(Source: Reconnect Austin, Heyden Walker)

Houston was the first city in the United States to sink an elevated freeway into a below-grade trench at the same location. The project lasted from 2004 to 2006. It was immense and, at the time, quite controversial. But the section of freeway between Mandell and Spur 527 (approximately Montrose) had exceeded its design life. Something needed to be done. And the community decided to make a long-term investment in itself. Today, US 59 goes through the area, affording commuters easy access from one side of the city to the other with minimal impact on the nearby neighborhoods.

(Source: Reconnect Austin, Heyden Walker)

Breakdown of Construction Costs

Cost of construction (without bridges): $71.1 million (@2004)

CPI adjusted cost of construction: $96,110,110

Length: 9,240 ft.; Width: 192 ft.

Total Square Footage: 1,774,080

Cost per Square Foot

$54

Background Narrative

(Source: TexasFreeway.com)

Since the early 1960s, the 1.75 mile segment of US-59 from Mandell to Montrose has served the major Houston activity centers of Downtown, Midtown, the Museum District, and the Medical Center. It has always been one of if not the busiest stretches of freeway in the world. At first, back in the 1990s, TxDOT planned to address the traffic problem by adding a second elevated deck for HOV to the existing elevated freeway. The nearby neighborhoods, however, protested vehemently against the very idea of the second elevated deck.

TxDOT then proposed replacing the elevated deck being demolished with one that added two mainlanes and an HOV lane. Once again the neighborhoods protested while also demanding that TxDOT trench the elevated freeway below-grade. Why? They wanted to reduce noise and eliminate an unsightly concrete barrier that was dividing a historic neighborhood.

(Source: TexasFreeways.com)

In the end?

(Source: TexasFreeways.com)

Some residents feared commuter traffic would use neighborhood streets. They tried to stop the reconstruction. But TxDOT endeavored to minimize the impacts to downtown traffic, and its efforts were ultimately successful. To accommodate northbound traffic during construction, TxDOT accelerated the construction of exit ramps for Main Street and Polk Street to provide alternatives to the existing West Gray/Pierce Street exit ramp. For southbound traffic, TxDOT reworked construction plans to allow two southbound lanes to remain open during all phases of construction.

(Source: HoustonFreeways.com)

The below-grade trenching of the freeway segment included the construction of four arched bridges (with aesthetic design and landscaping features) over US-59. This section is now called the “Gateway to Houston.” East of Montrose, the freeway regains elevation to connect with the present Spur 527. The original 10 lane facility (five lanes each direction) was expanded to a 12 lane facility to include a two-lane barrier separated HOV facility that diverts from US-59 onto Spur 527.

(Source: HoustonFreeways.com)

In sum? TxDOT managed to sink it in 2 years, without any frontage roads to work with. And today, the daily traffic volume “inside the loop” is over 330,000 vehicles per day – more than twice that of I-35 as it passes through Austin’s urban core! – with traffic flowing relatively smoothly.