Diverting streams to go into different places increases the dwell time of the water by 45 days. when you have a rigid dry season, keeping the streams running for an extra 45 days is absolutely fucking huge. The clever part is that over the years the locals have managed to find the best place to divert water so it goes into springs that feed streams.
its a similar idea to a Johad, https://en.wikipedia.org/wiki/Johad which traps water for a number of days, increasing the dwell time and making the place wetter. The issue with Johads is that they can be a magnet for mosquitos. Johads differ in that they force the water into the soil rather than aquifers.
In LA, everything is done to make sure the water yeets into the sea as quick as possible. That water that would have hung around is replaced with the water from the LA aqueduct and the like. THe place gets drier, and hotter. I would wager, but can't assert that this water mismanagement is causing a large part of the drought in that area.
> In LA, everything is done to make sure the water yeets into the sea as quick as possible.
The infrastructure bill may change that [0]:
"Also, the money could fund stormwater capture and reuse projects, like the ones that filter rainwater into underground aquifers rather than let it flow into the ocean."
Unlikely since it rains so few times the cost to benefit ratio is terrible. Instead the city has been treating wastewater and using that constant source of greywater to irrigate public parks and recharge aquifers.
The biggest issue with the west was that it was in a historic wet period 100 years ago when water rights laws were solidified with different groundwater levels. Its a drought only relative to this time, historically in Southern california it is usually dry like this. The issue with runoff water in LA and other cities is that its super polluted. You don’t even want to swim in the ocean after a rain. If you wanted to be smart about it you would have to treat it, but it rains in earnest so few times that building that infrastructure would be too costly if its only going to be used when it deluges 6 times a year.
What the city has been doing instead is honestly a better long term move imo. They treat sewage and turn it into grey water, which is used to water public grass spaces like parks and is starting to be used as well as recharge local aquifers since the state says the ground is the best filter for grey water.
Diverting streams to go into different places increases the dwell time of the water by 45 days. when you have a rigid dry season, keeping the streams running for an extra 45 days is absolutely fucking huge. The clever part is that over the years the locals have managed to find the best place to divert water so it goes into springs that feed streams.
its a similar idea to a Johad, https://en.wikipedia.org/wiki/Johad which traps water for a number of days, increasing the dwell time and making the place wetter. The issue with Johads is that they can be a magnet for mosquitos. Johads differ in that they force the water into the soil rather than aquifers.
In LA, everything is done to make sure the water yeets into the sea as quick as possible. That water that would have hung around is replaced with the water from the LA aqueduct and the like. THe place gets drier, and hotter. I would wager, but can't assert that this water mismanagement is causing a large part of the drought in that area.