November 05, 2004
On the expansion of I-45

Here's the report on the scheduled public meeting to discuss plans for widening I-45 north of downtown.

TxDOT statistics show that some 224,000 vehicles per day use I-45 inside Loop 610. The average speed of those vehicles is 36 mph.

By 2025, TxDOT estimates that, with no change to I-45, that average speed will decrease to 32 mph along I-45 within the Loop as the number of vehicles that travel that section of the corridor increases to 269,000.

The I-45 high-occupancy vehicle lane, which is used by 7,000 vehicles per day that travel an average of 55 mph, will bog down to 38 mph by 2025 as the number of cars that travel on those lanes increases to 17,000.

As a result of those projections, analysts have concluded that the addition of managed lanes heading each direction along I-45 will most effectively ease traffic along the corridor.

The managed lanes will take up four center lanes in the middle of the freeway between downtown and Beltway 8, then will reduce to two lanes between the Beltway and Texas 242.

Along with serving as two-way HOV lanes, the managed lanes will also be used for two-way bus service, and will be eligible for use by single-occupancy vehicles that wish to pay a toll.

Those changes would expand I-45 from nine to 12 lanes between downtown and the Beltway, from 11 to 12 lanes between the Beltway and FM 1960, and from eight to 10 lanes between 1960 and Texas 242.

I have two thoughts about this. First, as one who travels the three-lane Pierce Elevated every day, any increase in I-45's capacity coming into downtown is just going to make the bottleneck at the onramp from I-10 that much worse. The tailback on I-10 to the one-lane entry point to I-45 South can be a half-mile or longer, with cars slowing down one lane over to swoop into any empty space. I-45 itself from I-10 to the 59/288 exit can come to a screeching halt any time, any day - I've seen it happen at noon on Sunday - especially at the deep valley where the freeway goes under West Dallas Avenue and then makes a steep climb to its above-Pierce-Street elevation, which is also where two entry/merge points, from Allen Parkway and Memorial Drive converge. Extra capacity coming in will just make this worse, but I'm not hearing of any plan to expand this section of the freeway. Given that it would be hideously expensive to do that because it's an elevated highway, I don't expect to ever hear of any such plan. For that reason, and because of its direct impact on me and my daily driving, I will oppose this and any similar expansion of I-45 north of downtown.

Second, isn't the fact that we're even discussing the need to add lanes to I-45 an admission that the Hardy Toll Road is an utter and abject failure? We've got eight lanes of mostly empty highway, running from The Woodlands to Loop 610 two miles east of I-45, yet it apparently has no impact at all on I-45's congestion. Wouldn't it make more sense to take advantage of this grossly underutilized existing capacity instead of spending millions to pour more concrete? Why isn't this a part of the plan? Why doesn't TxDOT just offer to buy out the Hardy from the HCTRA, for whom it must be an albatross, and spend whatever is left over from the I-45 expansion budget to extend the Hardy into downtown? What am I missing here?

Posted by Charles Kuffner on November 05, 2004 to Planes, Trains, and Automobiles | TrackBack

It seems universal that nobody considers conversion points when opening a new road, at least in Texas.

I live along 151 in San Antonio, and I'm thrilled that it's open for-real now. Unfortunately, the increase in speed of everything on 151 has made its merge points horrible. For some reason, they started construction at 151/90 right as they finished 151, taking the two-lane merge to 1, and creating a mile or more of backup every morning. Going north on 1604 from 151 was always ugly, with 3 lights about a mile or so each apart, but now the backups commonly run from one light all the way to the next.

Does anybody ever actually plan how these upgrades will fit with the rest of the dang system??

Posted by: Buhallin on November 5, 2004 10:08 AM

So if I have an eztag and a passenger in the car, do I pay, because it's a toll road or do I not-pay because I'm a high-occupancy vehicle?

Posted by: Michael on November 5, 2004 10:21 AM

I've often wondered what happens to the 12 lanes coming in from Katy when it hits the bottleneck under the loop, too.

I think buying the Hardy is out for political reasons as well as financial ones. Pouring concrete = jobs for Perry supporters; buying an existing road = no new jobs. Also, user fees/toll roads are the done thing back home now, right?

Posted by: Ginger on November 5, 2004 10:26 AM

As much as I miss Houston reading stories like this remind me how happy I am to be living in my Unabomber cabin on the western slope in Colorado rather than working as a courier in Houston traffic.

Posted by: manndan on November 5, 2004 12:34 PM

Before Houston does anything, their civil engineers need to be familiar with Braess's Paradox.

So if I have an eztag and a passenger in the car, do I pay, because it's a toll road or do I not-pay because I'm a high-occupancy vehicle?

I'm just speculating, but I'd bet that if you have an EZTag and a passenger, you'd go to the cash booth and let them wave you through instead of going through the EZTag reader booth.

Posted by: Mathwiz on November 8, 2004 1:34 PM