Denniston Creek

Denniston Creek is a 4.4-mile-long (7.1 km)^[1] coastal stream in western San Mateo County, California. Denniston Creek rises on the western slopes of Montara Mountain and discharges to the Pacific Ocean at Pillar Point Harbor somewhat north of El Granada Beach. The watershed of Denniston Creek is made up of relatively permeable sandy soils capable of significant recharge to its aquifers, which supply a moderate amount of potable water to the local area.

Groundwater

In the headwaters reach, high on Montara Mountain, coarse grained decomposed granite overlies heavily fractured granitic based bedrock aquifers.^[2] This upper pocket groundwater complex feeds down-basin alluvial fan deposits on the coastal plain. These alluvial fans exhibit some characteristics of a confined aquifer, but also respond to pressure and recharge from precipitation.^[3]

Mouth

At the mouth of Denniston Creek, the stream cuts through a gently sloping marine terrace plain of alluvium. In a 1980s biological survey, sightings of the endangered San Francisco garter snake were made.^[4] Denniston Creek is within the domain of the San Mateo County Local Coastal Plan^[5]

See also

• Arroyo de en Medio
• List of watercourses in the San Francisco Bay Area
• Rare species
• Riparian zone

37.50383°N 122.486922°W / 37.50383; -122.486922^[6]

References

1. U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map Archived 2012-03-29 at the Wayback Machine, accessed March 15, 2011
2. "Balance Hydrodgeologics Inc.,San Mateo County Mid-Coast Aquifers: Literature Review, prepared for San Mateo county Board of Supervisors (2002)" (PDF). Archived from the original (PDF) on 2007-07-21. Retrieved 2007-02-01.
3. Geoconsultants Inc., Annual report 1988-1989: Groundwater Resources, Half Moon Bay, California, prepared for the city of Half Moon Bay (1989)
4. Earth Metrics Inc., Arroyo de en Medio mouth survey, Miramar, California, prepared for the County of San Mateo (1989)
5. County of San Mateo Local Coastal Plan, San Mateo County Planning Department (1988)
6. U.S. Geological Survey Geographic Names Information System: Denniston Creek