San Diego water customers will soon pay $6 to $13 more a month to fund the first part of the city’s new recycled water project, according to a newly released estimate. The city is working on a multibillion-dollar plan to purify enough sewage to provide a third of the city’s drinking water by 2035. Most of Southern California’s water now comes from either the rivers of Northern California or the Colorado River, which are not only hundreds of miles away but prone to drought. The city’s wastewater recycling project, known as Pure Water, is meant to provide more reliable water. Of course, that will come at a cost.