The aqueduct's construction was controversial from the start, as water diversions to Los Angeles eliminated the Owens Valley as a viable farming community.

[9][11] The continued operation of the Los Angeles Aqueduct has led to public debate, legislation, and court battles over its environmental impacts on Mono Lake and other ecosystems.

To move 14 million ton-miles of freight, the city contracted with Southern Pacific to build a 118 mile long rail system from the Monolith mills to Olancha.

[23] A group labeled the "San Fernando Syndicate" – including Fred Eaton, Mulholland, Harrison Otis (the publisher of The Los Angeles Times), Henry Huntington (an executive of the Pacific Electric Railway), and other wealthy individuals – were a group of investors who bought land in the San Fernando Valley allegedly based on inside knowledge that the Los Angeles aqueduct would soon irrigate it and encourage development.

[23] Although there is disagreement over the actions of the "syndicate" as to whether they were a "diabolical" cabal or only a group that united the Los Angeles business community behind supporting the aqueduct,[24][25] Eaton, Mulholland and others connected with the project have long been accused of using deceptive tactics and underhanded methods to obtain water rights and block the Bureau of Reclamation from building water infrastructure for the residents in Owens Valley, and creating a false sense of urgency around the completion of the aqueduct for Los Angeles residents.

The lake has never been refilled, and is now maintained with a minimum level of surface water to prevent the introduction of dangerous, toxic lake-floor dust into the local community.

On March 12, 1928, the dam catastrophically failed, sending a 100-foot high (30 m) wall of water down the canyon, ultimately reaching the Pacific Ocean near Ventura and Oxnard, and killing at least 431 people.

The resulting investigation and trial led to the retirement of William Mulholland as the head of the Los Angeles Bureau of Water Works and Supply in 1929.

The dam failure is the worst man-made flood disaster in the US in the 20th century and the second largest single-event loss of life in California history after the 1906 San Francisco earthquake.

The construction of the Mono extension consisted of an intake at Lee Vining Creek, the Lee Vining conduit to the Grant Reservoir on Rush Creek, which would have a capacity of 48,000 acre⋅ft (59,000,000 m3), the 12.7 mi (20.4 km) Mono Craters Tunnel to the Owens River, and a second reservoir, later named Crowley Lake with a capacity of 183,465 acre⋅ft (226,301,000 m3) in Long Valley at the head of the Owens River Gorge.

[12] The results of the litigation culminated with a SWRCB decision to restore fishery protection (stream) flows to specified minimums, and raise Mono Lake to 6,391 feet (1,948 m) above sea level.

Faced with the possible loss of future water supply, Los Angeles began the five-year construction of the aqueduct in 1965 at a cost US$89 million.

The Los Angeles Department of Water and Power managed the project and performed some finishing construction on the Mojave conduit and Jawbone & Dove Spring pipelines.

The flow then continues 115 miles (185 km) south through a series of pressure pipelines and concrete conduits where it connects with the First Aqueduct at the North Portal of the Elizabeth Tunnel near the Fairmont Reservoir.

Water from the Terminal structure can then flow to either the Cascade or penstock to the Foothill Power Plant and into the Upper Van Norman Reservoir.

William Mulholland continued adding capacity to the aqueduct, building the St. Francis Dam that would impound water creating the San Francisquito Reservoir, filed for additional water from the Colorado River, and began sending engineers and miners to clear the heading at the San Jacinto Tunnel that he knew was key to the construction of the Colorado River Aqueduct.

[49] According to archaeologists and anthropologists, the Paiute people, also known as Nüńwa Paya Hūp Ca’á Otūǔ’m (translates to “We are Water Ditch Coyote children"), settled in the Owens Valley region as early as 600 C.E., having long adopted and specialized in a hunting and harvesting economy.

[54] The impact of the Los Angeles Aqueduct Project to the Owens Valley region was immediate and detrimental to future agricultural work of local farmers.

[60] In 1991, the City of Los Angeles signed the Inyo-LA Long Term Water Agreement despite objections from community members and stakeholders.

[64] Los Angeles faces significant challenges in securing its water supply for the future due to climate change, population growth, and increasing competition for resources.

[66] Efforts to address these challenges include transitioning to more sustainable, local sources such as reclaimed water, desalination, and rainwater harvesting.

[65] Water scarcity is a growing concern in Los Angeles, driven by factors such as climate change, population growth, and environmental obligations.

[65] Reduced Sierra Nevada snowpack and changing precipitation patterns have jeopardized the reliability of the Los Angeles Aqueduct, while prolonged droughts strain access to water from the Colorado River and other sources.

Legal requirements mandate water retention in Owens Valley and Mono Lake to address ecological damage caused by aqueduct operations.

[66] Despite these challenges, urban water conservation measures, including rainwater harvesting and improved irrigation practices, offer promising strategies for mitigating scarcity.