 Despite its look, the rope bridge was actually quite elaborate in  its construction and contained numerous safety devices as well as  hydraulic lifts in order for the special effects crew to manipulate  it into motion. It cost one million dollars to build. After it was  completed, the original river for the scene (in the Dominican  Republic) went almost completely dry for the first time in its  history due to a drought. The bridge had to be torn down and a new  location in Tuxtepec Mexico was found. The bridge had to be rebuilt  at the cost of another one million dollars. However once again at  the new location the raging river started to dry. The crew had to  put a 24 hour guard around the bridge because the superstitious  locals threatened to blow it up believing it was the  bridge/intruders that caused the river to become shallow. By the  time filming began the water was only 18 inches deep and looked  completely nonthreatening. The crew didnt have the time or the  money to find yet another location so Friedkin decided to add an  artificial current and rainstorm (using helicopters/wind machines  and men on towers with giant hoses.) The bridge itself was so  rickety that despite the safety precautions the truck (often with an  actor inside of it) slid off the side and into the shallow water  five times during rehearsals and filming. The entire sequence took  three months to shoot. Friedkin stated it was by far the most  difficult sequence he ever filmed in his career.