determine the flood plain boundary and the floodway
delineation for Agua Hedionda Creek. In addition, recommendations have been presented for solving
the inadequate drainage situation along each of the creeks through the Rancho Carlsbad Mobile
Home Park. The Lake Calavera Creek extends for a distance of approximately 3,400 feet on the
western boundaIy of the mobile home park. The Agua Hedionda Creek extends through the mobile
home park from the bridge at EI Camino Real to the bridge at Rancho Carlsbad Drive, a distance of
approximately 2,900 feet.
The two basins comprise a total drainage area of 24.09 square miles, Lake Calavera Creek basin
amounting to 5.90 square miles and Agua Hedionda Creek basin the remaining 18.19 square miles.
Following is a tabulation of the Chang studies together with a summary of the results of each:
-Hydrological Study.for Northeastem Carlsbad, July 1989
-Established 100 year Q's as follows:
-Lake Cal.vera Creek
-Upstream from confluence with Agua Hedionda Creek -1,740 cfs
-Agua Hedionda Creek
2
-Upstream. from confluence with Lake Calavera Creek -8~080 cfs
-Just downstream from confluence with Lake Calavera Creek -9~848 cfs
-Just downstream from EI Camino Real bridge -9~910 cfs
--Recommended restoration of Lake Calavera Creek by dredging methods
-Determined that Rancho Carlsbad Bridge on Agua Hedionda Creek
insufficient to pass 100 year flood
-Floodplain Boundary and F/oodway Delineation for Agua Hedionda Creek~ Sept
1991
--Determined floodplain and floodway lines for Agua Hedionda Creek from EI
Camino Real bridge to 1.5 miles east of Mobile Home Park boundary
-Detennined that the channel profile for the proposed College Avenue bridge and an
access road bridge upstream. had no effect on the water surface elevations for the
upstream properties
-Flooding Issues Related to Agua Hedionda Creek/or Rancho Carlsbad Mobile Home
Park, May 1996
-Delineated boundary of 100 year flood plain through mobile home park on Manitou
map
-Indicated capacity of existing Agua Hedionda Creek through mobile home park at
about 6,500 cfs or 50 year storm
-Indicated maxinmm volume of detention on goff course to the east of mobile home
park = 25 acre feet--detention volume need to reduce flow to 6,500 cfs is 96 acre feet
-Flooding Issues Related to Agua Hedionda Creek/or Rancho Carlsbad Mobile Home
Park~ June 1996
-Examined 4 structural and 1 non-structural alternative for solving flooding
problems:
Stmctural
1. On site detention
2. Diversion to the south to El Camino Real
3. Diversion to the north to Lake Calavera Creek
4. Levees for Agua Hedionda Creek thru Mobile Home Park
Non-Structural
1. Advanced flood warning system
-Recommended priority of alternatives:
1. Advanced flood warning system
2. Diversion to the north to Lake Calavera Creek
3. Levees for Agua Hedionda Creek thru Mobile Home Park
In addition to the Chang hydrology and hydraulic studies, FEMA has prepared a study for the Agua
Hedionda Creek. The FEMA study resulted in water surl8ce elevations ranging from 2 to 4 feet above
3
the Chang elevations.
Project Needs
The project requires a permanent solution to the drainage and sediment problems that have and will
continue to affect the two existing creeks with the resultant impacts to the Rancho Carlsbad Mobile
Home Park. A solution needs to be formulated and put in place prior to extensive development of the
basin upstream.
Given the difference in results between the Chang studies and the FEMA study, the first task will be
to review and comment on the hydrology and hydraulic analyses to arrive at a level of comfort with
respect to this data in order to move forward with the development of design alternatives.
Clearly 7 the Chang studies on potential solutions to the Agua Hedionda Creek flooding problems
were conceptual in nature. These analyses as well as other potential solutions will require more
detailed study regarding function, environmental consequences and both capital and maintenance
costs. There is the potential for construction of upstream detention facilities on the Agua Hedionda
Creek. There is also the potential for formulating a regional or basin plan for Agua Hedionda Creek
rather than a project by project plan. Given the number of development applications upstream, there
may be a window of opportunity to achieve a basin plan that would be looked on more favorably by
the resource agencies (Corps of Engineers, Fish and Game, etc) that will be permitting each of the
proposed projects.
Lake Calavera Creek on the western boundary of the mobile home park is restricted and silt laden in
its present state. The proposed sedimentation basin north and east of the park could also serve as a
detention basin for control offiow through the park The basin needs to be sited in relation to the final
alignment of the intersection of College and Cannon in this area. A final solution will evolve only after
detailed study of alternatives regarding function, environmental consequences and both capital and
maintenance costs.
RigbtofWay
Easements for drainage, access and construction of Lake Calavera Creek and Agua Hedionda Creek
through the mobile home park will be conveyed to the City. Other potential right of way needs
determined after evaluation and selection of alternatives would include the following:
--Right of way for sedimentation basin north and east of the mobile home park
-Right of way for additional conveyance capacity for Lake Calavera Creek
-Right of way for possible detention facilities along Agua Hedionda Creek.
-Right of way for possible diversion channels along Agua Hedionda Creek.
Environmental
The environmental analysis will be focused on impacts to the riparian habitat. Depending on the
disturbance to the wetland areas based on the final design solution, permits will be required from the
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various state and federal resource agencies for work that impacts either one of the creeks. Likely
permits required will include a 1601 Permit from the state Department ofFish and Game and a 404
Permit from the US Army Corps of Engineers.
Cost Estimates and Funding Sources
Until a final design solution for the project has been investigated and approved, it is difficult to assign
a cost estimate to the project. The current 1997-98 Capital Improvement Project Budget has $1.12
million appropriated from Planned Local Drainage Fees.
The City has an agreement with the Rancho Carlsbad Mobile Home Park owners for payment of
$318,000 for flood control improvements outlined in the aforementioned amendment to the Master
Drainage Plan. The terms of this agreement allow for payment over a ten year period.
In addition, an application was submitted in June 1997 to the California Office of Emergency Services
for a FEMA Hazard Mitigation Grant for this project. The requested amount is approximately
$540,000. As of August 1997. FEMA, in reviewing the application, has determined that the City is
an eligible applicant and is requesting additional information.
Recommendations
There is a defined need to develop design alternatives leading to selection and ultimate construction
of a permanent solution for the drainage inadequacies and sediment problems in both the Lake
Calavera Creek and Agua Hedionda Creek through the mobile home park. Each of the conceived
design alternatives will result in varying degrees of environmental consequences that should be
addressed up front so that only viable alternatives are analyzed.
Therefore, it is recommended that a concurrent selection process be initiated for retaining both a
Civil/Hydraulic consultant and an Environmental consultant to work together in the development of
a final concept for the basin. Upon approval of the preferred alternative, the consultants would be
directed to prepare the final plans, specifications and estimates and the finaI EIR.
Please call with any questions on the content of this report. I appreciate the opportunity to be of
service.
Yours truly,
DICK JACOBS ASSOCIATES
Richard K. Jacobs.
Principal
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