Tassajara Creek

Hacienda Business Park is a 900-acre (364 hectare) mixed-use job center and housing development in Pleasanton, California.

Amador Valley is a valley in eastern Alameda County, California and is the location of the cities of Dublin and Pleasanton. Part of Tri-Valley, the valley is bounded by the foothills of the Diablo Range on the north and south, Pleasanton Ridge to the west, and Livermore Valley to the east. Watercourses draining into the Amador Valley include South San Ramon Creek, Tassajara Creek, Arroyo Mocho, Arroyo Valle, and Arroyo Las Positas, as well as runoff from Pleasanton Ridge. These waters drain south through Arroyo de la Laguna to Alameda Creek, ultimately ending up in San Francisco Bay.

Dublin/Pleasanton station is a Bay Area Rapid Transit (BART) station on the border of Dublin and Pleasanton in California. It is the eastern terminus of the Blue Line. It is also a major bus terminal served by six providers. The station consists of an island platform located in the center median of the elevated Interstate 580. A fare lobby is located under the platform; a pedestrian and vehicle underpass connects the station to bus bays, parking lots, a parking garage, and surrounding development. The Iron Horse Regional Trail connects to both the north and south sides of the station.

The Bernal Subbasin is an aquifer located in the southwestern corner of Livermore Valley Groundwater Basin, Alameda County, California, United States. All of the groundwater in Livermore Valley moves toward the Bernal Subbasin, which is bounded on the east by Pleasanton Fault, on the north by the Park Fault, and on the west by the Calaveras Fault.(Earth Metrics, 1989) All the streams draining the Livermore Valley merge above the Bernal formation and exit this subbasin and Livermore Amador Valley via the Arroyo de la Laguna. Groundwater occurs throughout the valley floor portion of the Bernal Subbasin under conditions ranging from unconfined to confined. There is no inflow of groundwater across the Pleasanton Fault south of the City of Pleasanton, because any movement of groundwater in the southern section is essentially parallel to the fault.(Bonnie, 2000) Groundwater in the Bernal Subbasin typically occurs at an approximate depths of 12 to 30 feet (3.7 to 9.1 meters) below ground surface and flows from east to west.

Tulare Lake was a large, shallow lake in eastern Amador Valley, surrounded by Willow Marsh (also known as the Lagoon). Tule rushes and willow trees once lined the marshes and sloughs of its shores. Drainage alterations starting in the 19th century have since reduced the marsh to the Arroyo de la Laguna, and the city of Pleasanton has since expanded across what was once marshland. Such rapid developments have led to tricky seasonal flow variations in Niles Canyon.The lake was fed by Arroyos Mocho, Valle, and Las Positas (when rainfall was substantial enough for them to reach the lagoon), as well as by Tassajara Creek and other Amador Valley creeks. Its seasonal outlet was the Arroyo de la Laguna. Tulare Lake was densely inhabited by groups of the Ohlone people prior to the 19th century.

Amador Valley High School is a comprehensive public high school in Pleasanton, California. It is one of three high schools in the Pleasanton Unified School District, along with Foothill High School and Village High School. Founded as Amador Valley Joint Union High School (AVJUHS), it graduated its first class in 1923. Major construction and renovations were undertaken after district voters approved bonds in 1922, 1965, 1997, and 2016. The school is a four-time California Distinguished School and a three-time National Blue Ribbon School. In national competitions such as We the People: The Citizen and the Constitution, the Amador Valley team has won the 1995 and 2022 national titles. The Amador Valley Wind Ensembles have performed at national venues and conferences, including Carnegie Hall and the Midwest Clinic. Several Amador Valley athletic teams have won multiple California Interscholastic Federation North Coast Section Division I titles since 2010, including the softball team which MaxPreps named 2014 mythical national champion following a perfect season.

Ozark High School is a high school in Ozark, Missouri. Ozark High School is an International Baccalaureate World School.

South San Ramon Creek is a 9.3-mile-long (15.0 km) southward-flowing stream in Alameda County and southern Contra Costa County, in the East Bay region of northern California. The creek is a tributary to Arroyo de la Laguna, flowing in the western Livermore Valley through Dublin and Pleasanton.

Arroyo Mocho is a 34.7-mile-long (55.8 km) stream which originates in the far northeastern corner of Santa Clara County and flows northwesterly into eastern Alameda County, California. After traversing the cities of Livermore and Pleasanton it joins South San Ramon Creek to become Arroyo de la Laguna, which in turn flows to Alameda Creek and thence to San Francisco Bay.

The Alameda County Fairgrounds is a 270-acre (110 ha) facility located in Pleasanton, California. It is home to the annual Alameda County Fair, held since 1912, as well as numerous trade shows and community events. Located on its grounds, the Pleasanton Fairgrounds Racetrack was built in 1858, making it the oldest one-mile (1.6 km) horse racing track in the United States. There is a 3,000 seat amphitheater, as well as a 9-hole golf course located within the track's infield. The Alameda County Central Railroad Society has maintained a model train exhibit at the fairgrounds since 1959, which has grown to two 15-by-100-foot (4.6 by 30.5 m) layouts in O scale and HO scale.Building J, also known as the Amador Pavilion, is a multi-purpose arena and livestock event facility at the fairgrounds. It was briefly home to the Tri-Valley Ranchers of the National Indoor Football League. Fair cancellations happened in 1917–1918, 1942–1944 and 2020.

Rancho Santa Rita was a 8,894-acre (35.99 km2) Mexican land grant in the Amador Valley and western Livermore Valley, which is in present day Alameda County, California. It was given in 1839 by Governor Juan Alvarado to Jose Dolores Pacheco.The rancho included present day Pleasanton, Asco, and Dougherty.

The Tri-Valley area is grouping of three valleys in the East Bay region of California's Bay Area. The three valleys are Amador Valley, San Ramon Valley, and Livermore Valley. The Tri-Valley encompasses the cities of Dublin, Livermore, Pleasanton and San Ramon, the town of Danville and the CDPs of Alamo, Blackhawk and Diablo. The area is known for its Mediterranean climate, wineries, and nature. It is primarily suburban in character. The United States Census Bureau defines an urban area centered in the cities of Livermore, Pleasanton, and Dublin with a 2020 population of 240,381, ranked 167th in the United States in terms of population. The total population of the area is estimated to be 361,000. It offers more affordable living accommodations than the cities of San Francisco and San Jose.