My main plot delves into the history of the Hohokom Indians that live here in Arizona before Phoenix was founded. They were several thousands large and had, for the time, advances systems of irrigation and what not. But by the time the eventual founders of Phoenix got here there were nothing but ruins of the civilization. History has it they suffered a bad drought.
BUT, in the dresdenverse they fell victims of the summer court. They performed a massive ritual that created a giant flash fire across a huge portion of the state. With he intent that from the ashes l, new, more, and better life will flourish. And now in the present time, summer is starting to make preparations to do it again.