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Study of Adequacy of Commercial Truck Parking Facilities

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6.0 SUMMARY AND CONCLUSIONS

6.1 Study Summary

Section 4027 of the TEA-21 requires:

…a study to determine the location and quantity of parking facilities at commercial truck stops and travel plazas and public rest areas that could be used by motor carriers to comply with Federal hours of service rules. The study shall include an inventory of current facilities serving the National Highway System, analyze where shortages exist or are projected to exist, and propose a plan to reduce the shortages.

This report, which has been prepared in cooperation with research entities representing motor carriers, the travel plaza industry, and commercial motor vehicle drivers, presents the findings of the Section 4027 study. These findings include results of a national driver survey, estimates of truck parking demand generated by a demand model, estimates of truck parking supply generated by a national inventory of truck parking facilities, and comments and recommendations on the issue of truck parking from State partnerships and national stakeholders. Sections 2.0 through 5.0 of this report describe the detailed results of this study, which are summarized in the list below:

• Only 11 and 34 percent, respectively, of truck drivers surveyed in the national driver survey indicated that they frequently or almost always find parking available at public rest areas and at commercial truck stops and travel plazas. Nearly half reported rarely or almost never finding available parking at public rest areas. Fewer than half of the truck drivers indicated that they frequently or almost always find any of the following features at truck parking facilities: parking convenient to the highway, parking facilities with the needed amenities, parking that allows adequate time, parking with enough room to drive in and out, and parking spaces used only by trucks. For each feature, about 40 percent of respondents indicated that they sometimes find that feature, and the remainder indicated that they rarely or almost never find that feature. The survey results indicate that truck drivers do perceive that there is a problem with the adequacy of available truck parking.
• An analysis of the driver surveys indicated that drivers prefer commercial truck stops and travel plazas for most activities that require them to park, but they prefer public rest areas when stopping for taking a quick nap. Weighting these results by the relative time spent on each activity indicated that 23 percent of the demand for truck parking is at public rest areas and 77 percent of the demand is for parking at commercial truck stops and travel plazas. This split is a key element in understanding the adequacy of truck parking because in many areas where there is an apparent shortage of spaces at public rest areas, there is an apparent surplus at commercial truck stops and travel plazas. One way to address the shortage of public parking spaces is to take steps to shift the demand to the available private spaces.
• The national survey of truck parking spaces identified 31,249 spaces at 1,771 public facilities (e.g., public rest areas, pull-offs, and weigh stations) and between 167,881 and 284,601 spaces at 3,382 commercial facilities. The demand model estimated a total demand for 66,067 spaces at public facilities and 221,249 spaces at commercial facilities. While the estimated demand for parking spaces at public facilities far outstrips the supply, the supply at commercial facilities seems sufficient to meet the current demand.
• A total of between 182,225 and 288,995 parking spaces was identified along Interstate highways, compared to an estimated demand for 245,389 truck parking spaces. A total of between 16,558 and 26,855 parking spaces was identified along non-Interstate highways, compared to an estimated demand for 41,927 spaces. The total supply of parking spaces along Interstate highways seems to match the estimated demand, while the total supply along non-Interstate highways falls far short of the estimated demand. Part of the discrepancy along non-Interstate highways may be accounted for by the greater access to other locations at which to park (e.g., restaurants and shopping malls) along non-Interstate highways than along Interstate highways.
• An analysis of the supply and demand for truck parking indicates that 35 States have a current shortage of parking at public facilities, while only 8 States have a shortage at commercial facilities, and 12 States have a shortage when both types of facilities are considered together. In some cases, the apparent shortage may be mitigated by regional factors (e.g., Delaware could be considered a “pass-through” State, and the parking shortage in Delaware may be offset by parking surpluses in nearby States). In other cases, however, no apparent mitigation exists.
• The growth rate of demand for truck parking was estimated to be 2.7 percent annually, while the growth rate of supply of public spaces was estimated to be 1 percent annually, and the growth rate of private spaces was estimated to be 6.5 percent annually. These estimates suggest that, if other factors that affect truck parking remain the same, the apparent shortage of spaces at public rest areas will worsen while a growing surplus of spaces at commercial truck stops will develop.
• A few States restrict parking (e.g., place time restrictions for parking) at public rest areas, which can further exacerbate any supply shortages that may exist for parking at public facilities. At the same time, some States augment the parking spaces available at public rest areas with parking spaces at other public facilities such as weigh stations.
• A number of factors indicate that the degree to which truck drivers use parking spaces at public rest areas and commercial truck stops and travel plazas interchangeably is limited. Responses to the driver survey indicate a preference for different facilities, depending on the reason for the stop. Field observational studies noted that parking spaces at public rest areas often fill up sooner than spaces at commercial facilities. The study team believes these differences arise for the following reasons: public rest areas typically offer more convenient access to the highway and more certainty of whether a parking space exists (because drivers can often observe the lot from the highway), while commercial truck stops and travel plazas typically offer more amenities. One way to shift demand from public rest areas to commercial truck stops and travel plazas would be to increase the convenience and certainty of finding parking spaces at commercial facilities.
• Geographically, truck parking shortages appear to be more common in the Northeast and the Midwest.
• A number of recommendations for addressing truck parking shortages were proposed by participants in the Rest Area Forum, national stakeholders, and State partnerships. Most of these recommendations fall into one of the following six categories: expand or improve public rest areas, expand or improve commercial truck stops, encourage formation of public-private partnerships, educate or inform drivers about available spaces, change parking enforcement rules, and conduct additional studies.

