Hellman Ranch Wetlands


SiteHellman Ranch

MapLos Alamitos USGS 7.5' quadrangle

LocationIn the City of Seal Beach, adjacent to the San Gabriel River Channel approximately 1 mile inland of the coast.

ContactsDave Bartlett (consultant to the major landowner) (714) 898-0600.

California Coastal Commission, (310) 590-5071.

Approximate Wetland Habitat Acreage 27.1 (described as degraded historic wetlands) scattered over approximately 190 ac. Also see Comments below.
5, 7, 3, 11
Approximate Historic AcreagePart of a complex at the mouth of the San Gabriel River that was 2,400 acres in 1894.
5, 6


Southern California Edison 7.9

State Lands Commission 3.4

Land Use DesignationLand Uses Designated in the Hellman Ranch Specific Plan adopted 1987 - Oil extraction; low, medium and high density residential, and parks and open space; zoning also includes a golf course.
5, 9
Onsite UseSummer 1996 - Transmission lines as well as oil extraction and storage facilities, associated trailers and office buildings, are located in the northern portion and margins of the property; wetland areas are substantially free of structures.
1, 2, 5, 7

A eucalyptus grove along the southern boundary of the property serves as a neighborhood park.

Historic UseThe site was used for farming and ranching until the 1930's when oil drilling began. The San Gabriel River was channelized 1961 - 1962, the Haynes Intake channel was built through a corner of the marsh in 1962; hydraulic dredge material from channel construction was deposited in the wetlands (nearly all historic wetlands were filled by 1969). The area was fenced in the late 80's to prevent off-road vehicle riding and other unpermitted recreational uses.
5, 9, 11
Adjacent UseUses of the adjacent and surrounding areas are primarily urban; a power plant water intake channel and the San Gabriel River channel lie to the west, a bluff topped by residential development creates the southern boundary, Seal Beach Blvd creates an eastern boundary with the Seal Beach Naval Weapons station beyond; to the north are a County flood control retention basin, a City yard and a business park.
5, 2
Adjacent Historic UseNative American use until the early 1800s; cattle ranching and farming gradually giving way to urbanization; oil extraction began in the 1930s. Channelization of the San Gabriel River and construction of the intake channel completed in the early 1960's.
6, 11

Tidal InfluenceA drainage channel (man-made), which is constricted by sediment deposits, several onsite culverts and a partially-functioning flapgate, provides severely muted tidal inflow.
8, 11
Watershed Area5,420 + acres

Tributaries and FlowTributary

N/A (Formerly, the San Gabriel River) N/A

Other SourcesStormwater runoff

GeneralSurface hydrocarbons in and adjacent to the area may affect the quality of runoff reaching the site. The lowest reach of the San Gabriel River is included in the 1995 draft list of impaired water bodies; standards for ammonia, fish tissue, water toxicity, lead, coliform bacteria, and algae were exceeded.
7, 4
Dissolved Oxygen (DO)1995, San Gabriel River - Profiles over ebb and flood tides in June and Sep. 1995 just downstream of the Haynes intake channel; concentrations throughout the water column were between 4 and 5 mg/l. Temperatures throughout the water column ranged 22-30 C.
Water SalinityTidal channel brackish, salinity comparable to that of the San Gabriel River (concentration not specified). 1980 - salinity of ponded water within the wetlands ranged from <0.5 to 40 ppm.
5, 3
SedimentNot specified


SoilSoil supporting wetlands are primarily dredge material, with slow to very slow infiltration rates which has been subjected to discing and off-road vehicle use. Soils in the vicinity of a pipeline crossing the site contain hydrocarbons.
HabitatAcres Vegetation
Tidal Channel3.21996 - common pickleweed along upper banks; algae, predominantly <i>Enteromorpha<i>, and a small amount of sea lettuce in the channel.
Salt Marsh (very little tidal influence) 14.91996 - Pickleweed, samphire, saltgrass, alkali weed, fivehook bassia, annual grasses, russian thistle* and cheeseweed* dominate species moving from lower to higher elevations. Also present in lower areas are heliotrope, fleshy jaumea and alkali heath.
Seasonal Ponds21996 - Mostly unvegetated, with occasional small patches of pickleweed and other unspecified species.
Alkaline Flats71996 - Habitat is mostly barren; small patches of pickleweed and other salt-tolerant species present.

