Bridge Sized Culvert Replacement in Alberta

One of our bridge sized culvert projects, near Brooks, AB

According to my search of Alberta Transportation’s Transportation Infrastructure Management System (TIMS), there are 11,861 bridge sized culvert structures across the province of Alberta. Of that, 3,796 are managed by Alberta Transportation. The rest are within Counties, M.D.’s and other municipalities. That’s alot of structures, and management of this asset is not a small task.

Consider it another way. If they all lasted an average of 50 years, that would require about 240 bridge sized culvert replacements each year, across all owner agencies. Luckily, there is a strong industry committed to performing this work, however the actual amount of replacements per year are not even close to this number. Granted that is a highly simplified analysis, but replacement of bridge sized culverts is and will remain an important priority for Alberta government budgets.

When replacing a bridge sized culvert in Alberta, the following five phases are involved in the project:

  • Preliminary Engineering
  • Detailed Design
  • Tender
  • Construction
  • Post-Construction

Preliminary Engineering

Near Olds, AB

The first phase gets the project started. It involves performing a site survey to obtain the digital information necessary to complete the project design. The goal of the phase is to determine all of the options and their life cycle costs in order to perform the action which is best for the long term. All of the factors that influence the site are investigated, including flow rates, traffic counts, environmental regulations, corrosion, and so forth, and available options are compiled. The cost of each option is estimated, and the life cycle cost (Net Present Value) is determined.

  • Responsible use of taxpayer funds requires a thorough analysis of all the available options.
  • Site surveys are performed and preliminary drawings are drafted.
  • Hydrology and hydraulics are evaluated using Alberta Transportation’s Bridge Conceptual Design Guidelines to ensure sufficient flow passage while satisfying environmental criteria.
  • Geometric standards and requirements are reviewed to ensure they comply with Alberta Transportation’s Highway Geometric Design Guide and other applicable standards, and consider future growth and design accordingly.
  • An Environmental Evaluation is conducted according to the Terms of Reference for Environmental Evaluations
  • The specifications and recommendations of a Qualified Aquatic Environmental Specialist (QAES) are obtained as required to obtain approval under the Alberta Water Act and/or Federal Fisheries Act.
  • Feasible alternatives are determined, estimated, and hydraulic characteristics and any other relevant criteria are compared side by side.
  • Affected stakeholders and utilities companies are identified and notified.
  • Traffic accommodation / detour options are investigated.
  • Net present value analysis is used to properly compare life cycle costs for the crossing, rather than purely the cheapest option today
  • One option that satisfies the design criteria will be recommended in a Preliminary Engineering Report.

Detailed Design

Following the selection of one option to proceed to detailed design, this phase investigates every design variable and makes design decisions based on Alberta Transportation standards and design guidelines, and engineering judgment. The end result is a set of design drawings, with potentially a detailed design report that itemizes each design consideration, if desired.

  • Upon selection of a design option from the preliminary engineering report, detailed design of the structure and approach roadway commences, including design drawings and an independent design check.
  • Right of way requirements are reviewed and Individual Ownership Plan (IOP) drawings are prepared for use in property acquisition.  Application for a disposition from AEP will be made, if necessary.
  • Environmental applications are made once the design drawings have been finalized.
  • Environmental documents and permit status are input into the Environmental Regulatory Tracking Application (ERTA).
  • Utility agreements are acquired.
  • A Geotechnical Evaluation is performed if necessary.  Bridge Design Bulletin #2 specifies that a Geotechnical Evaluation should be performed if the height of the embankment above the culvert is 6 m or greater, or if poor soil conditions are otherwise known to exist. The Preliminary Engineering Report will address the requirements and implications.  If required, a Geotechnical Evaluation will be completed and the findings will be incorporated into the design.
  • “P” drawings and “C” estimates are prepared using Alberta Transportation’s standard bid item list.
  • The information will be summarized in a detailed design report, which includes the design drawings.

Contract Tendering

Following the design of the bridge sized culvert, the tender is written. The tender has two main parts: The shell (which has generic items like bonding, conflict of interest, and tender submission administrative issue. And the Special Provisions, which contain the site specific specifications for the project. Since most parts of a bridge size culvert replacement project are standardized, the Standard Specifications for Bridge Construction are included in the contract and serve as a fall back specification. Standard specifications are utilized wherever possible, but most of the time some unique, site-specific specifications need to be written.

  • Specifications, regulations, payment clauses and quantities are carefully reviewed to ensure all the correct information is included in the tender document and that all aspects of the work have been addressed and the potential for cost overruns is minimized.
  • The tender document is prepared, and copies of the environmental permits, Environmental Risk Assessment and other supporting documentation are included.
  • The tender package documents are prepared using the PMA Delivery system and submitted to the Strategic Procurement Branch following approval by the Region.
  • Questions and inquiries from Contractors are answered promptly and addendums prepared as necessary.

Construction Management and Contract Administration

Near Cardston, AB

Following the tendering of the project, construction can begin. There are usually a few things that take place prior to mobilization, like Traffic Accommodation Strategies, ECO-plans, and inspection of the culvert at the plant.

  • The construction contract is administered and interpreted to obtain the expected value from the work. The Senior Construction Inspector should be familiar with the design and the contract and will therefore have a strong knowledge of the work prior to construction.
  • Material specifications will be reviewed for compliance.  Contractor submittals including but not limited to the Environmental Construction Operations (ECO) Plan and Traffic Accommodation Strategy are reviewed for compliance in accordance with the applicable standards.
  • Traffic Accommodation measures, approach roads and site detours are inspected.
  • Construction materials such as steel and precast concrete are inspected at the plant prior to delivery and upon arrival to the site.
  • A pre-construction meeting is held between the Consultant, Contractor, and Alberta Transportation.
  • Weekly reports are provided to Alberta Transportation.  A.T. should be notified of important milestones, successes, and/or issues that arise during the work.
  • Alberta Transportation is notified of items of potential cost implications, quantity under/overruns, and issues with Contractors or other stakeholders if required.
  • Progress payments are issued monthly.

Post-Construction Engineering

Near Pincher Creek, AB

From the consultant’s perspective, the project isn’t quite done at the completion of construction. A final inspection is held to ensure A.T.’s satisfaction with the result, and written confirmation is given to the Contractor that the Contract has been fulfilled. The BIM system needs to be updated with the new structure information, and final details of project payment quantities must be submitted for filing. Normally, a final project report is submitted which contains all the project details, as-built drawings, weekly reports, and project paperwork.

  • Final acceptance is issued on Alberta Transportation’s behalf.
  • A post-construction BIM Report and Coding Sheet is completed by a certified inspector and sent to the Regional Consultant for review and entry into the system.

All work must comply with Alberta Transportation’s Engineering Consultant Guidelines for Bridge and Water Projects, Volumes 1 and 2.

It seems like alot, but there are a few consultants that perform many bridge sized culvert replacement projects in Alberta and will ensure there are no hiccups throughout the process.

Please do not hesitate to call Bernie at (403) 942-6170 if you need help with a bridge sized culvert replacement project.

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