By Nick Cahill, Courthouse News

(CN) – A federal agency contributed $84 million to a $16 billion water project in California under the nose of Congress and taxpayers, according to a federal audit released Friday.

The audit says for several years the U.S. Bureau of Reclamation picked up the tab for California water districts and gave federal taxpayer dollars to a contentious plan to divert fresh water around the West Coast’s largest estuary through a pair of 35-mile tunnels.

According to the audit by the U.S. Interior Department’s inspector general, the Bureau of Reclamation under President Barack Obama shifted millions in general purpose funds toward a plan to restore the Sacramento-San Joaquin River Delta and essentially subsidized planning costs that were supposed to be paid by local water suppliers.

“The bureau obtained this $50 million over a seven-year span by using a complex, obscure process that was not disclosed in the annual congressional budget justifications,” the audit states.

In 2014, Gov. Jerry Brown shifted focus of the restoration project to his plan to dig twin tunnels through the delta, called California WaterFix. While that project’s mammoth $16 billion estimated price tag is supposed to be funded by California and water contractors, the federal government has contributed 33 percent of the funding through 2016, according to the audit.

Auditors blasted the bureau for classifying the $50 million as nonreimbursable, meaning the funds won’t be repaid by the water districts benefitting from the project.

“The bureau was unable to provide documentation or analysis supporting its determination that these funds were nonreimbursable, and we question the bureau’s interpretation of this legal authority,” the audit states.