This utilitarian, medium-scale viaduct was designed in accordance with traditional rather than 1810 state-of-the-art practice. It did not incorporate the hollow cross-tied spandrel improvement then being adopted with increasing frequency by leading engineers. If this had been adopted here instead of clay fill, it would have obviated the spandrel bulging and some of the stone loss that occurred. Much of the viaduct's stone quality and some workmanship at the west end were only just adequate for the purpose ... but the flat-stone, lime-mortar-bedded, pier hearting carried up to 1.5 m above arch springing was an effective feature which had probably saved the piers from collapse. In cross-section, the spandrels presented an unusual application of the classic gravity retaining wall.