Although there is a consensus that the adequacy of truck parking is an important issue that must be addressed, there is wide disagreement both among the various stakeholder groups and among the States about the best approach to addressing the problem. Although the problem has national consequences, both the problem and the proposed solutions seem to be more local in nature. For example, some States have an apparent shortage of parking spaces while nearby States have an apparent surplus, and any shortages that do exist are often concentrated on a few sections of highway within a State. The solutions, too, can be local in nature, with some States proposing to leverage existing ITS initiatives to broadcast parking information, others proposing to open more parking facilities, and others relying on private industry to meet the demand. One point of agreement, however, is that the various agencies, organizations, and special interest groups worked together as part of the State partnerships and want to continue to work together to address this issue.

6.2 Interpretation of the Summary and Conclusions

The previous sections of this report provide detailed information about the adequacy of truck parking on the NHS. These results, when presented and viewed as a series of snapshots, tell only part of the story. Missing from that type of snapshot presentation is the bigger picture that surrounds the adequacy of commercial truck parking facilities serving the NHS. To wit: Is there a truck parking problem, and if so, what should be done about it? This section looks at the bigger picture by posing a series of questions whose answers are key to understanding and addressing the adequacy of truck parking and suggesting answers to these questions that are synthesized from the report findings. In particular, nearly all of the suggestions identified below are restatements of recommendations made by the State partners for the express purpose of establishing a starting framework for considering solutions to specific truck parking problems.

6.2.1 What problems are associated with an inadequate supply of truck parking spaces?

An inadequate supply of truck parking spaces can result in two negative consequences: (1) tired truck drivers may continue to drive because they have difficulty finding a place to park for rest, and (2) truck drivers may choose to park at unsafe locations, such as the shoulder of the road and exit ramps, if they are unable to find available parking. Both of these consequences generate a safety hazard for the truck driver and for other drivers using the NHS. However, any program meant to address the problems of an inadequate supply of truck parking spaces must concentrate on a number of issues beyond simply providing additional parking spaces. For example, a Federal program that simply earmarks funds for each State to build new truck parking may not completely address the “big picture” need. Earmarking funds for every State may not be necessary if some States already have a sufficient supply of truck parking. Also, building spaces that have neither the convenience nor the amenities necessary to convince a truck driver to use the spaces would not help; tired truck drivers would either continue to drive to locate spaces with preferred amenities or would park in unsafe locations because of the greater convenience. Finally, parking spaces need to be adequately spaced so that a surplus of spaces is not developed in a select group of locations while other roadway segments continue to have an inadequate supply of spaces. Consequently, the analyses and conclusions in this report will regularly refer back to these issues.

6.2.2 Is there an adequate supply of truck parking spaces for the NHS?

In determining whether the supply of truck parking spaces is adequate, it is important to evaluate not only the total supply of truck parking, but also the distribution (i.e., Are spaces located at the places necessary to meet demand?) and type (i.e., Will truckers use the spaces?) of those parking spaces.

