washington post article is probably more straightforward, to quote

"The team created a computer model that simulated how a full lake affected the fault. They found high water levels in Lake Cahuilla prompted activity along the fault in two aspects. First, the weight of the lake water caused the crust beneath it to bend, unlocking the plates so they don’t touch as much. The lake water also seeped into the cracks and pores in Earth’s crust beneath it, increasing the fluid pressure inside the fault and further unclasping the plates."

https://www.washingtonpost.com/climate-environment/2023/06/0...

* Sorry for formatting, not really my strength.