Traffic congestion

“ When the congestion becomes so great that it threatens to hold up the unending stream of motor-lorries which rolls through the city, day and night, between the great cantonments in the outskirts and the port, a tall British military policeman suddenly appears from nowhere, shoulders the Greek gendarme aside, and with a few curt orders untangles the snarl into which the traffic has gotten itself and sets it going again. ”

“ It recognized that extension of the freeway system into urban areas had relieved traffic congestion on many arterials but, by the location and design of interchanges, had imposed heavier volumes on other arterials or city streets on which cities were not prepared to finance improvements. Congress also recognized that generally the traffic operations systems in urban areas were not receiving the full advantage of modern traffic engineering techniques, due primarily to lack of funds. ”

“ In consequence there is often on such relatively short sections of highway an actual development of congestion or an approach to it.
If we inquire into the reason for the failure to augment the traffic facility in proportion to the increase in traffic we usually encounter right-of-way difficulties. At the approach to the city road-bordering developments thicken to such an extent that the additional space required for the widening or other increase of the highway facility may be obtainable only at heavy cost because of the closely crowding suburban residences and industrial establishments. ”

“ The Public Roads Administration’s studies of the traffic-discharge capacity of highways have reached the conclusion that a one-way, two-lane roadway with no intersections will discharge without unreasonable congestion an hourly traffic of 3,000 vehicles moving at an average speed of 35 miles per hour. With equal congestion but with three traffic lights per mile, each set on a half-minute interval, the hourly discharge is reduced to at best 1,500 vehicles an hour. One or two more traffic lanes would have to be provided to restore the highway to its intersection-free capacity. ”

“ In very congested districts motor trucks are at a great disadvantage because they cannot be used at their most efficient speed. If the congestion can be eliminated or at least relieved by such means as one-way traffic, paving parallel streets, removing buildings which obstruct passage, widening driveways, elevating railroads and street cars, supplying overhead crossings, making subways, or by careful rearrangement and planning of terminal facilities, warehouses, and other accommodations, the cost of transportation in the large cities may be materially reduced. ”

“ Any attempt to discharge the free-flowing express traffic at one point into the surface streets of the downtown section, through such streets to find its way to distributed parking places, is likely to create an exit confusion and delay that will cause at the end of the express route a loss of much of the time saved by the free movement en route. Such an attempt, moreover, may cause a degree of congestion in the surface streets near the express highway terminus greater than that resulting from the present distributed approach of vehicles. ”

“ We were on a bus whose "route" terminated some five miles from home, which we proposed to reach by a tram, and, the hour being late, it was our chances of catching a car that were worrying Mary.
"Never get flurried," I went on. "If people would only go ahead calmly and steadily.... What causes half our traffic congestion? Flurry. What makes it so difficult to move quickly in the streets? Flurry. What is it clogs the wheels of progress everywhere?" ”

“ When one observes the countless impediments that embarrass the movement of twentieth-century traffic through the eighteenth century streets of some eastern cities one wonders how long it will be, with the assured further increase in traffic, before complete congestion will result. ”

“ On such roads a slight restriction of absolute freedom of movement is to be expected during the few short periods of maximum hourly traffic volume that occur in the course of a year. So long as such occasional restrictions do not result in the creation of a dangerous condition or in substantial congestion or retardation of the traffic they may be accepted as reasonable. On this basis, an average daily volume of 2,000 vehicles may be considered as within the reasonably convenient discharge capacity of a two-lane highway. ”

“ In establishing one-way streets attempts are usually made to avoid left-hand turns whenever possible. The figures on pp. 424 and 426 show sketch plans for rotary service. When there are street-car tracks or other local obstructions slight changes may have to be made. Note only two full passing places for vehicles, A, and as only a part of the traffic will want to cross congestion and danger are largely eliminated. There may be one, two, or more lines of traffic at B; depending on the width of the street. ”

“ As the traffic volume increases the opportunity for passing diminishes, lines of vehicles form and, accordingly, the difference in speed between successive vehicles becomes less, even though the average speed of all vehicles may not be affected greatly. Plate 26 shows that such difference in speeds is a much more sensitive index of congestion than is the average speed of all vehicles. ”

“ When the traffic volume on a two-lane road does not exceed 300 vehicles per hour the congestion on grades resulting from slow-moving vehicles in numbers normally found on main highways is not sufficient to justify the construction of a third lane, regardless of the alinement and profile, for grades up to 7 percent. ”

“ The big percent is one way traffic. To get a block or so away from where you are you execute some geometric figures they didn't have in the books when I took geometry.
This day we had an accident. Driving in the downtown congestion a car from the lane to our right pulled into us, tearing off the right hind fender of our almost brand new convertible. Traffic stopped momentarily only. You would think the two owners were exchanging pleasantries. They gathered up the pieces and pulled out what was left of the fender to keep the tires from scraping, and away we went. ”

“ The congestion of traffic in the downtown streets of our large cities is due to four causes: (a) the increased number of vehicles, (b) the different rates of speed at which different types of vehicles desire to move (horse-drawn vehicles, street cars, motor trucks, trucks, motor cars, motorcycles, etc.) , (c) the inadequate width and faulty arrangement of streets due to the lack of planning, and (d) the improper driving and parking of vehicles.
The older streets cannot now be widened except at very great expense because the private property which fronts on them is so valuable. ”

