Timeline of a Civil Engineering Project

In the same vein as the project cost article I did I thought it might be interesting to cover the typical time of a civil engineering project. As part of a program management team on a rail corridor for the past two years I have been exposed to the entire lifespan of several Public Works projects.

Here is an example of what part of an overview-level schedule might look like:

Here is how the process works, from the eyes of someone in the industry. I use the following general rules to develop the baseline schedules for project's when they are just beginning.

Major Project Phases

Preliminary Engineering
Engineering, Environmental Clearance, Right of Entry
Advertise and Award
Close Out


First the project is in the planning stage. Studies are conducted to determine when and if the project should be built, the results of these studies for several projects are compared to see which ones should be built first to be most cost-effective. Extremely rough estimates of cost are thrown around (eg a road tunnel being $30,000/foot for XXXX amount of feet). Projects can be in planning for any number of years. The client I work for has some projects in planning that may not be built until 2040-2050.

Preliminary Engineering (2%)

When the time comes that the project should be implemented, budget is allocated for it (or maybe just for the projected first few years of it) and a consultant is brought on board to do preliminary engineering. The product of this effort is some sort of Project Study Report that includes definitions of the project, it's outputs (both good and bad), a slightly more engineered estimate (eg a road tunnel would be separated into excavation, grading, support structures, pavement costs) but still pretty general. This study is used by the agency to "define" the project. They use it as a "resume" to apply for funding grants with various lenders (FRA, FTA, local government bodies etc.) A more permanent budget may be set using the costs of the study and using the guidelines in the Budgeting a Public Works Project post.


With the initial study done, a DIFFERENT consultant is brought on board to do the actual design. They start with the preliminary report and get cranking.

Basis of Design (2%)

Their first major goal is to submit a Basis of Design report which will state design facts and physical limitations on the project, such as curve X cannot exceed Y degrees, Z grade, and E superelevation, due to obstructions or whatever and any other limitations and guidelines they have to design within. They also state what codes and regulations they will follow in their design.

Alternatives Analysis (10%)

Following the Basis of Design report the design consultant works towards a 10% design level. This is commonly referred to as the alternatives analysis submittal. At this stage they define the main alternatives to the project and provide the most details possible for each. Once completed, several meetings take place between the designers, owners, and all other stakeholders in the project area (transit authorities, interested groups etc). They determine what option is best. In some cases it is a draw between two alternatives and they continue with the design of both.
Usually starting with the 30% submittal, and following with every subsequent one, a very formal review process involving third-party engineering professionals takes place. The review process typically lasts a month or two following each major submittal.


Around this time is when the environmental requirements of the project begin to be defined. In order to get environmental clearance, quite a bit has to be known about the project and surrounding area. Endangered species reports, project impact footprint, biological opinion reports, and many other activities may take place now. The main environmental document for NEPA (federal) and any State regulations for clearance may also begin to take form. Common NEPA documents are Categorical Exclusion (CE), Environmental Assessment (EA), and Environmental Impact Statement (EIS).

30% Design

The designer has continued on with the design(s) of the project. At this point a definite alternative is chosen, rarely do more than one alternative advance past this point. This is also when environmental activities are in full swing and the Draft NEPA document should be being reviewed or possibly already approved.

60% Design

At this point the Final Environmental Document has hopefully been approved. The Final document will outline any extra environmental requirements the project must include in order to be built so it is nice to get it done at 60%. Also at this point it is fairly well defined what properties the project may impact both permanently and during construction. The Right of Entry process should begin now and the owners of the parcels need to agree to let construction go on near and in their property (they are also paid for this). Eminent Domain may be enforced if the project is valuable enough to the community and the owners are being stubborn.

90% Design

Things are really shaping up on the design. Project costs are close to final and the program managers are probably allocating adequate funds for construction of the project.

100% Design

Design is "complete". Following the last review session the design is "conformed" into the bid-ready state. The design is comprised of the Drawings, General Specifications, and Technical Specifications. These are handed over to the client/owner who (in our case) has a contracts department that will review it and get it ready to bid.

Bid Preparation

It usually takes a month or two from the time the final design is handed in until it is ready to be advertised to the bidders. The "package" that the bidders are given takes this amount of time to prepare, check for errors, and have legal counsel also review (there are a lot of opportunities for lawsuits at this stage so attorneys become involved to review everything).


The project is advertised publicly and the prepared bid package is made available to those interested in bidding for the construction work. Questions are asked by the bidders and the owner provides answers back to the public. Everyone must be able to see all questions and answers or you could be opened up for lawsuits.

Bid Opening

Bids are opened a few months (2-4) after advertising. For us the winner is the "lowest responsive, responsible" bidder, and those terms are heavily defined legally so that they can cut the ties to someone who may not be qualified. The low bidder wins automatically if everything checks out, there were no mistakes in their bid, and they are qualified. If the first bidder gets the boot it goes to the second, and then the third etc.


The construction contract is awarded to the main contractor, a construction management consultant is brought on board, and construction work commences!


The project is finally built! This can last from a few months to several years!

Close Out

After the main construction work is complete the contractor is "relieved from work" (legal wording) is paid and congratulated. There might be a "grand opening" at the project site.
But the work is not done! Several things still need to be done, often completed by the construction management consultant. Outstanding payments need to be processed. All of the construction documentation of exactly what was built are combined into the As-Built documents that are kept by the owner. There may be pending lawsuits from contractors that are resolved at this point. Any required long term "mitigation" or "revegetation" period that was required from the environmental permits is also conducted at this point. With all of these things combined, the close-out period sometimes lasts as long, or longer!, than the construction period. Seriously, some close-out periods are five years for a two-year construction project.

When all is said and done a project that takes one to three years to build, is actually a five year project minimum, with ten not being out of the question. For reference, most of the projects I am involved with are rail and rail-improvment projects like new track, new bridges, new stations etc.

About Conrad

I am a Civil Engineer. I work in San Diego and am preparing to take the PE Exam. I am interested in surfing, business, travelling, and spending time with my wife. Thanks!

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