Safe Driveway Design

Driveways present an often overlooked potential for accidents. Traffic entering the road from a driveway faces the same conflicts as traffic at an intersection. Therefore, the design and location of a driveway can affect the safety of the road.

Because accident rates and congestion increase as the number of driveways goes up, more and more communities are turning to access management to maintain the safety and capacity of their roads. By requiring subdivision lots to share driveways, the number of entrances can be reduced. This improves the safety and traffic flow on the road.

Access management primarily applies to arterials and collectors because they carry a large amount of traffic. Land access is the main role of local roads, so it does not make sense to be overly restrictive.

Landowners should be required to obtain a highway work or building permit for construction within the right-of-way of a public road, including driveways. The permit review and inspection process can minimize the safety and operational effects on the road, and make sure it is built correctly with no damage to the roadway. It allows the municipality to make sure hazardous headwalls are not built within the right-of-way.

Poorly designed driveways should be brought up to current standards under these circumstances:

• The property is redeveloped

• The municipal planning board decrees a change of use

• The municipality should upgrade nonstandard driveways during construction projects

An existing nonstandard driveway can be ‘grandfathered’ unless the accident history shows it to be unsafe. Forcing alterations to existing driveways is a good way to become unpopular with the natives. Business owners tend to be especially sensitive to changes that they think may make it more difficult for customers or deliveries. Proper driveway design helps prevent this.

The frequency of accidents on a road has been shown to increase as more driveways are built. Minor commercial and residential lots should be limited to one driveway for this reason.

Driveways should be perpendicular to the street. Angled driveways cause difficulties for older drivers and others with restricted neck movement. Older drivers are becoming an increasing portion of the population. Acceptable angles range from 75 to 105 degrees.

Twelve feet in width is usually sufficient for residential driveways. Minor commercial driveways are normally 24 feet wide, but can range from 22 to 30 feet. The corner radius needs to be sufficient for the vehicles using the driveway.

Sight distance for driveways is similar to sight distance for intersections. Three types of sight distance are important in driveway design. The minimum allowable sight distance approaching the driveway should be stopping sight distance. This allows drivers approaching the driveway to see a vehicle exiting the driveway in time to stop and avoid a collision. Preferably, drivers turning out of a driveway or making a left turn into it should be able to see oncoming traffic from far enough away to make the turn safely.

Often a building lot will be in a location with less than desirable sight distance. In this case, the driveway should be placed at the location along the lot’s frontage with the best sight distance. This is a good requirement to have in the municipal building code. Planning boards should require that all parcels have safe driveway locations when property is subdivided.

The Importance of Barricade Safety Lights

You’re driving home late from work one night when you notice flashing lights. It’s not an ambulance or a police vehicle, but the small warning lights indicating that road work is being done in the area. You slow down and drive through the work zone without issue. While you might see these lights once in a blue moon, there is no denying the importance of them.

Barricades are an essential part of any road working project. They indicate the border of the zone and prevent traffic from causing interruptions. Reflective strips on these barricades can help at night or in overcast conditions, but they rely on the headlights of passing cars to shine on them. Safety lights shine independently and are visible from a greater distance. They can be attached to various barricades and placed on top of traffic cones to bolster the presence of a road work zone. Multiple lights can be used to indicate where traffic will divert when a lane must be closed.

The battery life of safety lights is a crucial factor in ensuring that barricades are effective. Incandescent lights are typically the less expensive option; LED safety lights last longer and use less power to give off the same amount of light. Solar is also available in providing a longer battery life through small solar panels that are attached to the lights.