A key issue is to determine what types of parking spaces are available. That is, do the available spaces have the convenience and amenities necessary so that the driver will choose to use them? If these spaces do not meet the needs of a driver, the driver may choose to either drive tired or park on the shoulder. This fact leads to another key element in addressing this problem: a proposed solution must not only consider the number of available spaces, but must also consider the factors that influence truck drivers’ choices about where and when to park.

A second key issue is to determine whether the distribution and spacing of parking spaces address the factors that impact the need for these spaces. For example, an important factor impacting the demand for truck parking spaces is the HOS regulations, which place strict limits on the number of consecutive hours a truck driver may drive. If a driver has “used up” his hours, she/he is forced to either violate these regulations or find a place to rest. If there are no legal parking spaces available, the driver must either park at an unsanctioned location (e.g., an exit ramp) or continue to drive until a parking space is located. Similarly, a very tired driver must either find a parking space immediately or continue to drive while tired. This leads to the following observations about the truck parking problem with respect to distribution and spacing:

• The problem of truck parking is, by its very nature, a local problem. A State or highway that has sufficient parking spaces, in general, can still have important stretches of highway with inadequate parking.
• In the absence of an extreme abundance of truck parking spaces, the factors that influence truck parking must include some flexibility to alleviate truck parking problems. For example, because HOS regulations (or fatigue) place strict limits on the amount of time a driver may drive, drivers must have some flexibility in where they park. It may be safer for a highly fatigued driver to take a short nap on an exit ramp than to continue to drive. On the other hand, a driver who habitually parks on exit ramps may pose a greater safety hazard to himself and the general public than one who drives so as to avoid the necessity of parking on ramps.

The driver surveys, field observations, and demand model calculations all support the conclusion that there is a shortage of truck parking spaces at many locations in the United States and that this shortage is worse for parking at public rest areas than at commercial truck stops and travel plazas. Shortages also appear to be worse for non-Interstate highways, though the fact that those highways are often not access-controlled makes it more likely that other types of parking spaces (i.e., not at public rest areas or commercial truck stops or travel plazas) are used as supplemental parking.

The demand model provides a useful method for identifying locations at which parking shortages may exist, but further investigation is required to confirm the implications of the demand model. For example, the demand model does not consider the fact that demand generated in one section of a highway can often be safely met by supply in a nearby section or that a driver who is getting tired might stop early to park at a favored facility. Also, the demand model does not consider a number of local factors that can influence demand, such as a higher rate of parking near major distribution centers. Further research and refinement of the demand model could help sharpen the demand estimates made with the model. In the meantime, it should be used as only an indicator of potential shortages.

Finally, there is the question of the type of parking (public or private) that is available. Many field surveys have observed that drivers choose to park at overcrowded public rest areas or on the shoulder when parking is available at a nearby commercial truck stop or travel plaza. This could be caused by the uncertainty of finding parking at a nearby truck stop, the relative difficulty of entering and exiting a truck stop, or some other reason. If steps are taken to reduce the factors that make some truck drivers favor parking at public rest areas (or even on shoulders), then the commercial truck stop industry can be effective in addressing the need for truck parking. However, as long as truck drivers view these types of parking spaces differently, a need will exist for both types of parking spaces.

6.2.3 Is it appropriate for the State and Federal governments to take steps to address any inadequacies in truck parking, if they exist?

Even if there is a shortage of truck parking spaces, it may not be the responsibility of the State or Federal government to address the problem. Certain stakeholder groups have argued that expanding public parking for commercial vehicles amounts to a subsidy of the trucking industry and unfairly penalizes the commercial truck stops that serve it. Parallels have been drawn to the aviation industry, where Federal HOS regulations limit pilot flying time, but the Federal government does not help provide sleeping facilities for the pilots.

The other side of the issue is that tired truck drivers pose an imminent health risk to other drivers on the road and that governments have a prevailing interest to protect citizen-drivers by helping tired truck drivers find rest. This view is supported by the existence of citizen-led organizations that are lobbying the government to address this problem and by the media attention that this problem has drawn.

The clearest indication of whether the government has a role to play in addressing this issue comes directly from the comments of the stakeholders interviewed for this study. While different stakeholders prefer different roles for government, ranging from leveraging ITS technologies to better disseminate information about available parking spaces to building more and better public parking facilities, most stakeholders do agree that government should play a role. For example, a large number of State partner groups advocate a hybrid approach that involves the commercial industry working with the State and/or Federal government to help solve the parking problem.

