After a five-hour packed public hearing, the board of Silicon Valley’s largest water provider late Wednesday night put off a closely watched vote until next week on whether to provide up to $650 million to support Gov. Jerry Brown’s $17 billion plan to build two giant tunnels under the Sacramento-San Joaquin River Delta to make it easier to move water south. Although it appeared there might be four votes on the seven-member Santa Clara Valley Water District board in favor of the project, which the Brown administration calls WaterFix, board members were divided and continued the issue until Tuesday at 9:30 a.m.