Birds6 studies between 1987 and 1996 sighted a total of 89 species, 32 water-associated, 10 of special concern. One-day survey in August, 1995 sighted 20 species, 7 of which were water-associated, 2 of these having special status.
1, 11, 13
Fish1987 - mosquitofish observed. 1980 - <i>Tilapia<i>* and sailfin molly* were most numerous; striped mullet, staghorn sculpin, longjaw mudsucker and Ca killifish were also present. No information on survey method provided.
7, 3
Benthic Invertebrates1995 - California horn snail observed.
Insect1995 - Various dragonfly species observed.
Other Wildlife1987-1996 - 5 seperate surveys found evidence of 8 mammal species, including domestic dog*, coyote, red fox* in 1996. A 1995 survey for the Pacific pocket mouse found none. 1987, 1996 surveys found a total of 3 reptile species and 1 amphibian species.
1, 13
Special Status Species1987-1996 - Belding's Savannah sparrow, osprey, northern harrier, Cooper's hawk, snowy plover, Ca. gull, elegant tern, loggerhead shrike, yellow warbler, So. Ca. rufous-crowned sparrow.

Enhancement StatusAn amendment to the Specific Plan proposed Fall 1996 includes a reconfiguration of the wetlands (filling in some areas, restoration and creation in others) that would result in an overall increase of 3 acres. A permanent tidal connection would also be created and urban runoff would be rerouted to avoid the salt marsh. The amendment also includes a 90% reduction in allowable housing units.
Watershed ManagementNone identified.

PressureChannelization of the San Gabriel River and creation of the Haynes intake channel, limited tidal influence, elevations raised by fill, proximity to urban and industrial uses.
2, 5, 3,
CommentsThe 27.1 acres reported under Approximate Wetland Habitat Acreage reflects the definition used by the California Department of Fish and Game. It was the acreage used to describe wetland impacts in the 1996 proposal for amending the Specific Plan. A second delineation done for the proposed Specific Plan Amendment, according to the U. S. Army Corps of Engineers' definition, identified 23.2 acres of wetlands.

1Natural Resource Consultants. 1995.

Results of focused biological surveys to determine the status of the Calfornia least tern, the belding's Savannah sparrow, the Coastal California gnatcatcher and other sensitive species on the Hellman Ranch. Reports results of a one-day survey in August 1995 to update and verify information provided in a 1989 biological assessment of the site. None of the target species were found. The previous biological surveys and a printout of a Natural Diversity Data Base search are attached.

2LSA. 1995. Hellman Ranch Existing Wetlands. Blue line map.

Map depicting 1989 delineation of wetland habitat types overlaid on geographic features derived from a 1995 aerial photo. Figure prepared as part of the 1996 proposal for development.

3Radovich, Bob. 1980. An assessment of wetland resources within the City of Seal Beach south of the San Gabriel River. State of California Department of Fish and Game. 7 pp.

Report prepared in association with wetland mapping at Hellman Ranch, which was carried out by the Department of Fish and Game at the request of the Coastal Commission. It also provides an assessment of the site's biological value and recommendations for enhancement.

4Los Angeles Regional Water Quality Control Board. 1995. Draft 303(d) List.

A proposed list of waterbodies in the Los Angeles and Ventura County coastal watersheds that do not or are not expected to attain water quality standards after application of required technology-based controls. Specifies selected beneficial uses and criteria assessed, and the percentage of samples in which criteria were exceeded. It also identifies waterbodies for which previous assessments are no longer applicable. 303(d) lists are prepared as part of the Water Quality Assessment of the State's major waterbodies, and meet a requirement of section 303(d) of the federal Clean Water Act.

5Michael Brandman Associates, Inc. 1989. Draft supplemental environmental impact report Hellman Ranch Specific Plan. Approximately 150 pp. and technical appendices.

Prepared to evaluate the potential environmental impacts posed by an amendment to a previously adopted Specific Plan that adds restoration of 20 acres of onsite wetlands. The EIR focuses on the potential effects on wetlands and sensitive species and also evaluates three additional site plan alternatives. Wetland vegetation and monarch butterfly data are based on field surveys. Other existing condition data are summaries of information provided in the approved Specific Plan EIR.

6California Department of Fish and Game and U. S. Fish and Wildlife Service. 1976. The natural resources of Anaheim Bay. 103. pp. plus appendices.

This report summarizes the Anaheim Bay and its environs and resources. Physical features, history, land use, geology, and resource use are described. Appendices contain species lists for birds, mammals, and fish found at the bay. Prepared as part of a series documenting conditions of California's coastal wetlands.

