The installation of the concrete filled jute bag headwalls, unless otherwise specified, shall be provided in total compliance with the Items included in the “STANDARD SPECIFICATIONS FOR ACCESS BRIDGE CONSTRUCTION”. These are attached to the back of this specification and labelled Appendix “REI-C”. The Contractor shall comply in all respects with the General Conditions included in Item 4 and the “Typical Concrete Filled Jute Bag Headwall End Protection” detail also shown therein.
XII. BENCHMARKS
Also, for use by the Contractor, we have established a number of Benchmarks along the course of the work for the Cahill Drain – Upper Part, as shown on the plans. The Contractor shall work with the City Drainage Superintendent or Consulting Engineer or their Inspector to transfer the benchmark as necessary to be used in setting the drain and pipe design grades.
For each of the bridge replacements and new bridge, the plans include details illustrating the work to be carried out. For each bridge detail a Benchmark has been indicated and the Elevation has been shown and may be utilized by the Contractor in carrying out its work. The Contractor shall note that in each case a specific design elevation grade has been provided for the invert at each end of the pipe in the table accompanying each detail. The table also sets out the pipe size, materials, and other requirements relative to the installation of the culvert structure. In all cases, the Contractor is to utilize the specified drain grade to set any new pipe installation. The Contractor shall ensure that it takes note of the direction of flow and sets all pipes to assure that all grades flow from east to west to match the direction of flow within the drain. The Contractor’s attention is drawn to the fact that the pipe invert grades established herein provide for the pipes to be set at least 10% of their diameter or pipe rise below the existing drain bottom or the design grade of the drain, whichever is lower.
XIII. ANCILLARY WORK
During the course of any work to the bridges and enclosures along the length of the project, the Contractor will be required to protect or extend any existing tile ends or swales and connect them to the drainage works to maintain the drainage from the adjacent lands. All existing tiles shall be extended utilizing solid Big ‘O’ “standard tile ends” or equal plastic pipe of the same diameter as the existing tile and shall be installed in accordance with the “Standard Lateral Tile Detail” included in the plans, unless otherwise noted. Connections shall be made using a manufacturer’s coupling where possible. Wherever possible, tiles shall be extended to outlet beyond the end of any access culverts. When required, openings into new pipes shall be neatly bored, saw cut or burned with a torch to the satisfaction of the City Drainage Engineer or the Consulting Engineer. All cuts to steel pipes shall be touched up with a thick coat of zinc rich paint (Galvicon or equal) in accordance with the manufacturer’s recommendations. For other connections, the Contractor shall utilize a grouted connection. Grouted mortar joints shall be composed of three (3) parts of clean, sharp sand to one (1) part of Portland cement with just sufficient water added to provide a stiff plastic mix, and the mortar connection shall be performed to the full satisfaction of the City Drainage Superintendent or the Consulting Engineer. The mortar joint shall be of a sufficient mass around the full circumference of the joint on the exterior side to ensure a tight, solid seal. The Contractor is to note that any intercepted pipes along the length of the existing culverts and enclosures are to be extended and connected to the open drain unless otherwise noted in the accompanying drawings.