NAPA, Calif. (KGO) --The Napa River stated flooding over the weekend and problems continue to develop. Numerous roads are closed because of rockslides, mudslides and rushing runoff.
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The hillside along Silverado trail is melting in the rain, so the major thoroughfare is closed between Pope Street and Deer Park Road near Saint Helena.
"We determined the roadway was not safe because of the mountain which led to the closure we currently have," said Napa County Public Works Superintendent Dave Cardwell.
When asked if he was worried about more of the mountain coming down Cardwell replied, "Yes, the mountain failed this morning and the geologists have told us it's just a matter of time when the rest of it comes down."
Other roads throughout Napa have moderate flooding that pools up and doesn't drain. Later Tuesday night the Napa River is expected to inundate a bridge at Lodi Lane.
Vineyards are flooding with runoff from the rain. Trees are down and debris is visible floating downstream, but in downtown Napa no flooding is expected thanks to an $18 million bypass completed in 2015.
"For a storm of this magnitude it was a great test and everything worked well," said Napa County Flood Control Manager Rick Thomasser.
The Napa River hit 26.9 feet Sunday night, well over flood stage and no flooding. The bypass starts flowing as waters rise to 23 feet.
More flow to the bypass is expected Tuesday, but it will be half as much as on Sunday.
Officials say the river will crest at 26.1 feet at around 3 a.m. Wednesday morning and isn't expected to cause grat damage.
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