What to Expect
Overview:
Each landowner can expect a sequence of events leading up to and during construction on their property that will roughly unfold as follows:
Landowner Agreement
The first step in preparation for construction will be to reach an agreement with each landowner on how the transmission line can traverse the property and what compensation is appropriate for that right. In arriving at that agreement, a landowner can expect to speak with one or more of the following:
- A licensed land agent to address remuneration for the use of and access to the property.
- Experts in agricultural systems to mitigate any impacts to farming operations, such as irrigation infrastructure, that may be caused by the transmission line.
- Environmental experts to minimize the environmental impact of the transmission line and supporting poles, and ensure MATL adheres to its environmental obligations.
- MATL’s EPC (engineering, procurement, construction) contractor who will evaluate the input of the landowner as well that of the environmental and farming system experts to determine the optimal design of the transmission system and final pole location.
Construction Agreement/Land Form
Before the contractors can commence their work, discussions will take place between MATL and the landowners about where, when and how the right of way may be used during construction. These discussions will cover the sequence of events that will take place during the construction process, any impositions this will place on the property and farming operations, and the measures that need to be taken to keep the landowner financially whole. This will be documented, clearly identifying the landowner’s rights and MATL’s obligations, including:
- Land access constraints, both on and off the right of way.
- Temporary works including gates, berms, culverts, access roads, etc.
- The type of vehicles that will be permitted on the property.
- Compensation from MATL should there be impacts that can’t be mitigated including compensation for any lost farming income resulting from the construction operations.
The fundamental principle underlying any agreement reached with a landowner, in relation to construction access, is that the property will be returned to its original condition when the works are finished (except where this is not possible, in which case, suitable compensation will apply; e.g. crop loss).
The Five (5) Phases of Construction
Construction will be scheduled to minimize impact, particularly on the most environmentally sensitive sites. Each phase of construction will be completed sequentially by specialized crews including: survey, assembly, excavation, erection, clipping and restoration. There may or may not be a continuous presence of construction personnel on the property during this process.
1. Right of Way Review and Preparation
Qualified specialists will perform site-specific inspections including topographical and geotechnical surveys. Topographical surveys establish the shape of the terrain, allowing poles to be placed and sized in such a way that proper safety clearances are maintained. Geotechnical surveys assess the soil type where the poles will be installed. This information is used to determine pole foundation design including to what depth the pole needs to be placed in the earth. Topographical surveys involve little if any impact on the land, but geotechnical surveys do require drilling with equipment and will only be undertaken with the prior consent of the landowner.
The location of poles is staked out in advance. This allows for final input from landowners, a subsurface assessment to locate potential obstructions such as buried gas lines, and the confirmation of surface features and clearances.
Before poles are installed the property will be prepared to allow access by construction vehicles. This may include temporary access-gate and culvert installation, construction of temporary approaches, route grading and the laying of gravel where required. All site preparation work is done in accordance with landowner agreements.
2. Material Procurement and Delivery
Transmission poles will be pre-cut, pre-drilled, and delivered to several staging areas along the route of the transmission line. Pole assemblies will then be hauled to each structure location using tractor trailers or trucks equipped with cranes for unloading.
3. Tower Installation
Wooden H-frame structures or long- or short-span steel monopoles will be erected at their design spacing along the transmission right of way. The installation of each type will be quite similar; an auger truck or similar piece of equipment will excavate the appropriate hole or holes in the ground. An hydraulic crane will then be used to raise the pre-assembled structure vertically and place it in the ground. Backfill will be gravel, a dry gravel and cement mix, or concrete, depending on the foundation design.
In some instances guy wires will be installed. These provide additional support to angle and dead-end structures. They splay out in a pattern around the tower on the opposite side to the force they are designed to counter. This varies depending on the geometry of the transmission system at that location. Guy wires are made of galvanized steel and are fixed to the ground using steel screw-in anchors. Protective barriers may be installed if required.
4. Wire Stringing
The conductor cables that will carry the electricity are installed using specially-designed tension-stringing equipment. Temporary “puller and tensioner” sites will be located four to six kilometers apart along the transmission route. These are used to pull the conductors into the right position for installation. Anchors hold the equipment in place while the conductor is pulled tight. Once the correct tension is achieved, clipping crews remove the stringing blocks used during installation and clamp the conductors in place at the end of the insulators.
Five wires are strung from H-frame structures: three conductors, one overhead ground wire and one optical ground wire (“OPGW” - a combination ground wire and fiber optic bundle, the latter used for system monitoring and protection). An overhead ground wire is not used on monopoles, and so only four wires are strung on these structures.
5. Clean-up and Reclamation
When construction is finished, MATL will return the land to its original condition or compensate the landowner fully where this is not possible; for example, if crops are damaged. This may involve re-grading or re-tilling, removing temporary works and surplus soil, re-seeding, and repairing fences and gates. The degree of reclamation required will vary depending on the season of construction.