The Vauxhall Bridge Company ran into financial difficulties and was unable to raise more than the £300,000 stipulated in the 1809 Act, and a new Act was passed in 1812 permitting the Company to build a cheaper iron bridge. Rennie submitted a new design for an iron bridge of eleven spans, costing far less than the original stone design. Rennie's design was rejected, and instead construction began on a nine arch iron bridge designed by Samuel Bentham. Concerns were raised about the construction of the piers, and engineer James Walker was appointed to inspect the work. Walker's report led to the design being abandoned for the second time, and Walker himself was appointed to design and build a bridge of nine cast-iron arches with stone piers, the first iron bridge to be built across the Thames.