6.2.4 How can locations with inadequate truck parking be identified?

The first step in alleviating parking shortages is to identify the locations at which those parking shortages exist. The demand model and supply inventory represent a good first step in achieving this goal. The primary limitations of this model, however, are that it does not consider a number of local factors that can affect local demand (e.g., proximity to distribution centers that results in truck drivers staging at parking facilities, proximity to other parking facilities that absorb demand, and consideration of travel patterns that affect the short-haul/long-haul ratio). Because of these limitations, the model should be used as a guideline for identifying possible locations of parking shortages that can be evaluated more carefully through additional study and field observations.

As a first step in this process, State governments can use their knowledge of local conditions to refine the model for local usage. For example, the model may estimate that the parking supply for an important North-South travel corridor is “at capacity.” Because the route of interest is an important long-distance travel corridor, however, the proportion of long-haul vehicles on the route is likely higher than that used in the model, which will result in a greater demand than that estimated by the model. Alternately, a route between two nearby population centers may generate an unusually high amount of short-haul commercial traffic, which will result in a smaller demand than that estimated by the model. In each case, model parameters can be calibrated specifically for these routes in order to generate more accurate demand estimates.

Once locations with possible shortages have been identified, field observations can be used to verify the shortage prior to implementation of any expensive plans to address the perceived shortage. These field observations should note not only signs of over-utilized parking facilities (e.g., parking above capacity at public rest areas and parking on shoulders), but also under-utilized parking facilities that may be nearby. Many field studies have already identified situations in which public rest areas were full and overflowing and trucks were parking on shoulders and exit ramps, but capacity still existed at nearby commercial truck stops and travel plazas. To identify the most cost-effective solution to a local truck parking problem, the field observations must identify existing resources that might be used to address the problem. Useful resources might include under-utilized parking at commercial truck stops and travel plazas; VMSs, radio broadcasts, and Intelligent Transportation Technology (e.g., Global Positioning System) to deliver real-time parking information and other public facilities on the highway (e.g., park-and-ride lots and weigh stations) that could be opened for parking at night. Several State partners have recommended that the Federal government facilitate this process by providing funds to conduct additional studies (e.g., field observations) where parking shortages are suspected. Furthermore, implementation guides can be developed to help standardize and increase the effectiveness of these studies, as can evaluation guides to help interpret the results of these studies for the purpose of formulating cost-effective plans for addressing the problem.

One of the most powerful features of the truck parking demand model is its ability to estimate future demand so that long-range plans can be formulated to accommodate this future demand. States could use this model to initially identify locations with possible parking shortages, then, based on local knowledge and field observations, refine the model to better reflect local conditions. The refined model could then be used to make long-term projections of parking demand so that appropriate long-term plans could be implemented.

6.2.5 How can inadequate parking at some locations be rectified?

When a parking shortage has been identified, a number of alternatives exist for how best to address that shortage. The alternatives that are best for a particular location will depend primarily on the local observations that were made while verifying the parking shortage. The following list describes some local observations that may be made and the possible solutions. The suggestions listed below are restatements of various suggestions made by the State partners consulted as part of the research for this report:

