Thread by @nithyavraman

It's gonna rain this week! Believe it or not, an average storm in LA brings about ten billion gallons of water.

Rainwater is vital to our water-insecure city. So how much do we end up capturing?

*Only about 30%.* The rest runs into the ocean.

But we can change that. (thread)

First, let's talk about where LA's water comes from. The answer: mostly not LA.

About 85% of our water comes from outside sources, primarily Northern California and the Colorado River.

So we're dependent on water that travels a long way. That's a problem because...

Importing water costs LA a billion dollars a year. As water gets more scarce, that price is likely to go up.

Long aqueducts are also vulnerable to earthquakes.

A big one could damage the infrastructure that carries our water, and the city could dry up in a matter of days.

We've also recently had some major dry years in LA. Rains in 2017 pulled us out of drought, but we're still in "Abnormally Dry" conditions.

And as the climate changes, droughts are going to get more common.

That's why LA needs to become water independent.

A water-independent LA sounds crazy, I know. But it's possible! We get more gallons of rain in an average year than the city needs.

UCLA put out a study laying out a roadmap to water independence. The headlines were:
- Cut usage
- Capture more stormwater
newsroom.ucla.edu/releases/ucla-…

A big part of capturing stormwater is just letting it pass through the soil into our underground aquifers.

LA sits on a *huge* aquifer that's only at about 60% of capacity, even after recent rainy years. Replacing cement with more permeable surfaces would help fill it up!

How have we done on cutting usage? Unfortunately, not great.

We used a lot less during the drought years, but after the rains, the city stopped enforcing conservation and our usage went right back up to pre-drought levels.

Our stormwater capture progress is also discouraging.

In 2015, LADWP put out a Stormwater Capture Master Plan. It's great! But like a lot of city plans, it's barely been implemented.

The goal was to outfit 4.5% of LA homes with stormwater capture equipment each year.

Four years later, they've done about 1/10th of one percent.

The reasons we're so water-insecure in LA are not complicated.

1) The city surface is mostly cement. Rainwater can't penetrate cement and gets run off into the ocean.

2) Most of our surface that isn't cement is lawn. Lawns are thirsty. We use *half* of our water on landscaping.

But all of these problems are solvable.

With a city-wide mobilization, encouraging and subsidizing beautiful drought-tolerant gardens and permeable surfaces, we can achieve water independence here.

Given where our climate is headed, we need to.

You can read more about water policy and LA's climate future in my Energy and Enviromment platform here! nithyaforthecity.com/platform/envir…