Pressures on the Street

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Streets in the city are subject to enormous stress. The city's lifelines run directly underneath — subways; water and gas mains; power, phone and cable TV lines; and, in Manhattan, steam pipes. Since little of New York City is served by rail freight, very heavy trucks roll right into Manhattan. Traffic pounds the surface while escaped steam and rumbling subways create pressure and vibration from beneath.

OPENING THE PAVEMENT

For a time in the late 1980s, cyclists benefitted from stepped-up repaving and pothole repair. However, street-surface conditions generally are as hazardous and unpleasant as ever. Sixth Avenue, midtown's most central and heavily used uptown route, with midday bike traffic close to 200 bicycles per hour, has been nearly impassable since mid-1990. [1] Although Madison and Eighth Avenues have finally been repaired after years of almost unrideable conditions, other city streets have suffered a veritable epidemic of huge, long-lasting holes — probably the result of recent municipal belt-tightening.

Problem: Many surface problems come from the constant surgery performed on streets by utility companies. Before pavement is ripped up for utility work, it is sawed to make a two-inch-wide cut. When made parallel with the street or avenue, the two-inch cuts are wide enough to catch bike wheels. Workers often fill the cuts with dirt, but the fill generally sinks to a level 1-2 inches below the road surface. Filled or not, the grooves are a hazard, particularly when heavy traffic leaves no room for cyclists to maneuver around them; even if the groove doesn't actually grab a wheel, it can prevent the constant steering adjustments cyclists need to make to maintain balance.

Solution: There are two ways to alleviate this problem: cuts wider than a sawblade can be separated from the flow of traffic with barriers, or the cuts can be filled with two inches of asphalt. More generally, appropriate road pricing policies and provision of rail freight will help preserve smooth surfaces by reducing the constant pounding from heavy trucks.

Temporary steel plates, a permanent feature on many streets and a constant hazard to cyclists. Photo: Nick Plaitakis.

TEMPORARY COVERS

Problem: Steel plates or less-common wooden planks covering in-progress utility work are a constant feature of New York's street surfaces. Yet regulations governing their placement go largely unenforced. Wooden beams invariably have gaps between them, since the asphalt used to fill them is driven through the cracks after a few days. Steel plates also often have narrow gaps that can tip bicyclists or even grab a wheel. Even well-placed plates may shift position under the constant pummeling of heavy trucks and buses, opening dangerous gaps.

The steel plates themselves are an extraordinary hazard. About an an inch thick, the plates have sharp, squared edges that rarely lie flat against the street. As a result, cyclists often have to negotiate what amounts to a small, slippery curb — a tricky feat, especially for novice riders. The sharp edge can damage rims, puncture tires, jar the cyclist's wrists or even throw the cyclist from the bike. Asphalt can be feathered around the edges to create a more gradual incline, but this is not always done sufficiently on all sides — when it is done at all. The steel plates are also extremely slippery when wet; although the city DoT Traffic Rules and Regulations specify that plates must have a non-skid steel surface, this statute has never been enforced.

Solution: Careful placement of plates, and frequent covering with asphalt, should be made mandatory. Moreover, the city and its contractors should buy only plates with beveled edges; these not only afford a smoother ride, but are also less subject to movement on the street. [2] According to one supplier of steel plates, [3] plates can be easily and inexpensively cut with a beveled edge; as an alternative, the DoT or other major street surgeons such as Con Edison can create the bevel themselves with a blowtorch. A durable asphalt border should be required around unbeveled plates.

All plates should have a caustic surface to reduce skidding. Quickway and other companies have devised workable coating methods, consisting of layers of epoxy and sand, that can last for several years. The DoT in fact uses such a coating on the metal surfaces on the newly rebuilt Williamsburg Bridge bike-pedestrian path, as does the Transit Authority on station platforms. Fiberglass plates with a non-skid surface are another option. But because fiberglass is less rigid than steel, these plates are available only in sizes up to about four feet by six feet, or half the surface area of many steel plates now in use, and must also be tacked down. Still, several plates could be used along a lengthwise cut, and they would be easier for contractors to install.

PROTECTING AGAINST STEAM DAMAGE

Problem: Much good work done on Manhattan street surfaces is undermined by heat from Con Edison's underground steam pipes, arising primarily from leaks. The heat can raise the asphalt's temperature to the melting point, leading to waves and virtual dunes on the street surface. These waves appear most often around valves and manhole covers. This continual warping of the pavement forces the city to repair the same stretches of pavement again and again. Some patches last as little as four months. Many of the valves and covers are surrounded by one-square-foot heat-resistant concrete pads. Unfortunately, despite oversight by DoT and Con Ed, contractors do not always install pads large enough to stop warping of the asphalt near the edges.

Solution: City regulations require utility companies to maintain the pavement 12 inches around manhole covers. To avoid both warping and constant repairs, the radius should be expanded to three feet. Where streets are warped by submerged steam pipes in areas not near manholes or valves, Con Ed should be required to resurface the area with concrete. Similarly, bus lanes should be surrounded by a concrete border, to prevent the weight of the bus from causing the asphalt to “migrate” into dunes or waves.

CATCH-BASIN COVERS

Problem: Another trap for bicycle wheels is parallel-bar sewer grates. Many have openings just wide enough to catch and ruin a rim and throw a cyclist from the bike. Cyclists who swerve into traffic to avoid the grates risk collisions with motor vehicles.

Bicycle-safe sewer-grate covers. Simple solutions exist for most street hazards.

Solution: A federal law banning the parallel grates has been in effect for a decade, and many municipalities have made the switch to safer designs. Even New York State has its own standard for bike-safe grates, which are met by bike-safe grates manufactured by several companies.

Nevertheless, the city's Department of Environmental Protection (DEP), which has jurisdiction over the gratings, has languished, claiming that bike-safe grates lack other important water-draining qualities. Until several years ago, DEP still occasionally installed unsafe grates, or else installed safe grates backwards. [4] Moreover, the city still has thousands of old unsafe grates, presenting a serious hazard to bicyclists. Despite a policy change stating that all procured and replaced grates will be bike-safe, which was affirmed personally by DEP Commissioner Appleton to the Bicycle Advisory Committee in 1990, no systematic replacement program appears to be in place.

NOTES:

1. In 5 hours of traffic counts on 6th Avenue between 34th and 48th Streets in 1988-90, Trans-portation Alternatives recorded 933 bicycles, an average of 187 per hour. In 1992, however, the rate fell to 114/hour, no doubt reflecting the avenue's appalling surface conditions as well as the removal of the bicycle lane. See Appendix 2.
2. Telecom with Ellen Fletcher, Palo Alto cycling activist and former City Council member, March 1992.
3. Telecom with Alan Pavlick, Quickway Iron Co., Sullivan County, NY, 914-794-1900, March 1992.
4. One grate design has very narrow (bike-wheel safe) slots on the side furthest from the curb, but wider ones next to the curb to facilitate drainage. These are often installed backwards in New York, with the wider slots away from the curb.

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a) A Bumpy Ride
 Pressures on the Street
c) Chapter 6 Recommendations