• Trucks are observed parking on the shoulder, but parking is available both at nearby public rest areas and commercial truck stops and travel plazas. This may be an indication that truck drivers are not aware of the parking that is available, and a program to disseminate parking information (e.g., with fixed highway signage, with VMSs, and through the Internet) might help. Truck drivers may not be aware of the safety risks of parking on the shoulder, and educational brochures could be used to teach them about these safety risks. Perhaps local enforcement of safe parking practices is lax. While waking a tired driver and forcing him to drive to another location is probably not a good practice for enforcement officers, leaving a warning ticket that explains the penalty for parking illegally and informs the driver of nearby parking locations might be more appropriate.
• Trucks are observed parking at overcrowded rest areas, but parking is available at nearby commercial truck stops and travel plazas. Truck drivers might not be aware of the available parking, and some of the suggestions mentioned above might help (e.g., VMSs, educational brochures). Truck drivers may favor the convenience of parking at a public rest area. If the exit ramps or roadways leading to nearby commercial truck stops and travel plazas are difficult to navigate, the State could choose to improve the exit ramps and improve access to the parking provided at the commercial facilities. Providing signage on corridors to inform drivers of the nearby facilities, and better yet, whether parking is currently available at those facilities, might also make use of the commercial facilities more appealing. If sufficient parking is available, the State can also make inappropriate parking less convenient by issuing tickets and levying fines.
• Overcrowded truck parking facilities are observed near a major city. Truck drivers may be using the parking facilities as a staging area to ensure timely arrival at a loading/unloading facility. Perhaps the owners or managers of the loading/unloading facilities could be convinced to provide access to a staging area for trucks making deliveries.
• Trucks are observed parking illegally, but legal parking is available nearby, information is available to guide truck drivers to the available parking, and access to this parking is convenient. In this case, truck drivers are likely parking illegally for the convenience of easy access to the highway, and enforcement activities could be used to make this illegal parking a less attractive option. Before beginning to enforce regulations more strictly, a warning period may be appropriate to give truck drivers a chance to become better acquainted with nearby parking facilities and the new enforcement practices.
• Other nearby parking facilities are near or at capacity, but parking is available at a public rest area. In this case, it is likely that the physical layout of the rest area makes parking inconvenient for truck drivers. For example, a rest area may provide only parallel parking for commercial vehicles. The solution may be to reconfigure the rest area to better accommodate parking for commercial vehicles in accordance with published guidelines (i.e., American Association of State Highway and Transportation Officials) for designing safer and more trucker-friendly public rest areas.
• All nearby parking facilities are near or at capacity. This situation is indicative of a true shortage of parking spaces, and a new source of parking must be located. However, correcting this problem does not necessarily entail construction of new public parking facilities. If other public facilities that are typically closed at night are available, parking at those facilities could be used to supplement the existing parking. A similar arrangement might be made with nearby commercial facilities, or the government could rent parking space from commercial facilities for nighttime use. Commercial truck stops or travel plazas may already have expansion plans that will meet the need, and local government can take steps to help facilitate those plans. Several State partner groups have suggested that the Federal government create a program to supply low-interest loans to develop new parking spaces at commercial facilities located where a demonstrated parking shortage exists. The State or local government may choose to expand existing public rest areas or construct new ones to meet the parking shortage.

6.3 Suggested Future Research

6.3.1 Distribution of Parking Supply

This report has presented a discussion of the model’s limitations and how the limitations hinder the ability of the model to accurately estimate demand at the segment level. While the demand model used in this study provides reasonable estimates of truck parking demand, improvements could be made to the model in the future to improve its ability to estimate parking at a more microscopic level. One specific limitation is that the model estimates demand for highway segments, ignoring variations in the parking supply that affect where drivers can park. Thus, there is currently a factor missing from the model that represents the geographic distribution of supply. Therefore, when field counts are compared to model estimates, as was done during calibration, it is not surprising that, in some cases, the estimates for one segment are too low, while the estimates for the next segment are too high. Additional research into how to add a factor to the model that represents the distribution of parking supply would make the model more accurate at the segment level and more useful for local planning purposes.

6.3.2 Commodity Flow Patterns

The model estimates parking demand as a result of truck drivers’ needs to rest and obtain services. It does not consider other factors that might influence demand in a particular region, such as typical commodity flows or the desire to “stage” close to a shipper/receiver for more quick and easy access. In contrast, the model distributes demand evenly across the network without consideration of these types of factors. Research into commodity flow patterns (particularly where flows are heavy) and the location of large distribution centers, ports, etc., could provide insight into “loading” factors that could be used in the model to help distribute the demand in a more realistic fashion. Additional research into commodity flow patterns is especially important because just-in-time delivery is becoming the standard for the movement of goods and products in the United States.

6.3.3 Short-Haul to Long-Haul Ratios

The report discussed the short-haul to long-haul ratio, factors that might affect its variability, and how the variability was modeled (by classifying each highway segment as either rural or urban and using a different value for the ratio for rural and urban segments). This methodology, however, may not capture the true variation in this parameter, and a more realistic model for estimating this ratio for each highway segment would likely result in better demand estimates. Therefore, it is recommended that future research be performed to understand how, when, and where the short-haul to long-haul ratio varies and what factors affect its variance. This could be accomplished by conducting origin-destination studies at a variety of geographic locations and at different times of the day.

