Bulletin 1.pdf - California Department of Water Resources - State of ...

CHAPTER VI. CENTRAL COASTAL AREA
Both geographically and climatically, the Central Coastal Area is a
transition zone between the North Coastal and San Francisco Bay Areas
and the South Coastal Area.
LOCATION AND DESCRIPTION
This Area lies along the Pacific Ocean, between latitudes 34!0 and
37° N., from the southern boundary of Pescadero Creek Basin, in Santa
Cruz County, to the southeastern boundary of Rincon Creek Basin, in
Ventura County. Inland it extends an average of about 50 miles to the
crests of the coastal ranges.
Summer fogs are common along the coastal strip. In interior valleys
there is a marked contrast between summer and winter temperatures,
with summer highs reaching 110° F. and winter lows occasionally falling
to 16° F. Near the coast the Santa Cruz, Santa Lucia, and Santa Ynez
Mountains are the main topographic features, with elevations of 3,801
feet at Lorna Prieta in the Santa Cruz Mountains, 5,844 feet at Junipero
Serra Peak in the Santa Lucia Range, and 6,828 feet at Big Pine Mountain
in the San Rafael Range. Elevations in the Diablo Range, on the
western side of basins draining interior portions of the Area, are 5,248
feet on San Benito Mountain at the head of San Benito River, and 8,750
feet on Sawmill Mountain at the head of Santa Maria River.
STREAMS AND AREAS OF DRAINAGE BASINS
Principal streams of the Central Coastal Area are Pajaro, Salinas,
Santa Maria, and Santa Ynez Rivers, which drain the larger basins to
the crests of the Gabilan, Diablo, San Rafael and Santa Ynez Mountains,
and San Lorenzo, Carmel, and Big Sur Rivers, and Scott, Morro, San
Luis Obispo, Arroyo Grande, San Antonio, and Rincon Creeks, which flow
directly into the Pacific Ocean along the coastal slope. Two-fifths of the
Area lies within the basin of Salinas River and its tributaries. This basin,
about 170 miles long, approximately parallels the coast, from which it is
separated by the Santa Lucia Range. Areas ofdrainage basins in the Central
Coastal Area are listed in Table 31.
PRECIPITATION
Precipitation on the Central Coastal Area is moderate except in a
few isolated sections, and decreases from north to south. Snow normally
falls in limited amounts at higher altitudes but is rare on the valley
floors. The definite influence exerted by mountain ranges on precipitation
is indicated by greater density of vegetation on their western slopes.
Mountains may also affect distribution of precipitation in the interior
valleys. For instance, precipitation from major storms crossing Salinas
Valley is substantially heavier on the west side of the valley than on
the east side.
( 135 )