For those of you who have never seen it, the Tridge is a "three-span pedestrian bridge" providing passage to three land areas on Midland's downtown riverfront. The walkways are eight feet, three inches wide, and the triangular observation area in the center measures 35 feet per side. The wooden decking and beams filled six train cars. Although the majority of the Tridge is wood, there are 20 tons of steel in the structure in the form of bolts and connectors. A cofferdam - an enclosed circular cell formed from steel sheet piling - was driven into the river bed and then pumped dry to keep water out while the central concrete pier was built. A causeway - essentially a road in the middle of the river - was built from concrete rubble to allow a crane to approach the center construction area.