Among the last cities downstream to receive water from the shrinking Colorado River, Tijuana is staring down a water crisis driven also by aging, inefficient infrastructure and successive governments that have done little to prepare the city for diminishing water in the region.Entire neighborhoods on Tijuana's hilly and sometimes grassy far reaches remain unconnected to the city’s water mains and pipes.Accessing water there is a daily struggle — and an expensive one as trucked-in water usually costs much more than what those connected to the city pay.