“ If further, we consider the case of the smallest urban communities—the highway or ribbon towns that at intervals stretch out along main highways and vary from a block or two to several blocks in width—the bypassing of such places is not only helpful to the preponderant through traffic, but is usually necessary for the avoidance of congestion and serious accidents and the protection of life on the main street of the little community. ”

“ Relatively little serious damage was done, but the fact that traffic had often to be or worked under difficulties, the reduced lighting generally maintained throughout the more vulnerable parts of the country, and the congestion which followed each cessation of traffic constituted serious hindrances to railway working. ”

“ With considerable traffic it may be necessary to divide up the work, giving one set of observers the in-traffic and another the out-traffic, one man to observe passenger automobiles another trucks and delivery wagons, or one man to jack up and weigh front wheels and another rear. System will result in more accurate results, and in less loss of time for the drivers, and less congestion of traffic. ”

“ It is unwise to recommend for general use a capacity limit for four-lane highways in terms of total traffic since it is felt that local conditions producing traffic volumes sufficient to justify more than four lanes will be so individual in their characteristics that each case will require special study. Serious congestion on four-lane pavements would occur only in proximity to large cities, where in the periods of heavy volume, the traffic is not evenly divided between the two directions. ”

“ With the increase in traffic and liability to urban congestion there is some justification for keeping spaces in front of ambulance stations, hospitals and fire stations clear of parked vehicles so that ambulances and fire appliances can move in and out; also in front of schools so that children can be clearly seen from passing vehicles. ”

“ This conveys the message 'priority to be given to vehicles coming from the opposite direction'. At the other end of the single lane section, the informatory sign at figure 132 should invariably be used (see paragraph 198) .
(c) Waiting restriction and limited parking signs (Regs. 316 to 324) 83. With the rising volume of road traffic it becomes increasingly necessary to combat urban congestion, and also to prevent stopping on fast through routes in rural areas, by placing legal prohibitions or restrictions upon the occupation of streets and roads by standing vehicles. ”

“ The questions are nation-wide. Twenty-odd states and forty million inhabitants of the interior are actually suffering from the congestion; fifteen states and thirty million people on the Atlantic coast are complaining under imposts of burdensome traffic; the western states with their seven millions, which would triple in ten years were the burden removed, find their growth paralyzed by the same cause. ”

“ We believe that an effective step which could be taken to reduce these casualties would be to ensure that at the great majority of junctions, and certainly at those junctions where serious danger exists, the minor road is distinguished from the major so that drivers on the minor road are given a clear indication that they should give way to major road traffic. ”

“ There is ample support for a legislative determination that the peculiar character of this traffic involves a special type of use of the highways, with enhanced wear and tear on the roads and augmented hazards to other traffic, which imposes on the state a heavier financial burden for highway maintenance and policing than do other types of motor car traffic. ”

“ Where a motor vehicle carries an indivisable oversize or overload cargo, to the detriment of traffic safety, it shall be driven at a time, along the route and at the speed designated by the traffic control department of the public security organ and hung with conspicuous signs. ”

“ And with all the finesse of their work the traffic moves like molasses. Long double and triple files of touring cars and limousines, the combined cost of which would render statistics such as would gladden the heart of a Sunday editor, make their way up and down the great street tediously. If a man is in a hurry he has no business even to essay the Avenue. And occasionally the whole tangle is double-tangled. The shriek of a fire-engine up a side street or the clang of an ambulance demanding a clear right-of-way makes the traffic question no easier. ”

“ In this country where the road pattern is so complicated, we think it would assist travellers in finding their way between important towns if a system of Primary routes other than motorways was established, the roads in which would be clearly distinguished by having directional signs of a particular colour. Moreover, we foresee that this distinction might eventually enable a code of improved driver conduct, aimed at improving traffic flow and safety, to be applied generally to these Primary routes. ”

“ The problem can occur even when there is more than one lane. At times of light traffic flow, a vehicle being driven in the left hand lane at 70 mph might close unexpectedly rapidly on a slow-moving lorry, or on a queue of vehicles waiting to pass it. ”

“ Trucks, delivery wagons, ice-wagons, etc., frequently stop back of the line of parked automobiles in the street restricting the way and causing all passing vehicles to go over to the wrong side of the street thus congesting traffic and furnishing a source of danger. ”

“ A special problem arises here since traffic will arrive at the terminal junction (usually in the form of a roundabout) without leaving the main carriageway of the motorway. It is therefore imperative that adequate warning should be given so that drivers, though still on the motorway, will reduce speed to the greater extent which is necessary to enable them to negotiate the junction in safety. ”

“ Where separation of grades at highway intersections is not feasible, and at all points where vehicles may be expected to cross, enter, or leave the interregional highway, the design shall be such as to insure a high degree of safety in crossing, entering or leaving it, without installation of traffic control signals, which shall in no case be employed. ”

“ But the common impression that provision of such routes would constitute invariably a complete, or even a substantially adequate, solution of the highway problem at cities is not well-founded. It is a fallacious conception of the need for adequate accommodation of the traffic moving over the rural highways. From the standpoint of the cities it fails as a solution of the most serious aspects of the problem. ”