NO NEW TALES HAVE BEEN RECEIVED. NEW TALES WILL BE POSTED WHEN RECEIVED.
The topographic survey indicated that a manhole lid was labeled "GAS". The survey noted that the structure was filled with debris and "smelled". The utility atlas indicated an abandoned gas line in the vicinity. A water line was to be constructed adjacent to the manhole. The "smelly" manhole turned out to be part of a sanitary sewer system that was still in operation. The plans were prepared to remove the abandoned gas line, since the gas company responded that they did not have any facilities in the area. When the manhole was excavated with a single tug from a large backhoe, a lot of faces showed surprised looks and a lot of people were affected. Topo once, Check twice.
A construction layout provided a single stake at a radius return. The stake was labeled "3FT O/S". The plans called for a catch basin and curb at the radius. The center of the drainage structure was placed from the stake, so the sewer was laid through the drainage structure. The curb crew used the stake for the back of curb, so the curb ran across the top of the structure. The pavers came and went. After inspection, the curb was re-laid to expose the opening to the structure, leaving a major turnout at the radius return that was not intended. The intersecting street matched the curb at the end of the radius, making it about two feet off-center with the rest of the block. The street stands today as a reminder to communicate before you excavate.
A vehicle detector loop was to be placed on an intersecting side street following the installation of a signalized intersection. No work had been done on the side street. The plans contained a note, a pay item for sawcutting the loop and the lead-in wire, and a standardized detail for the placement of the loop in the pavement. The project had been delayed by snow, and the signals were to be inspected the following week. The construction superintendent and the resident engineer were not on site. The sub-contractor arrived to perform the saw-cut. A lite snow began to fall. The saw-cut depth was 3/4-inch. The office engineer was new to the project, but handed the sub-contractor a copy of the detail, paced off the distance to the loop and went back into the trailer. The sub-contractor sawed the lead-in line - through the snow-covered pavement - across a bridge expansion joint, bridge deck a second expansion joint and a reinforced approach slab.
The "boiler plate" signal plans called for buried conduit to be run from a loop detector to the controller, a distance of approximately 450 feet. The quantities did not cover the driveway replacement, pedestrian cross-walk or the box culvert that had to be crossed between the detector and the controller. To add insult to injury, a "Buried Cable" sign post was called for by station and offset. The sign post was driven directly through the signal conduit by the sign sub-contractor after final landscaping and a light snowfall had covered all evidence of a trench. The designer was on the spot for the repairs, since the work was done according to plan.
A signalized intersection was to be widened and the signals were to be modernized. This required the installation of temporary traffic signals in order to control the approaches during construction. The phasing of construction as shown in the plans necessitated the relocation of the temporary traffic signal poles and signal heads three separate times. Standardized details were used, but the location of the pole guy wires was not shown. The guy wires bracing the temporary poles crossed two driveways on one corner and one driveway of another business at the intersection. In addition, the alteration of the profile reduced the clearance from pavement to bottom of signal head during the second and third stages. The pay item did not cover the movement of the temporary poles or the relocation or adjustment of the signal heads. The construction change order delayed the project, caused a claim for lost business.
The plans called for lighting conduit to be trenched adjacent to the outside roadway shoulder for the entire length of a new freeway project - extending several miles. The conduit was to be trenched at a depth of 30 inches. The plans also called for the placement of subsurface underdrain beneath the outside shoulder for the entire length of the project, outletting every 350 feet and at low points in the profile. The plans considered the underdrain to be part of the subgrade placement and suggested that the underdrains be in place and operational once paving was completed. Since the road was not to be opened to traffic until the interchanges at either end were completed, the lighting was considered to be a late stage item, to be placed from the completed shoulder. The drilled foundations hit a few of the underdrain outlets, but the more costly operation was the repair and replacement of all of the underdrain outlets which the conduit trenched across.
This one was worth over $1 million in 1981, so imagine what it could cost today:
A sewer trench was proposed along the base of a retaining wall. The drainage and the structural designers had not coordinated. The wall was built and the prime contractor left the site. The sub came in and trenched for the sewer as the plans indicated. The base of the wall slid towards the trench and it took millions from the designer's pocketbook to add unattractive soil nails to the face of the wall to keep it in place.
This one was worth over $1 million, and was fortunately caught by the client prior to advertising for bids: The southbound pavement was not tallied in the quantities.
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