A proponent is responsible to ensure that, prior to the construction of a new structure for a radiocommunications site, the proponent considers whether there exists a tower owned by another operator on which they could share space. Often such a co-location arrangement requires that the proponent pay for upgrades to the existing tower to achieve the necessary structural profile (within certain engineering limits), and to also pay some amount of rental fee for the use of the space on the tower and building footprint on the ground.
A proponent cannot refuse another proponent use of their tower, and all proponents are required to respond in a timely fashion to requests for co-location. Innovation, Science, and Economic Development Canada (ISEDC) has made compliance with CPC 2-0-17 a condition of license renewal for all operators.
Before 2008, commercial operators, such as mobile telephone operators, engaged in an active practice of infrastructure competition whereby they would not share their tower space with other competitors. This resulted in multiple towers being built in close proximity - one for each operator, and the resulting "antenna fields" created negative visual amenity effects on the local surroundings.
Innovation, Science, and Economic Development Canada (ISEDC) responded to the public complaints surrounding infrastructure competition by requiring all license holders to submit to mandatory tower sharing provisions as a requirement of being granted new licenses or renewing existing licenses.
As a result, a proponent wishing to build a communications tower must first establish that there are no suitable structures available within the area they wish to serve from which they can achieve their signal coverage or capacity objectives. Though an existing tower may not be a "perfect fit" from an engineering standpoint, if the signal strength and coverage over the target area from an existing tower achieves, in large part, the same results as a new tower, a proponent will be expected to utilize the existing structure and suppliment any deficiencies by altering their network design, or show that the combined effect of using the existing structure and supplimentary measures will result in a more intrusive solution than the new tower on the overall area.
In cases where an existing structure is available, and is deemed a reasonable solution, a proponent will make a formal request to the owner of the tower to discuss sharing the tower. If the owner of the tower is a licensed operator, they must provide a Preliminary Information Package (PIP) to the proponent within 30 days of receiving the request so that the proponent may analyse their requirements assuming use of the tower and determine the practicality of placing their antenna system on the structure.
Once the analysis is complete, the proponent will provide their proposed antenna system design to the tower owner for review and will begin negotiating a commercial agreement for use of the tower including any upgrade costs to the tower, rental rates, and land lease provisions.
Some communication tower owners are not licensed spectrum operators (i.e. schools, fixed wireless ISPs operating in non-licensed bands, etc.). While proponents are encouraged to explore these options for co-location, tower owners who are not license holders are not required to share their towers under either CPC 2-0-03 or CPC 2-0-17. As a result, a proponent may have no choice but to build their own structure even where a perfectly viable option exists.