4 things to consider when tendering a stream project

1. Earthworks: Lump sum or volume?

There are two ways you can consider tendering earthworks—importing, moving, or removing soil on site—for your site. First, if your site is simple, clean (i.e., no contaminated soils), and there is a reasonable cut-fill balance, you may want to tender the earthworks as a lump sum item. This means the contractor is provided with the grading plan, cross-sections, and the engineers’ calculation of how much cut and fill there is. Based on this estimate, the contractor provides a lump sum cost to do all the grading. Minor variations in grading during construction to field fit are no big deal—they’re just paid out as part of the lump sum. Larger variations due to unexpected conditions or additional extents of grading can be handled by a change order. 

The second way to tender earthworks is by volume. This method requires accurate estimates of cut and fill to be presented on the form of tender and is paid out based on volumes obtained by site survey. This method is a bit more labor-intensive to manage in the field, both for the contractor and the contract administrator, as volume surveys may need to be completed multiple times for various areas and pay items (e.g., topsoil, grading, subgrade below creek substrate). But when there are earth materials on site that are unsuitable for reuse (not structurally sound or contaminated) then this method is the best and most fair way to tender the earthworks. My preference is to use the lump sum method, and then fall back to the volume-based method if required.

2. Mandatory pre-bid meeting on site

One of the most important things you can do is to have a pre-bid meeting on site with potential bidders, the project engineer, and the client project manager. Having interested contractors physically at the site to review it for flow conditions, access and space constraints, project scale, and proximity to utilities or neighbors will allow them to submit more informed bids. 

A pre-bid site meeting may also allow some contractors to determine that this type of work is not for them, thus reducing your risk that an inexperienced contractor will provide the lowest bid, simply because they do not fully understand the magnitude or intricacy of the project. And although oral questions and answers are never considered official in a tender process, it allows the contractors to communicate directly with the designer, ask clarifying questions, and to better understand the vision for the finished project.

3. Prequalification: One stage or two?

There are a lot of good contractors out there, but not all of them have experience doing stream work. And, as I mentioned above, streams are not the same as roads. Pre-qualification is a process by which I help my client award their bid only to someone who is well-qualified through practical project experience to construct the stream project.

There are two ways to prequalify bidders: in a two-stage or single-stage process. My preferred method is a two-stage process. It works like this: A call is put out to bidders informing them of the project, including a description of the work, and asking them to provide references for projects that involve similar work. Calls to the references determine if the work is similar enough or meets the prequalification requirements. Contractors that meet the prequalification requirements are invited to bid on the project, while contractors that do not meet the requirements are not. 

In a single-stage prequalification process the same reference process is carried out, except that the references and prequalification experience are provided as part of the bid. In theory, this process should work the same as the two-stage process, but it can be hard to convince a client that the low bid does not meet the qualification requirements. I think the two-stage process is cleaner, as it eliminates the potential for bias that may be introduced by knowing the bidders’ costs.

4. Leave some things for the contractor to figure out

Now that contractors have visited the site, I suggest you use their experience and expertise, and allow them to help the project succeed. I incorporate contractor input by having them develop the water management plan for the construction, as well as the sediment and erosion control plan. The contractor can then choose which methods are the most efficient and cost effective for their planned work approach. This gives them the freedom to pipe flows around the work site by gravity instead of pumping, or to use a turbidity curtain instead of a coffer dam to isolate a work area.

To be clear, this method of contractor input is not carte blanche for the contractor to ignore erosion control entirely or to drive excavators up the river. The water management plans and sediment and erosion control plans are developed in consultation with the designer, and they must be approved by any regulatory agencies. The way it usually ends up working within the permitting process is that the agency provides a conditional permit based on receiving and approving the contractor’s plans. Once the plans are received and approved, the final permit is issued, and the contractor can start building. Since I’m not dictating how much silt fence to use, and where the silt fence must be placed, I typically tender the water management and erosion and sediment control tender items as lump sum items. The contractor, knowing their planned approach, can provide a bid price for these items, which are them paid out based on the percentage of the project completed at the time of payment.

Consider these four things as you work through tender preparation and bidding, as they can help your process go more smoothly, and result in well-qualified contractors building your projects. Happy tendering and constructing!