US efforts to help rebuild Haiti after the devastating 2010 earthquake have been plagued by poor planning, delays and mistaken cost estimates that have forced many projects to be scaled back, the US' Government Accountability Office (GAO) has concluded in a recently-released report. Of the $US651 million ($A708.22 million) Congress allocated for Haiti reconstruction to the US Agency for International Development, only $US204 million has been spent three years later. And much of that has gone to questionable use, the GAO found. The GAO was especially critical of USAID's largest reconstruction project, a $US170.3 million undertaking that includes construction of a power plant, a port and an industrial park.