Geography About Vacaville, California

Vacaville is a city located in Solano County in the northern part of California’s Central Valley. With a population of around 100,000, Vacaville has grown rapidly in recent decades as part of the San Francisco Bay Area metro region. The city’s location along Interstate 80 between San Francisco and Sacramento has fueled economic and population growth. This article will provide an in-depth look at the geography of Vacaville, including its location, topography, climate, and natural features.

Location and Region

Vacaville is situated in central Solano County, approximately 35 miles southwest of Sacramento and 55 miles northeast of San Francisco. The city’s coordinates are 38°21′N 121°58′W.

Vacaville lies within northern California’s Sacramento Valley, which is the northern part of the vast Central Valley that runs through the middle of the state. The Sacramento Valley is bounded by the Sierra Nevada mountains to the east and the Coast Ranges to the west.

As part of the San Francisco Bay Area Combined Statistical Area (CSA), Vacaville is considered to be within the outer ring of the Bay Area metro region. However, it sits just outside the nine-county definition of the Bay Area itself.

Cityscape and Neighborhoods

Vacaville covers a total land area of 28.72 square miles. The city has a number of distinct neighborhoods and districts, including:

• Downtown: Vacaville’s small downtown area features a variety of shops and restaurants along Merchant Street.
• Lagoon Valley: A residential community near Lagoon Valley Park and Lagoon Valley Lake.
• Alamo Drive: A neighborhood south of downtown known for mature trees and mid-century modern homes.
• Vanden: An area in southern Vacaville centered around Travis Air Force Base.
• Allison-Rio Vista: A primarily residential district in eastern Vacaville.
• Elmira: A community in northern Vacaville near Elmira and Gibson Canyons.
• Brown Street: A retail corridor along Brown Street in central Vacaville.

Topography and Geology

Vacaville sits in a relatively flat valley floor, with an average elevation of around 105 feet above sea level. However, there are significant hills and ridges surrounding the city.

To the west rise the low mountains of the Vaca Hills, reaching elevations over 1,500 feet. These hills are part of California’s Coast Ranges. Bedrock in the area includes sedimentary and volcanic rocks.

East of Vacaville, the Potrero Hills and the Sierra Nevada foothills begin to climb up from the valley floor. These low mountains and ridges are composed of metamorphic and igneous rocks.

Within Vacaville itself, the local geology includes alluvial fan deposits washed from the nearby uplands. The downtown area sits atop a large, sloping alluvial fan coming from the Vaca Mountains.

Hydrology and Water Resources

The city of Vacaville gets most of its water supply from surface water sources, including the State Water Project and Solano Project. Water is delivered via the Solano Irrigation District canal system.

Some major bodies of water within or near Vacaville include:

• Lake Berryessa: A large reservoir about 10 miles northeast that provides water and recreation.
• Putah Creek: Flows along the southern edge of Vacaville toward the Sacramento River.
• Alamo Creek: A stream coming down from the Vaca Hills through neighborhoods and Lagoon Valley Park.
• Lagoon Valley Lake: A small lake in Lagoon Valley Park created by damming Alamo Creek.

Groundwater aquifers exist under Vacaville, although overdrafting became a problem in the early 20th century. Today, the city operates 9 different well sites to supplement surface water.

Climate and Weather

Vacaville has a hot-summer Mediterranean climate, characterized by cool, wet winters and hot, dry summers.

Here are some key aspects of the city’s climate:

• Temperatures: Daily highs in summer average around 90°F, with extremes over 105°F. Winter lows average 38°F, with occasional freezing nights.
• Precipitation: Vacaville gets around 22 inches of rain annually, with most rain falling between November and March.
• Snow: Rare in the city itself but possible in the nearby hills. Higher elevation areas get occasional winter snow.
• Fog: Summer morning fog and tule fog occurs due to Vacaville’s proximity to the Sacramento-San Joaquin River Delta.
• Wind: Breezy conditions are common in Vacaville, especially during summer afternoons and evenings.
• Microclimates: The Vaca Hills create slightly cooler temperatures in western parts of the city.

Flora and Fauna

Vacaville’s natural habitats include California prairie grasslands, oak woodlands, riparian zones along creeks and streams, and mixed evergreen forests in the surrounding hills.

