1957: First traffic lights in Offenbach

When the dignitaries from the town hall and the telecommunications department of the municipal utilities posed for a photo in front of a gray switch box on March 1, 1957, at 11 a.m. on the dot, they surely suspected that as traffic density increased, even more traffic lights would soon displace the - then still municipal - police officers from their pedestals. In 1957, however, probably none of those present could have imagined that the city would have to set up two and a half new systems every twelve months on average over the next half century. But in 2006, 55,578 cars were registered in Offenbach alone. Their drivers and the many guests want to move along 212 kilometers of road between the Main and the city forest without traffic jams.

However, it was already rumored at that celebration that the flashing lights could become a hotly debated topic at Offenbach's regulars' tables. City councillor Albert Gasch, who switched on the bulbs of the first traffic lights at the push of a button, is quoted in the Offenbach Post of March 2, 1957 as saying: "I hope that it will be a traffic control system and not a traffic obstruction system (..) to serve the welfare of the citizens".

The right interpretation of "welfare" is still being debated today at almost every citizens' meeting. Speed limits, signal-controlled crosswalks and draconian penalties for offenders are demanded for the safety of their own neighborhoods. At the same time, traffic lights and surveillance three blocks away are discredited as an obstacle and a rip-off trap. An ambivalence that the city fathers and mothers have been living with for five decades. During this time, however, those responsible have invested a lot of money in making traffic flow smoothly through Offenbach. Keyword "green wave".

Klaus Dallmann and his team at the Office for Urban Planning and Construction Management are working on intelligent solutions. Today, traffic requires sophisticated formwork technology in order to intervene flexibly in the flow of traffic. Before any decision is made on the purchase of systems costing between fifty and one hundred thousand euros, a calculation is first made. How many cars drive through the junction? What is the capacity of the roads there or what is the situation at the neighboring junctions? The employees are expected to look into the future. The traffic that new high-rise buildings are expected to attract must be taken into account at Kaiserlei, as must the future development of the Main district.

Two programs in particular are currently being worked on: Possible developments in Bürgel are being simulated following the construction of the new Mainzer Ring and around the main railway station, where there are plans to open up Kaiserstrasse in two directions. The new traffic relationships must be fitted into the existing "green waves". Some conflicting goals arise because "free movement" for one citizen means a longer red phase for another: three corners further on. The optimization skills of the planners are constantly in demand.

Four different signal programs are coordinated for each system to cope with different loads, depending on the time of day. The traffic lights are connected to a computer that reacts depending on the traffic. Detection loops on the main roads automatically control the length of the green and red phases as well as the special switching for the buses.

Fifty years ago, traffic lights still lacked chips and binary logic. Drivers triggered the impulse themselves. Kaiserstraße, once an Offenbach hub for buses and (streetcar) trains, was switched to "green" unless a tire put a load on an induction loop in Bernardstraße. What seems to be the ideal solution in retrospect didn't really work in the good old days. Before the final expansion of Berliner Strasse, traffic from Frankfurt used to flow through Nordend. According to the chroniclers of the local newspaper, the traffic lights in Kaiserstrasse rarely showed "green" for more than thirty seconds.

Today, 59 signal systems, or 43 percent, are operated around the clock. The others are switched off at night, usually between 10 pm and 6 am. 38 traffic lights are used exclusively to protect pedestrians. At the push of a button, they extend the green phase for pedestrians from six to 25 to 65 seconds.

86 times at Offenbach junctions, buses are given priority. If it sends a signal to the control unit, its green time is extended or swapped. 29 traffic lights are equipped for the blind and visually impaired, mostly with a vibration sensor whose plates indicate the direction of travel. At seven installations, the green time is announced via loudspeakers. A total of 75 crossings have been secured in consultation with the associations for the blind. These are added to each year when roads are rebuilt or reconstructed, as is currently the case in Kaiserstrasse.

