Dallas Has Too Many Damn Roads

Eric Haney
6 min readSep 3, 2022

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The City of Dallas does not have great roads. They tend to have the reputation of…swallowing your car in a pothole. The City is constantly behind on maintenance and it’s only getting worse. Adding insult to injury (literally), Dallas is also one of the most dangerous urban areas to drive (or walk or bike).

In 2021, the taxpayers of Dallas spent roughly $300 million out of tax dollars for road maintenance — this equates to nearly $600 dollars per household, but its still not enough. The 2017 Bond Program took on another $500 million, mostly for maintenance programs. Staff is already clamoring to get more dollars in the proposed 2023 Bond.

At some point, you have to wonder if it will ever be enough. If you had a friend that owned a house and every time something broke they couldn’t afford to fix it without going into more debt, you question the sanity of the situation. Either they, A) save more money for repairs or B) downsize into something they can afford to maintain.

Dallas already has one of the highest property tax rates in the state, which has one of the highest property tax rates in the country. Taxpayers are already paying enough. I believe this is an issue with an Option B solution — Dallas needs to right-size its roads, for a multitude of reasons.

The Thoroughfare-Arterial-Stroad Life

Dallas’s road network has a foot in multiple generations of transportation planning. In one, there is a relatively consistent grid of streets throughout most of the city (except the newest portions, developed post WW2). In another, we have interstate and tolled highways — lots of them. These highways serve both local and thru traffic and have their own flaws, but their funding and control go beyond the City, so I’m excluding them from the current conversation. Somewhere in the middle of these two worlds is a strange hybrid, the arterial — bigger, wider roads that form the backbone of moving cars around the city, connecting neighborhoods, businesses and tying into the highway system. Think Preston, Northwest Highway and Lemmon.

Arterials are so important in Dallas, they get their own detailed plan — the Thoroughfare Plan, which says which roads get the designation and how they will be designed. Despite its role in shaping our city, the Plan has not been materially addressed since 1993 and many of the assumptions have driven us to the state we are in today.

One of the main issues is the built-in preference for speed over all other factors: cost, safety, land use, and pedestrian / bike traffic. The Plan references Level of Service (LOS) — a metric introduced and made ubiquitous by the Highway Capacity Manual. In short, designing for LOS A means traffic (should) be free flowing, where LOS F means all cars are bumper to bumper, at least during rush hour. The numbers in the Thoroughfare Plan are heavily weighted towards expected LOS A traffic across our arterials. LOS as a design metric has been shown to be flawed in urban environments, but I’m going to keep its use for continuity with the existing policy. Let’s see what this type of system gets us…

A Case Study: Northwest Dallas

For illustration purposes, I’m going to focus on the part of town I am most familiar with: Northwest Dallas. I willbound the conversation between Forest to the North, Preston to the East, Northwest Highway to the South and Denton Drive to the West. Some details:

  • 15 square miles of area
  • 40 miles of arterials identified in the Thoroughfare Plan
  • 80,000 people / 30,000 households
  • Includes Webb Chapel, Forest, and Northwest Highway — three streets which are responsible for a majority of serious injuries and deaths and make an appearance on the Dallas High Injury Network
Dallas High Injury Network

Arterials in this area are comprised of 6 travel lanes (3 in each direction) and a central turn lane. According to the Plan, these arterials are designed for 15–30,000 vehicles per day and actual traffic volumes on these arterials are mostly between 15–30,000 vehicles per day. Generally, they have had stable (or falling demand) as far back as the ’90s which is when the historical counts start.

Each arterial section lasts approximately 15 years between major replacement, so we would hope on average, we would have between 2 and 3 miles of arterial replaced each year in this area. Unfortunately, we are not even close. The last bond program amounted to 2.74 miles of arterial repaired or replaced in the area — roughly the right number, but spread across 5 years.

At this rate, we are spending 1/5 what would properly be required to maintain the arterials we currently have.

Either we increase our spending (and therefore our taxes and / or debt levels), OR we look to reduce our maintenance requirements to something we can afford. Again, I’m going with Option B.

In order to do this though, you have to question the assumptions in the Thoroughfare Plan —put simply, does Walnut Hill between Marsh and Webb Chapel need to be six travel lanes and one turn lane for the city to function correctly? The last traffic count from 2019 saw 18,000 vehicles per day on this stretch. The most up-to-date professional guidance I could find suggests the following capacities if you are willing to accept some congestion at rush hour:

  • 2 lane (w/ left turn lanes): 18,300 vehicles per day
  • 4 lane (w/ left turn lanes): 36,800 vehicles per day
  • 6 lane (w/ left turn lanes): 55,300 vehicles per day

This section of Walnut Hill is definitely oversized, and potentially WAY oversized. We’re paying for six lanes while we really only need two. You could eliminate the other lanes and have no meaningful impact to traffic. During a months-long lane closure due to a water main replacement at Bowman (which intersects Walnut Hill) this was confirmed. There was no backup, no gridlock — only a temporary slowdown as cars merged. It almost slowed down cars to the posted 40 mph speed limit.

NW Dallas Traffic Volumes from 2000 to Present

Walnut Hill is not an outlier. Arterials across the area could be reduced to four, and in some cases, two travel lanes. There are millions of dollars being spent on excess roads, or conversely, millions of dollars not going to proper upkeep of the lanes we do need, nor other modes of travel which take people off our arterial grid (i.e. walk, bike, transit). Only Northwest Highway appears to necessitate our current standard of 6 travel lanes. It should be noted, grimly, that this section of Northwest Highway, through dense residential and skirting Bachman Lake, also kills and injures enough people to be on the Top 15 most dangerous streets in Dallas. Reducing injuries along this stretch will truly require Dallas to prioritize safety first, even if that means noticeable compromises to free-flowing traffic.

Any End in Sight?

A recent lane-elimination experiment in Oak Cliff, prompted by a pedestrian death, is a useful data point for a path forward. Concerned citizens worked with the transportation engineers to remove one lane in each direction (from six total to four) with traffic cones. The results were as expected — due to its overbuilt size, the lane reduction did not affect volumes or even speed outside the margin of error. It did, however, reduce accidents 82% during their study period.

Continuing to take on debt to maintain arterial lanes we don’t need and that make our neighborhoods less safe is terrible policy and it needs to change.

My Suggestions on Improving the State of Dallas with a Focus on Arterials:

Today: Improve Arterials Now

  • Provide temporary lane closures and impact studies on most egregiously-oversized arterials
  • Provide temporary lane closures and impact studies on arterial sections noted in the Vision Zero High Injury Network

Tomorrow: Amend the Thoroughfare Plan

  • Increase the design capacity of arterials to be in line with a lower grade Level of Service from current engineering standards
  • Require re-investigation of current traffic counts against designed capacity before replacing an arterial
  • Explicitly state Safety over Level of Service or Speed as the top priority in high-pedestrian areas

The magnitude of this problem across the city is both a blessing and a curse. The curse is that arterials, as currently enacted in Dallas, are a boat anchor of cost and injury that we can longer afford. The blessing is that any change, even a small one, will be noticeable. For the price of traffic cones, we can become a more prosperous, resilient and safer city. If we choose to instead invest our right of way into space for walking, biking, transit, or trees, we could wake up in an even better Dallas.

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Eric Haney

Analytics professional, aerospace engineer and urban planning advocate