Some native plants in the area include wild oats, purple needlegrass, California poppies, oak trees like blue oak and valley oak, buckeyes, willows along stream banks, and chaparral species like manzanita and chamise in the hills.

Wildlife includes black-tailed deer, coyotes, skunks, raccoons, squirrels, opossums, cottontail rabbits, bats, gophers, and many bird species. Reptiles like western fence lizards, gopher snakes, and rattlesnakes can also be found.

Insect diversity is high, including butterflies like monarchs, swallowtail, painted lady, and more. Native bee species are also critical pollinators in the area’s grassland habitats.

Parks and Open Spaces

Vacaville has a diverse collection of public parks, play fields, and open space preserves. Notable ones include:

• Lagoon Valley Park: A 210-acre community park with trails, lakes, gardens, and an observatory.
• Penasco Park: Picnic areas and a playground nestled against the Vaca Hills.
• Al Patch Park: Baseball/softball fields and bocce ball courts near downtown.
• Centennial Park: Vacaville’s largest park with soccer fields, disc golf, and biking trails.
• Vacaville Skate Park: Known for its bowls and street course layout.
• Elmira Horse Arena: Equestrian facility on Oakwood Lane.
• Rockville Trails Ecological Reserve: 200 acres of protected habitat with hiking trails.

Environmental Issues and Conservation

Some key environmental issues and conservation efforts in Vacaville include:

• Air quality: Ozone and particulate matter pollution coming from the Central Valley impacts Vacaville on hot, stagnant days.
• Water: Toxic runoff and pollution threatens creeks. The city promotes low-impact development to protect water quality.
• Tree canopy: Maintaining sufficient shade trees and native oaks through the city’s robust Tree Preservation Ordinance.
• Habitat loss: Balancing growth while preserving remaining pockets of native grasslands and wetlands.
• Sustainability: Expanding clean energy, promoting recycling and composting, creating wildlife corridors, and building LEED-certified municipal facilities.
• Farmland conservation: Careful land use planning to prevent unnecessary conversion of valuable farmland.

Demographics and Population

According to 2019 estimates from the U.S. Census Bureau, Vacaville has:

• A population of 99,755 residents.
• Median age of 36.3 years old.
• Racial/ethnic composition of:
  • 62.9% White
  • 22.4% Hispanic/Latino
  • 7.8% Asian
  • 5.6% Black/African American
  • 0.5% Native American
  • 11.8% Two or more races
• 30.9% have a bachelor’s degree or higher.

Vacaville has grown rapidly since incorporating as a city in 1892, when it had just several hundred residents. Population boomed in the 1970s and 1980s due to housing development and the city’s commutable location between San Francisco and Sacramento.

Transportation Infrastructure

Key transportation infrastructure serving Vacaville includes:

• Interstate 80: Runs along the southern edge of the city, connecting to San Francisco and Sacramento.
• Interstate 505: Provides access to Vacaville from Interstate 5 to the west. Exits lead into the city.
• California State Route 113: Crosses Vacaville in a north-south route.
• Nut Tree Airport: General aviation airport 3 miles southeast of downtown with two runways.
• Amtrak: The California Zephyr route stops at Vacaville’s train station, providing passenger rail service.
• Vacaville City Coach: Operates local bus routes throughout the city.
• Pedestrian/bike paths: A 25-mile network of walking and cycling paths crisscross the city.

Growth and Development Trends

As one of the fastest growing cities in Solano County, Vacaville expects continued population increases in the coming decades. Projects underway include:

• New housing: Both single-family homes and higher-density apartments/condos to meet demand.
• Business parks: Addition of new office and industrial space off I-80.
• Downtown revitalization: New shops, entertainment, and housing to create an active urban core.
• Transit-oriented development: Creating walkable, bikeable neighborhoods around future BART and train stations.
• Infill development: Building on vacant lots within existing developed areas rather than expanding the city’s footprint outward.

Careful planning balances growth with preserving Vacaville’s small-town character and protecting its remaining natural habitats.

Conclusion

From its Central Valley location to its Mediterranean climate, varied topography, and diversity of neighborhoods, Vacaville has a rich geographic identity. Ongoing development and population expansion present environmental and planning challenges for the city, but its abundant parks and open spaces help maintain a connection to nature. The geography of Vacaville will continue shaping the city’s trajectory for decades to come.