Lake Oroville is 99% full with more snow to melt. Why water managers say the reservoir won't overflow

This is the most water that Lake Oroville has had at this point in the year since 2012, according to the Department of Water Resources

This is the most water that Lake Oroville has had at this point in the year since 2012, according to the Department of Water Resources

TECHNICAL WITH LESS HARM TO THE PUBLIC. WELL, IT’S EARLY JUNE AND MANY OF NORTHERN CALIFORNIA’S RESERVOIRS ARE JUST ABOUT FULL, AND THERE IS STILL PLENTY OF SNOW IN THE SIERRA. NOW, SOME OF YOU ARE ASKING WHETHER THAT’S A PROBLEM FOR LAKE OROVILLE. METEOROLOGIST HEATHER WALDMAN GETS SOME ANSWERS FOR US. LAKE OROVILLE HASN’T HAD THIS MUCH WATER AT THIS POINT IN THE YEAR SINCE 2012. AS OF MIDDAY TUESDAY, THE LAKE IS AT 99% OF CAPACITY AND IT’S STILL FILLING UP WITH MORE WATER FLOWING IN THAN WHAT’S BEING RELEASED. WE’VE GOTTEN SEVERAL QUESTIONS FROM YOU ASKING ABOUT THE WATER LEVEL PLANNED RELEASES AND WHETHER OR NOT ORRVILLE IS ACTUALLY GOING TO OVERFLOW. NOW, FOR STARTERS, YES, THE WATER LEVEL IS JUST A COUPLE FEET BELOW WHAT WOULD BE CONSIDERED FULL. BUT FOR SOME PERSPECTIVE, REMEMBER THE SHAPE OF LAKE OROVILLE. IT’S A REALLY DEEP V, AND YOU CAN KIND OF GET A SENSE FROM THAT, FROM THIS VIDEO BACK IN NOVEMBER OF 2021, WHEN THE LAKE LOOKED HALF EMPTY, THE LAKE BED MAKING THAT DEEP V SHAPE. SO BY VOLUME, THERE’S A LOT MORE WATER THAT CAN BE HELD IN THE TOP TWO FEET OF THE LAKE VERSUS LOWER DOWN IN THE LAKE. I ALSO DID A LITTLE BIT OF MATH. LAKE OROVILLE STILL HAS 30,000 ACRE FEET OF STORAGE LEFT. IF THE AMOUNT OF RUNOFF WERE TO STAY THE SAME FOR THE NEXT COUPLE OF WEEKS, IT WOULD STILL TAKE ABOUT THREE WEEKS FOR THE LAKE TO TOTALLY FILL UP. BUT THE DEPARTMENT OF WATER RESOURCE SAYS THAT THE INCOMING WATER HAS BEEN SLOWING DOWN FOR A WHILE. OUR PEAK INFLOW OCCURRED BACK IN APRIL OF THIS YEAR. AND SO WHAT WE’VE DONE IS WE’VE SEEN THE INFLOW HAS BASICALLY DECREASED SINCE THAT TIME. AND SO AS WE’RE GETTING INTO THE SUMMER, WE’LL SEE PERIODS OF TIME WHERE THE RESERVOIR, THE INFLOW WILL COME UP A BIT, BUT THE OVERALL TREND IS DOWNWARD. AND THAT INFLOW, OF COURSE, COMES FROM SNOWMELT. AND ACCORDING TO THE CENTRAL SIERRA SNOW LAB, THERE’S STILL 14.5IN OF WATER AT THAT SITE. YARBOROUGH ADDED THAT WE ARE NOW AT THE POINT IN THE YEAR WHEN RELEASES ACTUALLY NEED TO BE INCREASED FROM OROVILLE, NOT FOR FLOOD CONTROL, BUT BECAUSE THE DEMAND FOR DRINKING WATER STARTS GOING UP. AT THIS POINT, LAKE OROVILLE IS THE LARGEST RESERVOIR IN THE STATE WATER PROJECT, WHICH PROV

Lake Oroville is 99% full with more snow to melt. Why water managers say the reservoir won't overflow

This is the most water that Lake Oroville has had at this point in the year since 2012, according to the Department of Water Resources

As of Tuesday, Lake Oroville is at 99% of capacity, with more than 3.5 million acre-feet of water being stored. According to the Department of Water Resources, Lake Oroville has not been this full at this point in the year since 2012. As more snow melts from the Sierra, more water is flowing into the lake than what is being released, meaning that the water level is continuing to slowly creep up. Water managers with the Department of Water Resources say that despite that continuing snowmelt, there is no reason to worry about Lake Oroville overflowing. “Our peak inflow occurred back in April of this year. And we’ve seen basically the inflow has decreased since that time," says John Yarbrough, who is the assistant deputy director for the State Water Project. Even if inflows were to remain steady, water managers say they would have plenty of time to adjust releases to keep the lake within its bounds. But Yarbrough says that inflows will decrease overall through June. “So with that decreasing inflow, we’re able to watch that and see any changes that will be coming on the horizon and then adjust our outflows accordingly," Yarbrough said.In the case of a major heat wave or a rare late-season storm, Yarbrough said there would be plenty of time for releases to be temporarily increased to keep up with increased inflows, maintaining a safe water level. During the summer months, increased releases are made from Lake Oroville as demand for that stored water increases. Lake Oroville is the largest reservoir in the State Water Project, which provides drinking water to 27 million Californians. Releases for water deliveries draw Lake Oroville's level down through the fall.DWR announced in April that because Lake Oroville and other major reservoirs are full, the State Water Project would be delivering on 100% of water requests this year. That has not happened since 2006. | Video Below | Meteorologist Heather Waldman joins LiveCopter 3 over Lake Oroville, Feather Falls

As of Tuesday, Lake Oroville is at 99% of capacity, with more than 3.5 million acre-feet of water being stored.

According to the Department of Water Resources, Lake Oroville has not been this full at this point in the year since 2012.

As more snow melts from the Sierra, more water is flowing into the lake than what is being released, meaning that the water level is continuing to slowly creep up.

Water managers with the Department of Water Resources say that despite that continuing snowmelt, there is no reason to worry about Lake Oroville overflowing.

“Our peak inflow occurred back in April of this year. And we’ve seen basically the inflow has decreased since that time," says John Yarbrough, who is the assistant deputy director for the State Water Project.

Even if inflows were to remain steady, water managers say they would have plenty of time to adjust releases to keep the lake within its bounds. But Yarbrough says that inflows will decrease overall through June.

“So with that decreasing inflow, we’re able to watch that and see any changes that will be coming on the horizon and then adjust our outflows accordingly," Yarbrough said.

In the case of a major heat wave or a rare late-season storm, Yarbrough said there would be plenty of time for releases to be temporarily increased to keep up with increased inflows, maintaining a safe water level.

During the summer months, increased releases are made from Lake Oroville as demand for that stored water increases. Lake Oroville is the largest reservoir in the State Water Project, which provides drinking water to 27 million Californians. Releases for water deliveries draw Lake Oroville's level down through the fall.

DWR announced in April that because Lake Oroville and other major reservoirs are full, the State Water Project would be delivering on 100% of water requests this year. That has not happened since 2006.

| Video Below | Meteorologist Heather Waldman joins LiveCopter 3 over Lake Oroville, Feather Falls

Lake Oroville is 99% full with more snow to melt. Why water managers say the reservoir won't overflow

This is the most water that Lake Oroville has had at this point in the year since 2012, according to the Department of Water Resources

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