HomeMy WebLinkAbout3338; Agua Hedionda & Calavera Creek Dredging; Agua Hedionda & Calavera Creek Wetland; 2005-10-01WETLAND DETERMINATION AND DELINEATION REPORT
FOR AGUA HEDlONDA AND CALAVERA CREEKS
Prepared for:
City of Carlsbad
Department of Public Works-Engineering
1 63 5 Faraday Avenue
Carlsbad, CA 92008-73 I4
Phone: 760.602.2720
Fax: 760.602.8562
Contact: David Hauser
EDAW, Inc.
1420 Kettner Boulevard, Suite 620
San Diego, CA 921 0 1
Phone: 6 1 9.233.1454
Fax: 6 19,233.0952
Contact: John Messina
October 2005
LIST OF FIGURES
Table -
Regional Location Map ....................~......~~.......................................................................... 2
................................................................................................................. Project Location 3
Agua Hedionda and Calavera Creeks U.S. Army Corps of Engineers and
California Department of Fish and Game Jurisdictional Areas ........................................ 13
Agua Hedionda Creek (2002 Study Area) ................... ........ ........................................ 1 5
Willow Riparian Forest along Agua Hedionda Creek between the El Camino
........................................................................................ Real and Cannon Road Bridges 16
Wetlands and Unvegetated Waters of the U. S . along Calavera Creek ............................. 18
Wetlands within Detention Basin BJB and Unvegetated Waters of the U.S.
along Calavera Creek at the Culvert Outlet from Detention Basin BJB ........................ ... 19
LIST OF TABLES
Page
ACOE and CDFG Jurisdictional Waters, Wetlands, and Riparian Habitat. ..................... 1 1
Page ii Agua Hedionda and Calavera Creeks Wetland Determination and Delineation Report
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PROJECT DESCRIPTION AND LOCATION
The City of Carlsbad proposes to dredge and improve portions of the Agua Hedionda and
Calavera creek channels located within and adjacent to the Rancho Carlsbad Mobile Home Park
(RCMHP). The project is needed to restore 100-year flood protection to as many RCMHP
residents as feasible. Currently, more than 300 lots would be inundated by a 100-year storm
event. The proposed project involves dredging the Agua Hedionda and Calavera creek channels,
removing or modifying the existing weir wall structure at the Detention Basin BJB, modifying
the outlet to the Detention Basin BIB culvert, modifying existing piers under the Cannon Road
and El Camino Real bridges, stabilizing the channel and bank of Calavera Creek, and mitigating
for impacts to existing environmental resources.
The project is located in the northeast section of the city of Carlsbad, along Agua Hedionda and
Calavera creeks, immediately west of the intersection of El Camino Real and Cannon Road, to
approximately 3,000 feet to the east. The study area includes Agua Hedionda Creek, from just to
the north of the Cannon Road Bridge to Rancho Carlsbad Drive to the east. The study area
includes Calavera Creek hrn its confluence with Agua Hedionda Creek to the Detention Basin
BJB, east of the intersection of College Boulevard and Won Road (Figures 1 and 2).
METHODOLOGY
On August 26, 2005, EDAW botanist John Messina conducted a routine wetland and waters
determination and delineation of Agua Hedionda and Calavera meks as well as an existing
storm water detention basin (Detention Basin BJB). This determination and delineation was
conducted pursuant to Section D Subsection 2 "Onsite Inspections for Routine Determinations
for Areas Equal to or Less than 5 Acres in Size" of the U.S. Army Corps of Engineers (ACOE)
Wetland Delineation Manual (Environmental Laboratory 1987). A wetland determination and
delineation had previously been prepared by RECON (2002) for that portion of Agua Hdonda
Creek to the east of the El Camino Real Bridge. RECON'S delineation also included the
confluence of Agua Hedionda and Calavera creeks. For these areas EDAW verified the previous
wetland determination and delineation. This verification consisted of a survey of the area
delineated by RECON to observe whether the existing conditions of Agua Hedionda Creek had
substantially changed since the time of the RECON report. A formal routine determination and
delineation was not conducted for the area encompassed by the RECON report. For a detailed
description of the methodology used for the previous delineation, refer to the RECON report
(2002).
Agua Hsdionda and Calavera Creeks Wetland Determination and Delineation Report Page 1
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