Texas water planners stand ready to approve a $53 billion road map for satisfying the state’s thirst over the next half-century but have not resolved how to pay for it.

The perils of not paying for the state’s plan, intended to prevent grave water shortages by 2060, already are evident in the price tag. The cost has risen from $31 billion in 2007, the last time the Texas Water Development Board updated the plan. The 2002 version was estimated at $18 billion.