Because Karen Bass didn't fill the reservoirs, so all the fire reservoirs were not, so the fire trucks were there, they couldn't pump water.

They cut the water off.

They don't have water.

Surveys show L.A. did have water.

But amid widespread frustration and a report that a local reservoir in the Palisades was offline and empty due to repairs, California Governor Gavin Newsom issued a review of Los Angeles Water and Power.

Here's how the water supply system works and what we know about why hydrants ran out of water at the height of the Palisades fire.

About two-thirds of L.A. County's water comes from sources outside of L.A.

And because L.A. is surrounded by mountains and hills, much of that water has to be pushed up to higher elevations.

Water is heavy, relatively speaking, and so it takes energy to pump it upstream.

Eric Porce, director of the California Institute for Water Resources, says you can think of the system sort of like a tree with interconnected branches.

There are big trunk mains that move water from a source, like a water treatment plant or a reservoir, and carry it to smaller distribution mains, which split off from the trunk.

From there, the water is moved through even smaller pipes or lateral lines that carry water to homes, businesses and fire hydrants.

In some areas, tanks and reservoirs are placed throughout the system to help maintain pressure, because pressure is what pushes water into all of the nodes.

But during the L.A. wildfires, officials said intense demand overwhelmed the system, which drained several tanks and meant that there wasn't enough pressure to push water to hydrants up in the Palisades.

So I want to make sure that you understand there's water in the trunk line that just cannot get off the hill because we cannot fill the tank fast enough.

Officials say there wasn't a lack of water in L.A., and data shows that major California reservoirs were at or above historic averages when the fires broke out.

But in a letter to L.A. officials, Newsom called the ongoing reports of the loss of water pressure to some local hydrants during the fires and the reported unavailability of water supplies from the Santa Ynez Reservoir deeply troubling.

However, a former city official told the L.A. Times that given the severity of the fires, the area still would have experienced serious drops in pressure even with that reservoir.

Those distribution systems aren't really designed to manage wildfire, especially wildfire that was spreading at this rate.

Meanwhile, state officials are pushing back against claims that environmental policies caused L.A. to have water problems, as some blamed Newsom and the state's efforts to protect species like the Delta smelt fish by restricting the flow of some water to Southern California.

You're just letting water run into the Pacific because of what, a fish that no one's heard of?

Does anybody care about the smelt fish?

Incoming President Trump posted he wanted to protect an essentially worthless fish called a smelt by giving it less water.

It didn't work, but didn't care about the people of California.

Now the ultimate price is being paid.

So what's happened is a tragedy and the governor has not done a good job.

What do you say to the criticism that the state has mismanaged water supplies?

I think the facts speak for themselves.

The fact that there is water in reservoirs beyond what is average traditionally for this time of year means that we are moving water when it is available.

And I want to be very, very clear the way that we are moving water and have been moving water and conditions that we're seeing in Southern California around access to that water.

It has nothing to do with protected fish species under the law.

Carla Namath and other California officials say one of the biggest issues was actually wind.

The fire is being fueled by a combination of strong winds and surrounding topography, which is making it extremely challenging for our personnel that are assigned to this incident.

Is there anything California or L.A. officials could have done better to mitigate the threat of these fires?

There will be lots of opportunity after this event to understand what happened.

And we will learn from that and especially in the context of climate.

And we will we will adjust and move forward.

I think it's really important for folks to understand that that a fire suppression strategy for a wildland fire is not dealt with with localized community fire hydrants.

It's just not the right scale.