The Central Coast Wetlands GIS Project employed aerial photograph interpretation, ground truthing, and field mapping to map wetlands and riparian areas within the Morro Bay Watershed.

Morro Bay Watershed 2003 Wetland Acreage
    Total Acreage: COMING SOON!
    Estuarine:
    Lacustrine:
    Palustrine:
    Riverine:
    Riparian:
Marine wetlands were not mapped as part of this project.

Aerial Photograph Interpretation & Ground Truthing
Wetlands were heads-up digitized using ArcView 8.3 and classified using 2003 one foot resolution photography provided by San Luis Obispo County. The minimum mapping unit is 0.25 acre.

The California Conservation Corps (Corps) ground truthed three pre-determined areas: lower Los Osos Creek, upper Los Osos Creek, and the estuarine/riverine transition in Chorro Creek. Problem areas were checked throughout the watershed where the Corps had access to the property. The Corps checked polygon delineation and classification.

Field Mapping
Field mapping was conducted by the Corps with a sub-meter global positioning system in three sites within the Morro Bay Watershed: the Chorro Ecological Reserve, Shark Inlet, and Walters Creek. Wetland polygons mapped in the field were classified and additionally attributed with the top 5 dominant plants and percent dominance vegetation within the polygon. The minimum mapping unit is 0.10 acre.

Wetland Definition
The CCWGIS used the California Coastal Commission definition of wetland when interpreting and mapping wetland habitats. This definition states that the habitat must meet one of the three wetland defining criteria, vegetation, hydrology, or soils, to be called a wetland. The official definition is taken from the California Coastal Act Section 30121 and is below:

"Wetland shall be defined as land where the water table is at, near, or above the land surface long enough to promote the formation of hydric soils or to support the growth of hydrophytes, and shall also include those types of wetlands where vegetation is lacking and soil is poorly developed or absent as a result of frequent and drastic fluctuations of surface water levels, wave action, water flow, turbidity or high concentrations of salts or other substances in the substrate. Such wetlands can be recognized by the presence of surface water or saturated substrate at some time during each year and their location within, or adjacent to, vegetated wetlands or deep-water habitats."

Classification System
Wetlands were classified using the Wetlands of the Central and Southern California Coast and Coastal Watersheds: A Methodology for their Classification and Description by Wayne Ferren, Peggy Fiedler, and Rob Leidy. All polygons were classified at the class level and first tier Hydrogeopmeorphic classifications were applied to the polygons.

Product
The final product of the mapping efforts is the Morro Bay Watershed Wetland and Riparian data set. This combines the aerial photograph interpretation, ground truthing, and field mapping efforts into one data set. Each polygon is attributed with the method used to delineate it. This data set can be viewed using the Morro Bay Watershed Pilot Interactive Mapping Service and may be downloaded from the GIS Data page.

Disclaimer
The Wetland and Riparian data set is not suitable for any regulatory purpose, and should not be the basis for any determination relating to the natural resource characteristics of any particular site or geographic area as well as impact assessment or mitigation. Please read the CCWGIS Disclaimer for more details.