Understanding the Difference/ Speed Bumps vs. Speed Humps

Understanding the Difference/ Speed Bumps vs. Speed Humps

In urban planning and road safety, it’s crucial to understand the tools used to manage vehicle speeds and enhance pedestrian safety. Speed bumps and speed humps, though often confused, serve distinctive functions in traffic calming. This article explores the differences between these two measures, their design variations, and their role within broader traffic calming strategies. We’ll also delve into community perspectives and the legalities surrounding their implementation, providing a comprehensive look at how these devices shape our driving experiences.

Defining Speed Bumps and Speed Humps

Physical Characteristics

Speed bumps and speed humps are both traffic calming devices designed to reduce vehicle speeds, but they differ significantly in their physical characteristics. Speed bumps are typically shorter in length and have a more abrupt profile, leading to a more pronounced slowing effect on vehicles. They are often between 3 to 6 inches in height and 1 to 3 feet in length. Speed humps, on the other hand, are designed to be longer and more gradual. They usually extend across the full width of the road and have a height of 3 to 4 inches, with a length of 10 to 14 feet. This design allows for a gentler deceleration and acceleration, making them less disruptive for drivers and passengers. Here is a comparison of their typical dimensions:
Device Type Height (inches) Length (feet)
Speed Bump 3 to 6 1 to 3
Speed Hump 3 to 4 10 to 14

Common Locations and Purposes

Speed bumps and speed humps are traffic calming devices strategically placed to slow down vehicles in various settings. Speed bumps are commonly found in parking lots, where the goal is to control the pace of slow-moving vehicles. They are effective in areas where pedestrian safety is paramount and vehicle speeds need to be kept to a minimum. On the other hand, speed humps are typically installed on residential streets and around schools to reduce vehicular speed and enhance safety for residents and children. The purpose of these devices extends beyond just reducing speed; they also serve as visual and physical reminders for drivers to maintain caution in areas prone to high pedestrian activity. The installation of speed bumps and humps is often a response to community concerns about speeding and traffic safety.

Impact on Vehicles and Drivers

The introduction of speed bumps and humps has a significant impact on the behavior of drivers and the performance of vehicles. Speed bumps, with their greater height, compel drivers to reduce speed more abruptly to avoid discomfort or vehicle damage. This can lead to a variety of responses from drivers, including swerving to avoid the bump or seeking channels that allow for a smoother passage. Such maneuvers, while intended to mitigate the impact, can result in unsafe driving practices, particularly when drivers swerve into oncoming traffic or adjacent lanes. Speed humps, being wider and lower, encourage a more gradual deceleration, which can be less disruptive to traffic flow. However, they may not be as effective with larger vehicles, such as SUVs and trucks, which can traverse these humps with minimal reduction in speed. This discrepancy in effectiveness raises questions about the optimal design for traffic calming measures that cater to a diverse range of vehicle types.

Design Variations and Their Implications

Traditional Speed Bumps

Traditional speed bumps are the narrower, more abrupt traffic calming devices that many drivers are familiar with. Their steep angle of approach and typically higher elevation make them particularly effective at reducing vehicle speeds. However, this design can be more jarring for drivers and passengers, and can cause discomfort or even damage to vehicles if traversed at higher speeds. While traditional speed bumps are effective for speed control, they are often criticized for their impact on emergency vehicles. The abrupt nature of these bumps can hinder the quick response of emergency services, leading to discussions about alternative designs that balance safety and efficiency.

Modern Speed Humps

Modern speed humps are engineered to slow down traffic effectively while minimizing discomfort for drivers and passengers. Unlike their predecessors, these humps are designed with a gentler slope and a wider span across the road, which allows for a smoother transition at lower speeds. The design aims to reduce vehicle speeds without causing excessive deceleration or discomfort. Speed cushions, a variation of modern speed humps, are gaining popularity due to their ability to accommodate larger vehicles. These are wider than traditional speed humps and strategically placed to allow emergency vehicles and buses to pass with minimal interference. This design consideration ensures that critical services are not unduly delayed by traffic calming measures. While modern speed humps are effective for their intended purpose, they are not without criticism. Some road users express concerns over their impact on driving patterns, with reports of drivers attempting to navigate around them or maintain higher speeds, thereby reducing their effectiveness.

