Loading...
HomeMy WebLinkAbout3182; South Carlsbad Village Storm Drain Biological; South Carlsbad Village Storm Drain Biological; 1997-05-12DUDEK & ASSOCIATES Engineering, Environmental Sciences and Management Services Corporate Office: 605 Third Street Encinitas, California 92024 619.942.5147 Fax 619.632.0164 A California Corporation May 12, 1997 Mr. Doug Helming City of Carlsbad Engineering Department 2075 Las Palmas Drive Carlsbad, CA 92009 Re: South Carlsbad Village Storm Dear Mr. Helming: 1403-01 RECEIVED MAY I 3 1997 Reconnaissance Survey The South Carlsbad Village Storm Drain project involves construction of a backbone storm drain system extending from Agua Hedionda Lagoon northward approximately 5,500 feet along the alignment of the San Diego Northern Railroad right-of-way to Oak Avenue. The proposed storm drain project will consist of a underground pipe from Oak Avenue to the discharge at Agua Hedionda Lagoon. The discharge structure may incorporate a short section of concrete-lined channel to convey the flows to the lagoon. Energy dissipators will be installed at the outfall. No discharge of dredged and/or fill material to the lagoon is expected. Other portions of the storm drain system are located within existing development and contain no biological issues to address. A visit was made to the proposed project area on April 21, 1997 by DUDEK biologist Anita M. Hayworth, Ph.D. All areas proposed to be impacted by the South Carlsbad Storm Drain project were visited on foot. Areas of concern that may provide constraints to the project or require permitting from the resource agencies are discussed below. The vegetation within the open, dirt channel, as it travels from Oak Avenue to Village Avenue consists of grasses including brome (Bromus sp.) and wild oat (Avena barbata), western ragweed (Ambrosia psilostachya var. californica), wild radish (Raphanus sativus), red-stem storksbill (Erodium cicutarium), long-beaked storksbill (Erodium botrys), castor bean (Ricinis communis). This open channel is approximately 2700 feet long and is approximately 10 feet wide at the top of the channel. The channel is approximately 6 feet deep and in an area from Chestnut Avenue south approximately 300 feet, the channel contains water to a depth of a few inches. There is no wetland vegetation within the dirt channel. From Village Avenue south to the outfall to Agua Hedionda Lagoon, the storm drain is underground and consists of a 63-inch reinforced concrete pipe. The area above the concrete pipe is vegetated with non-native grasses (brome and wild oats), red-stem storksbill, long- beaked storksbill, and wild radish. The outfall from the existing pipe to Agua Hedionda Lagoon consists of a concrete-lined channel, approximately 50 feet in length. There is no wetland vegetation within the concrete channel. Mr. Doug Helming Re: South Carlsbad Village Storm Drain Biological Reconnaissance Survey 12 May 1997 Pg.2 The proposed storm drain from Agua Hedionda to Oak Avenue consists of replacement of the existing dirt channel and possibly replacement of the existing pipe with the new line. One section, the dirt channel from Oak Avenue to Village Avenue, to be impacted by the proposed project would be considered "waters" of the U.S. according to the U.S. Army Corps of Engineers (ACOE). None of the exposed storm drain channel would be considered wetlands by the California Department of Fish and Game (CDFG). In order to proceed with impacting the areas considered "waters of the U.S.", a delineation of the waters is required. The delineation follows the 1987 Corps of Engineers Wetlands Delineation Manual. The delineation results in a stand-alone report that characterizes the waters, discusses the wetland functions and values, which, in this case, are none, and determines the amount to be impacted by the project. Once the delineation is prepared, the document is submitted to the ACOE for review. Permits that may be required by the resource agencies for impacts to the waters of the U.S. include a Section 404 permit from the ACOE. Typically, a Section 401 Permit or Waiver is required from the Regional Water Quality Control Board (for water quality certification). A Section 1603 Streambed Alteration Agreement would not be required from the CDFG. The ACOE Section 404 permit application includes a standard application along with the submittal of the wetland delineation report described above. The ACOE reviews the application for completeness and either grants a Nationwide 404 permit or requires an Individual permit within 20 days. Most likely the impact to the existing storm drain channel could be covered by one of the ACOE Nationwide Permits which pre-authorize the impacts to waters. In order for a Nationwide Permit to be used the impact must be less than one- third of an acre. The Section 401 permit application includes a standard application, a $500 fee, and a letter that describes the activity, impact and measures taken to avoid reducing water quality. Please feel free to contact me at (760) 942-5147 with questions or if you require additional information. Very truly yours, DUDEK & ASSOCIATES, INC. •fL Anita M. Hayworty Ph.D. Ecologist/Senior Project Manager