6.3.4 Model Validation

As discussed in the report, the model was calibrated using data collected along nine corridors in four regions. The demand estimates from the calibrated model were examined for face validity by analysts and State partnerships; however, no formal validation process was performed. It is recommended that more field observational studies be conducted and that the results of these studies be used for model validation.

6.3.5 Public-Private Partnerships

A number of States recommended the development of public-private partnerships to assist with the development and financing of additional parking spaces. However, public-private partnerships often represent new ground for States, as these partnerships may involve pooling funding, sharing risk, and accommodating the need for the private sector to show profit on investments. These types of funding and risk-sharing arrangements often are at variance with more conventional State procurement practices and can be difficult for States to implement. Candidate issues associated with the creation of public-private partnerships for providing additional truck parking spaces include the following:

• Differences between the public and private sectors’ perception of what is important—the private sector’s foremost goal is to make a profit. The public sector is concerned with improved operation of the transportation system.
• Legal issues such as the following: Does the public sector agency have the legal authority to undertake a public-private partnership? Do Federal and State tax laws prohibit a public agency from receiving compensation from participation in a public-private partnership?

The study team believes that moving this particular recommendation forward will require additional research that documents how a successful public-private partnership that implemented a similar type of project succeeded. [d] This research would include such issues as the following:

• Documenting how the partnership identified and addressed issues.
• Identifying statutory and regulatory issues that need to be addressed (i.e., revenue sharing and procurement) prior to the partnership being able to implement the project.
• Observing how the partnership blended public- and private-sector goals (i.e., profit motive versus providing needed services).

The expected outcome of this research would be a case-study document that States would be able to use as a reference document to guide the development of other public-private partnerships.

6.3.6 Providing Information on the Availability of Parking Spaces

A common complaint heard throughout the course of the study was that drivers have a difficult time obtaining information on the location and whereabouts of facilities with available parking. This complaint was mirrored by similar complaints from commercial truck stop and travel plaza operators that they often have available spaces while drivers are parking on exit ramps and road shoulders. In the driver interviews, drivers indicated that they prefer not to park in overcrowded lots where driving can be difficult. A number of States recommended that providing information to drivers on the location of available parking facilities would help address these issues and help drivers find a place to obtain adequate rest.

Many States are studying how this type of information can be made available to drivers. Maryland, for example, received a grant from the I-95 Corridor Coalition to study the feasibility of using VMSs to provide information to truckers on the location of available truck parking.

Additional research in this area might include the following:

• Identifying which States are providing this type of information and how this information is being provided. This would include identifying what type of delivery system is being used by the State(s); the costs; the process used for obtaining, posting, and updating information; and who is responsible for system operation.
• Identifying any legal or regulatory issues that would need to be addressed in providing this information. For example, does posting information about the availability of parking spaces at commercial truck stops and travel plazas constitute advertising on behalf of that facility? Does a State have to provide equal access to all commercial facilities?

The expected product of this research would be a “lessons learned” report documenting issues that States would need to consider in developing and implementing such a service.

[a] The NTSB identified 19 States that have laws limiting the amount of time that a vehicle can park at a public rest area, 16 of which were also identified in this study. Three of the States identified by the NTSB did not provide complete information to this study team on whether there were time limits for some rest areas within the State.

[b]The truck parking supply inventory described in section 3.0 estimated both a minimum and a maximum supply for each highway segment. For the purpose of determining the demand/supply ratio, the maximum value was used. This approach helped ensure that the demand/supply ratio provided a conservative estimate of the locations at which inadequate truck parking exists.

[c] The 18 States cited refers to those States that identified this strategy in their draft action plans. It does not necessarily reflect the total number of States in which individual truck stop operators plan to expand facilities.

[d]An excellent summary of the types of issues encountered in developing public-private partnerships and recommendations on how to address these is presented in the ITS America/DOT-sponsored study Choosing the Route to Traveler Information Systems: Decisions for Creating Public/Private Business Plans. Although this report focuses primarily on Advanced Traveler Information Systems (ATIS), many of the issues will be similar to creating public-private partnerships for providing additional truck parking spaces.

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