INDOT has issued a consulting RFP for the widening and reconstruction of I-465 in the northeast corridor (this is RFP 07-09-s1 – I can’t deep link to these documents for some reason). This includes the 82nd St. interchange on I-69. They actually released this a few weeks back, but I’m just now being able to analyze it. Even more so than with other RFP’s, the supporting documents for this one are a treasure trove of information. Be sure you are on a super-high speed connection and snarf away. The documents of primary interest will be the Feasible Alternatives Selection Report (dated September 2007 – so hot off the presses) and the two associated Preferred Alternative Aerial View documents.
Currently the RFP anticipates construction spanning four years from 2010 to 2013 with a price tag of $587 million. The consulting fees alone are estimated to be $40-50 million. However, part of the RFP specifies a consultant who will accelerate construction where feasible.
I haven’t digested the many documents in full, but here are a few findings and observations.
- I-465 wil feature four continuous through lanes in each direction, with one or two auxiliary lanes between interchanges. I believe this is a serious mistake. Obviously, INDOT has to match the four lane cross section south of the I-69 interchange. But from I-69 to US 31, there should be five continuous through lanes in each direction, plus an auxiliary lane between interchanges. If there is room for up to two auxiliary lanes, there is room for a fifth through lane. Yet again, INDOT proposes the absolutely minimum possible improvement in through capacity.
- The Keystone Ave. interchange is a simple partial cloverleaf. This needs immediate reconsideration. With Carmel building roundabout interchange, this design would leave Indy with the ridiculous situation where Keystone is effectively a freeway from both the north and south, but has a stop light at an interstate interchange. The RFP specifies “considerations for unique interchange designs”, so let’s hope they get creative here. The Rockville Rd. options that I highlighted previously were more creative than this. In particular, I think INDOT should look at some sort of three level interchange that would allow both I-465 and Keystone to be free flowing. This could be either a three-level roundabout, or a volleyball style interchange.
- Allisonville Rd. would also be a partial cloverleaf. I had previously said a SPUI might be best, but the consultants studied this and found the partial cloverleaf design superior.
- The best part of all of this is the I-69/82nd/I-465 interchange. I believe this mostly a great design that accomplishes what I’ve been advocating all along, namely complete separation of I-465 bound traffic from 82nd St. bound traffic on I-69. What INDOT does is puts I-69 into a 14-lane configuration: 3/4/4/3, similar to the Dan Ryan Expressway in Chicago. (Incidentally, the 401 in Toronto is a 4/4/4/4 configuration). The center four lanes diverge to/from I-465, two lanes in each direction. The outer three lanes are a C/D system carrying traffic to/from 82nd and Binford Blvd. Ramps from the C/D lanes allow traffic from 82nd St. to access I-465 to/from all directions. As today, not all movements are supported in the interchange. The northbound Binford to southbound I-465 movement as well as the reverse are missing. The study found that traffic would be very light on these movements, only a few hundred cars a day, and insufficient to justify the pain including them would cause. I believe access could be maintained via a partial tight diamond interchange at 75th St., but this would result in several residential relocations. You can see how this works in the aerial photos. I didn’t do this, but it might be good to print them out and paste them together.
- In justifying not adding the two missing directional movements, Corradino lets slip that I-465 south of the interchange would still be congested in the design year. I have been saying all along that four through lanes in each direction was not enough, and sure enough I was right. Too bad INDOT built the 56th St. bridge so narrow that new lanes can’t easily if ever be added under it without prohibitive expense.
- The 82nd St. interchange largely remains as is, a folded diamond.
- The flyover ramps to I-465 from I-69 actually don’t change that much. In fact, the current dual lane flyover from I-69 to I-465 south will be pretty much reconstructed as is.
- The RFP also mentions concern for “corridor aesthetics”. Let’s hope so.
- I consider the near $600 million price tag of this a good sign. This is higher than previous estimates and indicates a more serious project is contemplated.
As I said, there is a huge amount of information in there and I haven’t digested it all. Keep in mind that these are just preliminary observations. My thinking on this corridor has evolved quite a bit. I originally faulted Corradino during the MIS back a decade ago for being to grand in their plans. Today, as much as it pains me to admit it, I’m actually more in line with Corradino’s thinking. I’m sure it will keep evolving over time as I learn more.