No, the Bolin Creek Greenway will not cost as much as building the Big Dig in Boston

Fighting against the wrong information that’s being circulated around Chapel Hill and Carrboro is almost a full-time job. We have fact-checked many claims related to the Bolin Creek Greenway, and are appreciative of the Carrboro Linear Parks Project for creating a FAQ with primary source documents that detail exactly what’s happened so far.

Today we’re going to take a look at the claims about the cost and financial impact that the future Bolin Creek Greenway in Carrboro will have on Carrboro and homeowners.

This fact check originates from an email that circulated over the weekend across neighborhood listservs in Carrboro. We appreciate everyone who continues to forward us inaccurate information seen on neighborhood listservs, which often limit who can post. (We’re at [email protected])

The claim: The greenway may cost up to $82.5 million….

That is an astounding sum. It is just about as much as the Town of Carrboro’s adopted budget for this year. It’s about the cost of creating a mile of highway for the Big Dig in Boston, which involved a considerable amount of tunnels and bridges in a densely-populated urban area. 

It is also sheer nonsense.

If the greenway extension were to cost $82.5 million, this would be by far the most expensive greenway, on a per-mile basis, that we’ve been able to find in the entire United States. The length of the remaining Bolin Creek Greenway segments is 3.64 miles — Phase 2 (0.61 miles), Phase 3 (1.77 miles), and Phase 4 (1.26 miles). (Phase 2 is currently on indefinite hold.)

To take the opponents’ claims at face value, the cost of completing the 10-foot-wide Bolin Creek Greenway in Carrboro (in an existing cleared 30-foot-wide sewage easement) would be more than $27 million per mile. That’s patently absurd and more than 4x what it costs to create a mile of interstate highway. Here’s are some comparable projects:

• In the Town of Cary, the 2,500 foot extension of the Crabtree Creek Greenway Trail is under construction for $1.65 million (with $332,000 paid for by the town, the rest through grants).
• A one-mile segment of Wake’s Middle Creek Greenway is estimated to cost $3.1 million (with funds from various sources).
• The Triangle Bikeway is a project intended to connect Chapel Hill with Raleigh near I-40. One of the seven segments of that project includes 5.2 miles of trail, a bridge over I-885, a tunnel under another road, and includes two additional bridges and three boardwalks. It is estimated to cost between $19.5 and $22 million.

How much is $27 million per mile?

That’s more than the per-mile cost to add two new lanes to I-40 in Orange County and reconstruct all of the interchanges (total of $236 million, 11.5 miles). That’s more than the per-mile cost of Chapel Hill’s 8.2 mile North-South BRT project, which includes the cost of buses, roadway expansion, a multi-use trail along much of the corridor, and stations. We’re hard pressed to think of any linear transportation project that would cost so much. The Big Dig in Boston cost slightly less per mile. It’s comparable to constructing the Oakland Bay Bridge – a project that stretches across the San Francisco Bay and involves building a bridge. Over water.

This is a completely made up number.

The assertion, of course, is that some of these costs might be due to unknown contingencies. But let’s be realistic.  As been noted over and over and over (and over) again, a large portion of the trail will be built atop OWASA’s existing sewer easement that is flat and has already been cleared and graded because large trucks routinely go along it. And, the Town of Chapel Hill (which is right next door!) has extensive experience building greenways along other sections of Bolin Creek. The idea that there will be massive unexpected costs for Carrboro’s segment is a fantasy.

It’s also important to note that before the town will bid out the project, there will be an engineering firm hired to prepare a series of preliminary drawings that will provide a good estimate of the range of costs of the final project. If those cost estimates show the project to be feasible, the engineers will draw up final plans that are ready for bid.

Moreover, Carrboro’s taxpayers will likely only bear a fraction of the costs. There are multiple federal programs that pay up to 80% the cost of a greenway project, such as the Cary’s Crabtree Creek Greenway Trail noted above. The Estes Drive bike-ped project in Chapel Hill has a similar funding split. (And, because this is also floating around: HOAs never pay for greenways – the master plan mentions HOAs in the context of them possibly wanting to sponsor a section of trail, much in the same way the Girl Scouts and Kiwanis do.)

For reference, the cost estimates from the town’s 2009 Conceptual Master Study estimates that the cost to build the remaining phases of the Bolin Creek Greenway will be about $3 million. Those costs did not include potential grading or addressing soil issues, all of which will be examined before construction begins. And, to be sure, there has been significant inflation in the cost of construction since 2009 — which is another way in which the efforts to block construction of the greenway over the past 14 years have been harmful. (We could have had this 14 years ago, and for much cheaper!)

But to claim that the cost has increased by a factor of 20 is unreasonable, particularly in comparison to other projects that are being built right now across the United States.

Update: At the 6/6 Carrboro town council meeting, Linda Haac said that she was using the cost estimate for a project in suburban DC, from Bethesda to Silver Spring, in metro DC, as the basis for her cost estimate of Carrboro’s Bolin Creek Greenway. The DC project involves:

• Creating a lengthy underground tunnel under existing Wisconsin Avenue (6 lanes) and alongside an existing Metro station and active light rail train.
• Creating two trail bridges over existing heavily-trafficked roads (Connecticut Avenue and Colesville Road) and three additional underpasses alongside the route.
• Adding 4-5 miles of path within existing infrastructure alongside the Purple Line project.

Half the costs of the DC metro project are due to creating a tunnel parallel to the transit tunnel and under new buildings.

It is not comparable to paving a 10-foot-wide path in an existing 30-foot-wide sewage easement above ground for a 2-mile stretch in Carrboro. We can look at comparable projects in Cary and Chapel Hill, if needed – all of which had funding through grants and various sources. The projects in Cary and Chapel Hill are about 80 million dollars less expensive than the project in DC, which is expected.

Differences include: Project scope, project location, and project length. The Bolin Creek Greenway, for example, is not a tunnel project built underground in the busy Washington DC metro area alongside the Purple Line Metro and underneath 6 lanes of Wisconsin Avenue.

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