The Ohlone Indians were the original inhabitants of the canyon that now holds Loch Lomond Reservoir. Of the Ohlone, the local group was referred to as the Zayante. They had enough acorns, fish and small game to live a peaceful, easy life. The Spanish and mission life brought an end to the Ohlones in the 1800s.
The land was then owned by a succession of wealthy families, among them was Addison Newell, the man after whom the creek feeding Loch Lomond was named. Like most of the San Lorenzo Valley, the land around Newell Creek was logged heavily in the late 1800s and early 1900s. The forest is in the process of re-establishing itself on the young, steep slopes of marine sedimentary rock common to the California coast. The city of Santa Cruz purchased the land and developed the reservoir in the late 1950s. The recreation Area opened in 1963