Mayor Julian Castro of San Antonio, Texas, signed a memorandum of understanding on Thursday with the Ein Netafim Eilat water utility to fuel cooperation between the two cities for mutual improvements of their wastewater and recycled-water systems.Over the next two years, the two cities will share expertise and ideas related to operating these systems, with a specific emphasis on desalination, Castro told The Jerusalem Post on Thursday evening. San Antonio is about to construct its first desalination plant, slated to be completed by 2014, and probably financed by the municipality, he explained.Until now, the city has relied entirely on an underground aquifer for its water sources – perhaps the largest US city to do so – and has therefore wanted to diversify its supply sources for the past couple decades, according to Castro.“San Antonio, like Israel, faces the challenge of increasing its water capacity in a very arid climate, and one of the methods that we’re looking at in the next few years is brackish water desalination,” Castro said. He noted that he also visited the Hadera desalination facility on Wednesday.“The folks in Eilat have done both brackish and salt-water desalination, so there’s a number of ways that we can benefit [from the partnership].”While San Antonio will immensely benefit from having a desalination plant, Castro did stress that the city’s residents do a very good job with water conservation.Indeed, water consumption per capita there was 200 gallons per day, and today it has dropped to about 130. Although the number of customers have grown since 1987 by 67 percent, the city uses the same amount of water that it did then, according to Castro.“I will say among the US cities San Antonio is one of the best for water reuse,” he added.In addition to signing the memorandum with Ein Netafim on Thursday, Castro also signed an official cooperation agreement with Tel Aviv Mayor Ron Huldai that day, committing to a joint promotion of economic cooperation and bilateral trade; with a specific emphasis on renewable energy, biotechnology, education and social and cultural affairs, a spokesman for the Castro delegation said.Earlier this week, Castro signed a memorandum of intent on Tuesday with Deputy Mayor of Jerusalem Naomi Tzur, alongside healthcare corporations BioMed SA and BioJerusalem.Meanwhile, he stressed the “warm relationship” between San Antonio’s large Jewish and Hispanic populations during his Jerusalem meetings.But as far as Israel’s water innovations go, Castro told the Post that he was confident San Antonio could learn a lot from the expertise here.“I came away very impressed with the investment that Israel has made in water-resource management and water conservation, as well as the level of innovation and efficiency,” he said.“San Antonio can learn a lot from many of the cities in Israel. They’re doing a good job.”Jeremy Sharon contributed to this report.