California cities and towns may find themselves on a water budget in the next decade under a pair of bills approved Thursday by the legislature. The measures follow Gov. Jerry Brown’s call to make water conservation a permanent way of life in a state long accustomed to jewel-green lawns and suburban tracts studded with swimming pools. More than a year of legislative negotiations reflected the enduring conflicts over state and local control. Though the bills establish a framework to end excessive urban water use, the proposals were substantially weakened by a series of amendments sought by water districts.