There is a so-called "green arrow" at ten signals, which allows right turns on red. After the vacations, there will only be nine left because drivers at the Karl-Herdt-Weg junction have too often violated the rule of giving priority to pedestrians when the light is green. Two recent accidents were the result.

The city has now entrusted the specialists at Energieversorgung Offenbach AG (EVO) with maintenance, including checking all control and safety elements and operating the 2,347 signal heads. EVO ensures that the 5,789 screwed-in bulbs, which burn for around a year, work day and night. 56 percent of the systems are equipped with energy-saving 10-volt technology.
This reduces energy costs by 40 percent. New systems, such as those in the Klinikum parking garage, are equipped only with light-emitting diodes (LED technology). This reduces consumption by around eighty percent compared to conventional 230-volt technology. However, the LED signaling devices are around three and a half times more expensive to purchase than conventional light sources, and some older systems cannot be converted for the new technology. In 2006, the 138 traffic lights in the leather city consumed a total of 794,722 kilowatt hours of electricity, as much as 300 average households. In 1996, 127 systems still consumed 867,594 kilowatt hours. The use of resource-saving lamps pays off.

Around one million euros are spent annually in Offenbach's budget under the "traffic lights" item for planning, installation, electricity consumption and maintenance. The claim, repeatedly discussed in the media, that the red light offenders who are flashed help the city's budget is false. Unfortunately. The fines from the three cameras at the four locations go to the regional president in Kassel, i.e. to the state. The cities, which operate the speed cameras, only receive a processing fee of 15.34 euros per case and photo. In Offenbach, 1,276 offenses were recorded in 2006. In the first half of 2007, there were 754. Measured against the cost of the checks, but above all for the maintenance of the traffic lights, the sum transferred is not really a good deal. And yet: monitoring is important. The revenue from violations can be quantified, but the number of people who are still alive today because the "speed cameras" deterred drivers from speeding through traffic lights on red will remain unknown forever.

The junction of Bernardstraße and Kaiserstraße, once described by the Offenbach Post as one of the most dangerous crossroads, is now only moderately busy at best. You can't tell from the poles that flash there today that a piece of local history once began here, as the city has so far skimped on a small commemorative plaque.

Last but not least, some general information from Wikipedia on the subject of traffic lights:

"The world's first traffic light was installed in London in front of the House of Parliament in 1868. It was operated with gas light and exploded after a short time. It was only after the invention of electric light that traffic lights were installed again to regulate traffic from 1912 onwards. The traffic lights installed in Cleveland, USA, on August 5, 1914, are considered to be the first traffic lights in the world and had only two lights: one red and one green. Its creator Garrett Augustus Morgan is therefore regarded as the inventor of the traffic light. The first three-color traffic lights were installed in Detroit and New York in 1920.
In Europe, the first three-color traffic lights were not installed until 1922 in Paris (Rue de Rivoli / Boulevard de Sébastopol) and Hamburg (Stephansplatz) [3]. In the 1920s, traffic lights first became established in large cities: The first traffic light in Berlin was at Potsdamer Platz in 1924, in Milan (Piazza Duomo) and Rome (Via del Tritone / Via Due Macelli) in 1925, in London (Piccadilly Circus) and Vienna (Opernkreuzung) in 1926, in Munich (Bahnhofsplatz) and Prague (Hybernská / Dláždìná / Havlíèkova) in 1927 [4], in Bremen (Brill), Essen (Alfredstr. / Bismarckstr.) and Nuremberg (Königstor) in 1928, Barcelona in 1929, Frankfurt am Main (Kaiserstraße / Neue Mainzer Straße), Leningrad, Moscow [5] and Tokyo [6] in 1930 and Hanover (Kröpcke) in 1931 [7].
Smaller cities such as Braunschweig [8] (1951), Basel [9], Helsinki [10] and Lucerne [11] (1952), Gelsenkirchen (1953), Heilbronn (1954) and Bremerhaven (1957) did not receive their first traffic light systems until the 1950s.
The first pedestrian traffic lights were introduced in East Berlin on October 13, 1961". (sl)