A nonconductive bridge element is secured to a pair of end plates in a conduit retainer apparatus in a trench. The pair of end plates are secured to a trench wall by dowels extending through holes in the end plates and the bridge element is disposed in the trench on top of conduits. The end plates are two piece elements, a plate and an insert pin extending through the plate. The center bridge element comprises a nonconductive tube, the ends of which receive the insert pins.