7Michael Brandman Associates. 1987. Draft subsequent environmental impact report Hellman Ranch Specific Plan. Approximately 200 pp. and technical appendices. Evaluates potential impacts of amending the Hellman Specific Plan to provide for development of a residential/golf course complex. Biological data is based on field surveys and existing documentation. HEC - 1 model was used to assess potential flooding impacts, other analyses of water and geology are based on existing studies.

8LSA and Moffat and Nichol Engineers. 1990. Hellman property wetland restoration plan. Revised. 46 pp.

Details a restoration plan for 25.6 acres of wetlands to be carried out in conjunction with development of adjacent property. Grading, hydrology, planting and habitat elements are described. The hydrologic component predicted tidewater residence times to be achieved by grading and improving the tidal inlet. Includes statement of overall objectives and acreage goals for each habitat type. Monitoring program defines success criteria for plantings and identifies three reference wetlands that will provide the basis for performance standards for birds, fish, and benthic invertebrates.

9Bartlett, Dave. Dave Bartlett Associates. Personal communication. June 24, 1996.

10Dave Bartlett Associates. 1996. Hellman Ranch specific plan, Seal Beach, California. ~ 100 pp.

A proposal for amending the 1987 Specific Plan for Hellman Ranch. It describes the existing site conditions, assesses consistency with policies and regulations and lays out the plan implementation process. The amendment includes a reconfiguration of wetland distribution and types. The existing conditions summarizes wetland typess according to both Ca Department of Fish and Game and U.S. Army Corps of Engineers definitions, and reviews previous wetland determinations carried out on the site. Brief descriptions of wildlife use and vegetation types, based on field and literature surveys, are provided. Wetland restoration and creation plans identify goals for resulting systems, a conceptual grading plan, water sources, and species to be planted.

11Moffatt & Nichol Engineers, Coastal Resources Management and Michael Brandman Associates. 1996. Final conceptual wetland restoration plan for the Hellman Ranch Specific Plan. 53 pp.

Provides the technical basis for the wetlands restoration component of the proposed Hellman Ranch Specific Plan amendment. Identifies elevations for salt and freshwater marsh areas, describes hydraulic modeling and options for tidal connections, specifies requirements for site preparation and species to be planted, describes the construction sequence, maintenance requirements, target habitats, success criteria, the frequency and parameters to be monitored, and remedial procedures. The plan also describes existing wetland types according to the California Department of Fish and Game criteria, identifies plant species present and briefly evaluates the site's current potential as habitat for the Ca least tern and Belding's Savannah sparrow.

12MBC Applied Environmental Sciences. 1995. National Pollutant Discharge Elimination system 1995 receiving water monitoring report, Los Angeles Region. 110 pp and appendices.

Reports results of water quality monitoring offshore of So. California Edison Company's (SCE) and Los Angeles Department of Water and Power (LADWP) generating stations, to determine if Beneficial Uses of waters receiving Plant discharges were being maintained. Temperature, salinity, density, dissolved oxygen and hydrogen ion concentration were measured over ebb and flood tides in June and September 1995 in receiving waters of: Mandalay, Ormond Beach, Scattergood, El Segundo, Redondo, harbor, Long Beach, Haynes, and Alamitos Generating Stations. Results were compared with those of numerous previous thermal effect and NPDES studies. Salinity of the Haynes receiving water was not reported.

13Michael Brandman Associates. 1996. Biological technical report Hellman Ranch Specific Plan. 40 pp and appendix.

Describes biological resources of the 231-acre Hellman Ranch Specific Plan area, combining data from original field work and several previous field surveys. Original surveys describe vegetation, and bird, amphibian, reptile and mammal species present. The report also analyzes impacts to these resources expected from implementation of the proposed specific plan and identifies mitigation measures. Appendices include flora and fauna lists and vegetation, sensitive species and project impact maps.

14Coastal Resources Management and Chambers Group, Inc. 1996. Wetlands surveys on the Hellman Ranch property. ~ 20 pp and appendices.

This document consists of two reports; one verifying a previous wetland delineation done in 1989 according to state guidelines, the other presenting results of a delineation of wetlands under the jurisdiction of the U. S. Army Corps of Engineers. Both provide maps of vegetative communities. The appendices to the Corps delineation also includes field data sheets, a plant species list, and photographs of each of the communities identified.


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