Two double concrete box culverts along an inner city stream were causing backup of stormwater. An upstream structure did so by catching debris on the middle wall. The downstream structure was also a low water crossing with a sewerline passing through the middle of the box. One structure was located on an arterial street so replacement had to be done while school was out of session.
These structures were replaced with precast arch type structures using precast foundations to speed construction. The sewerline was replaced in an alternate location and both structures were replaced within a 3 month period.