The Carneros Watershed
The Carneros Creek Watershed is located in the Central Coast of California, in Monterey County. The Carneros Watershed is part of the larger Elkhorn Slough Watershed, and Carneros Creek (not to be confused with the Carneros Creek in Napa, California) is the main fresh water tributary to Elkhorn Slough.
Contents
Location, Size and Climate
The Carneros Creek Watershed is located within the limits of Monterey County in the California central coast. It comprises the towns of Aromas, Las Lomas, and parts of Prunedale, and it covers approximately 70 km². The area has a Mediterranean climate [2], with mild summers with temperatures in the 60's, and cool, mild, winters with temperatures in the 50's [3] . The warmest month of the year is September, and the coldest is December, with average maximum and minimum temperatures of 73.7°F and 38.1°F respectively. The winter months are wetter than the summer months, and the wettest month is January; the annual average precipitation is 23.25 Inches [3].
During the summer months, the flow in Carneros Creek can drop to zero, causing seawater from the Elkhorn Slough flow into the creek during high tides [4]. Because of this back flow from the slough into Carneros creek, some sources still consider Carneros Creek as part of Elkhorn Slough. The name Carneros Creek, although commonly used in the area, does not always appear in the maps and literature.
Land Cover and Land Use
The area of the Carneros Watershed exhibits mixed land use, including rural residential, grazed grasslands, cultivated areas, and undeveloped areas. Agricultural land use occupies approximately 10% of the watershed of which strawberries are the dominant crop. Other corps include, raspberries, flowers and vegetables [5]. Agro-industrial activities in the watershed include a mushroom growing operation and a chicken ranch [2].
The watershed drains nearly 18,000 acres of steep slopes and flood planes. Carneros soils combined with little development result in almost complete infiltration of water. Run off is caused by bare ground and impermeable surfaces. Agricultural plastics, mulch, and hoop houses accounts for most all impermeable surfaces [5].
Given the current native vegetation of the watershed, it appears that historically the land would have been dominated by native grasslands, oak woodlands, maritime chaparral, and riparian areas. According to Largay [5], the Carneros Creek was then a steady moving stream that moved through numerous wetlands. Activities of settlement, including the reclamation efforts to drain the lower levels of the Carneros Creek, resulted in the loss of these wetlands.
Surface Water and Groundwater Hydrology
There is one main creek that flows through the Carneros Watershed called Carneros Creek. The Carneros Creek is not a perennial creek. According to recent field observations the flow of the Carneros varies according to rainfall and drys up frequently during the summer and occasionally during the winter.
According to the Department of Water Resources, there are at least two groundwater basins within the Carneros Watershed [6], however, as sited in Ferriz [7], the Carneros watershed is occupied by the lower sub-basin of the Salinas Valley Watershed, while according to the Pajaro Valley Water Managment Agency [8], the lower reaches of the Carneros Watershed belong to the Pajaro Valley Groundwater Basin. More research needs to be done on this topic.
Environmental Concerns
As part of the Elkhorn Slough Watershed, the Carneros Creek Watershed is subject to the same potential watershed impacts on Elkhorn Slough. A Management Plan of the Carneros Creek Watershed was prepared by the Carneros Creek Association in 2000 to address areas of concern such as erosion control, sustainable flood management, improvements in water quality, restoration of riparian corridors, and water conservation. The Carneros Creek and its tributaries have not been listed as impaired under the 303-d section of the Clean Water Act.
The Carneros Creek Watershed provides habitat to some species listed as threatened or endangered by the US Fish and Wildlife Service, such as the California Red-Legged Frog (Rana draytonii), California Tiger Salamander (Ambystoma californiense), and the Santa Cruz Long-Toed Salamander (Ambystoma macrodactylum croceum).
Several organizations in the area such as ALBA, the Elkhorn Slough Foundation, ESNERR, and Triple M Ranch provide support, offer educational opportunities, and conduct research in The Carneros Watershed.
Availability of hydrological data
Largay (2007)established rain gages throughout the Carneros creek in order to characterize flows of surface water. Gages are located at Carneros Creek at the Railcar Bridge, at the Sill Road Crossing, at the Johnson Road Bridge, and in the Oxbow Pond. All gages are equipped with temperature recorders, Solinist Leveloggers, and a stilling well. To compensate for barometric changes, Solanist barologgers were installed at all sites. The California State University Monterey Bay has two flow gages in the Carneros Creek, at the Sill Road Crossing, and at the Johnson Road Bridge.
References
- ↑ http://elkhornsloughctp.org/uploads/1238016056Triple%20M%20in%20Context%20Map.pdf
- ↑ 2.0 2.1 Reference text http:://http://sep.csumb.edu/cwsp/theses/Holloway_Thesis_101217.pdf
- ↑ 3.0 3.1 Reference text http://www.idcide.com/weather/ca/aromas.htm
- ↑ Reference text http://www.pvwma.dst.ca.us/hydrology/sw_monitoring.shtml#carneros_creek
- ↑ Cite error: Invalid
<ref>
tag; no text was provided for refs namedLargay
- ↑ Reference text http://www.sierrafoothill.org/watershed/Appendices/Section%203/B%20-%20DWR%20Groundwater%20Basins%20Map.pdf
- ↑ Reference text http://geology.csustan.edu/ferriz/Groundwater_Northern_CA.pdf
- ↑ Reference text http://www.pvwma.dst.ca.us/basin_management_plan/bmp_documents.shtml
Links
- Agriculture and Land-Based Training Association
- Elkhorn Slough Foundation
- Elkhorn Slough National Estuarine Research Reserve (ESNERR)
- Maps of the Carneros Watershed
- Pajaro Valley Groundwater Overdraft Concerns
- Potential watershed impacts on Elkhorn Slough
- Triple M Ranch
- Conditional waiver of waste discharge requirements for irrigated lands