Texas Governor Greg Abbott pledged on Wednesday to overhaul the state's electric grid operator after a massive blackout left residents without heat, power or water for days.

All of the five board directors who are stepping down live outside of Texas, which only intensified criticism of the Electric Reliability Council of Texas.

Millions of Texans were advised to boil water before using it, though all power plants were back online over the weekend and power had been restored to most homes.