As with most majormunicipalities in Canada, Edmonton follows a development model in which privatedevelopment corporations install all local infrastructure and services in newsubdivisions, to construction standards set by the municipality, and inspectedregularly by City inspectors. After a”Construction Completion Certificate” (CCC) is provided at the end ofthe installation, the city-owned utilities (water, sanitary & storm sewers,and electricity) allow connections of the new subdivision to theirnetworks.
The new subdivisioninfrastructure, however, remains the property (and repair responsibility) ofthe private developer for a period of two years. After two years, absentproblems that reveal deficiencies, a “Final Acceptance Certificate”(FAC) is issued that formally accepts the “donated asset” to the Cityof Edmonton, which takes over all responsibility for subsequent repair,maintenance, and replacement.The efforts of the City inspection staff arecrucial to the enforcement of those construction standards. The construction ofthe three “deep utilities” – water, sanitary and storm sewer – is inspected bya single group, the Water & Wastewater Joint Inspection staff. They are called the “deep utilities” becauseEdmonton, along with other inland Canadian cities, has a remarkably deep frostpenetration: up to 2.5m in severe winters. The water-bearing pipes must thus be buried almost 3m deep to avoidfreezing, making the construction of these utilities expensive.
So there is a considerable dynamic tensionbetween the construction contractor, whose profit comes from achieving a highernumber of meters constructed per hour, and the City Inspections staff, whoseresponsibility it is to see that those expensive repairs or replacement neverhave to be done after project delivery. Once a given set of construction standards isagreed upon and published, however, it is well-understood by both sides of thecommunity that the judgment of the City’s inspector is final. But the questionis, is this judgment supported by every level of management of the municipalcorporation? Although most constructioninspectors have considerable experience, some are young former pipemen andtechnicians who must question the work of private foremen decades theirsenior. These judgments are madedaily. It is unreasonable to expectinspectors to do this if they are not certain that they have the entireorganization standing firmly behind them. The author believes that due to lack of enoughsupport from high-level management in the organization the inspection is notdone properly and all the system rely on two years maintenance guarantee periodwhich base on technical evidence is not sufficient.
In Edmonton in most cases dueto economic reason the excavated materials are used for backfilling. Most ofthese materials are clay soil with high plasticity. It is obvious that aftertwo years even after repairing the errors and appeared distresses in thepavement by contractor for getting final approvals, settlements do not stop anddistress causes would remain in underneath of pavement. Settlement in Threemeters of uncompacted clay soil will not stop after 2 years and distresses wouldnot stop consequently.