The San Diego City Council voted unanimously Tuesday to certify an environmental impact report for the city’s nearly $3 billion plan to recycle wastewater into drinking water, and approved the plan itself. Supporters of the so-called “Pure Water San Diego” program say it will provide residents and businesses with a stable, local supply of potable water that won’t be affected by drought or the uncertainties of future water imports. The product will be purified and mixed with water from traditional sources before it’s delivered to customers.