Alternative Designs: Swedish-Style Speed Tables and Raised Intersections

Swedish-style speed tables and raised intersections are innovative approaches to traffic calming that offer distinct advantages over traditional methods. Swedish-style speed tables are characterized by a single sharp ramp leading to a raised platform, which facilitates a smoother transition for larger vehicles, such as buses. This design contrasts with conventional speed tables that typically feature two sharp ramps. Raised intersections elevate the entire crossing to the level of the surrounding sidewalks, providing a continuous path for pedestrians and enhancing safety for all road users. These intersections have ramps at each entry point, signaling drivers to slow down as they approach. In urban areas, particularly around schools, these alternative designs are often coupled with additional safety measures such as zebra crossings to further protect pedestrians.

Traffic Calming Strategies Beyond Bumps and Humps

Entry Signage and Visual Cues

Entry signage and visual cues play a crucial role in alerting drivers to upcoming traffic calming measures, such as speed bumps and humps. Effective signage is not only a legal requirement but also a key factor in ensuring driver compliance and safety.
  • Entry signage typically includes speed limit signs and additional plaques indicating the presence of speed bumps or humps ahead.
  • Visual cues can range from road markings to colored pavements, which help to reinforce the message conveyed by the signage.

Diverters and Speed Cushions

While speed cushions are designed to slow down vehicles without impeding their passage, diverters are a more aggressive approach to traffic calming. Diverters, often placed at intersections, force vehicles to alter their route, effectively reducing cut-through traffic and enhancing safety for cyclists and pedestrians. Speed cushions, on the other hand, are a softer measure, allowing for the passage of larger vehicles like emergency services while still managing vehicle speeds. They are particularly favored in areas where access for such services must remain unobstructed. However, community feedback suggests a preference for diverters over speed cushions, citing the latter’s limited effectiveness in deterring cut-through traffic. The debate continues as to which method serves the community’s needs best, balancing safety, efficiency, and cost.

The Role of Speed Tables in Urban Planning

Speed tables are becoming an integral part of urban planning, especially in areas with high pedestrian activity such as school zones. Their design, featuring a flat top with ramps on either side, encourages vehicles to reduce speed to safer levels. This design is particularly effective around schools, where they are often combined with zebra crossings to facilitate safe pedestrian movement. Swedish-style speed tables offer a variation with a single sharp ramp, providing a smoother transition for larger vehicles like buses. Raised intersections, another form of speed tables, elevate an entire intersection to the level of the footpath, simplifying the crossing process for pedestrians and emphasizing their priority. The implementation of speed tables and their variations is a testament to the evolving nature of traffic calming measures, reflecting a shift towards more nuanced and context-specific solutions.

The Debate: Community Preferences and Concerns

Safety vs. Comfort: The Cyclist’s Dilemma

The introduction of speed bumps with cutouts has sparked a debate among cyclists. On one hand, these modifications aim to provide a smoother ride for those on two wheels, addressing the discomfort and potential damage caused by traditional speed bumps. On the other hand, some cyclists express concerns over safety, such as the risk of clipping a pedal on the cutout. A recent survey highlighted the community’s preference for these bicycle-friendly modifications. A significant majority of respondents favored the adapted speed bumps, indicating a positive reception among the cycling community. However, the effectiveness of these measures in terms of safety remains a topic of discussion, with some cyclists reporting near misses and concerns about potential crashes. In the context of urban planning, the integration of cyclist-friendly speed control devices must be carefully considered. It is not just about slowing down vehicles but also about ensuring that the measures do not impede the flow of bike traffic or introduce new risks.

Resident Feedback on Traffic Calming Measures

Community response to the implementation of speed calming measures often varies, with some residents expressing strong opinions on their effectiveness and impact. Mayor Johnson’s assertion that traffic calming efforts are working is backed by data, indicating a reduction in reckless driving. However, not all feedback is positive. Residents like Daniel Reimer voice concerns, suggesting that speed bumps, while common, should be a last resort due to their inconvenience for both drivers and cyclists. Alternative measures such as diverters and speed cushions are mentioned as having their own sets of advantages and disadvantages.The table below summarizes key points from resident feedback:
Concern Suggested Alternatives Perceived Impact
Inconvenience Diverters, Speed Cushions Mixed Opinions
Effectiveness Data-Driven Approaches Positive Reports
Preference Non-Bump Solutions Varied Preferences
Engaging with the community to understand these preferences is crucial for urban planners and policymakers when designing traffic management strategies.


In summary, while speed bumps and speed humps are both traffic calming measures, they serve distinct purposes and are suited for different environments. Speed bumps, with their higher elevation and shorter width, are more aggressive in slowing down vehicles and are often found in low-speed areas such as parking lots. Speed humps, on the other hand, are gentler and more elongated, making them suitable for residential streets and school zones where a smoother deceleration is preferred. Understanding the differences between these two can help in selecting the appropriate measure for a given area, ensuring both safety and comfort for all road users.