History: The North Sea Flood 1953 and the response by the TNO Physics Laboratory staff


The 1953 North Sea Flood and the response by the staff of the TNO Physics Laboratory

Less than three weeks after the devastating flood that had stricken the Netherlands, Belgium and England on the night of January 31 to February 1, 1953, a report was compiled on the contributions by the staff of the Physics Laboratory TNO to the relief work. The report dates from February 19, 1953. This report is made up of the appreciation of the managers and individual reports by employees who provided support. The report is in the form of an introductory section and appendices. An anonymised story was distilled from this report with small text adjustments and removing duplications. Additional explanation or information is enclosed in square brackets.
The emergency response to the flood of 1 February 1953 by the Physics Laboratory consisted primarily of radio communication support. Five transceivers were used (including the Middelharnis – Hellevoetsluis radio link).

Sunday, February 1: The first personal actions

Radioamateur channel PAoB1

At 1 PM, an employee of the laboratory, being a member of the Association for Experimental Radio Research in the Netherlands (VERON) with call sign PAoB1, received an urgent call from the Hague department of the Red Cross asking him to report to the Feyenoord Stadium in Rotterdam. His account:

The ‘The Hague’ chapter of the Red Cross comprised an emergency telecommunications unit. I was appointed to be the leader of that unit during the week of the disaster. A year earlier, this unit had been established in close collaboration with the Special Radio Service of the P.T.T..  A telephone exchange with 6 lines was set up and connected in the Stadium. A radiotelephone car took care of the connection to the fixed Rotterdam telephone network. In addition, a radiotelephone connection with the Ahoy fair and event halls had to be set up. This assignment was completed on Monday morning at approximately 3 AM. The whole setup operated for 2 days, after which the ‘The Hague’ chapter of the Red Cross had to move on.

The telecommunications unit was ordered to move to the Unilever building to set up a radio station for the Regional Commissioner of the Red Cross Rotterdam. This radio station operated under call sign PA01OL at a frequency of 3700 kHz. The 3700 kHz frequency band was designated for amateur emergency network communications. A length of copper wire of about 30 m length was used as the transmission antenna. The antenna was connected via a Collins filter with the transmitter output amplifier. The power consumption of the transmitter was 50 watts and was modulated using a plate and screen grid of the transmission tube.
Fifteen minutes after arrival at the location, the first telegrams were transmitted to The Hague, where PA0YG and PA0YG2 worked for the Netherlands Government Information Service.

Soon, the operations needed their own telephone connection with the Rotterdam telephone district. Thanks to the excellent cooperation with the Unilever management, this was quickly arranged.

As the Vlaardingen river police had their own mobile radio network, their telegrams for and from The Hague were also sent via PAoNOL.

The Rotterdam location also had a direct V.H.F. connection through PYE transceivers with Den Bommel and Achthuizen in the disaster area.

The PA0FY transmitter, which was located on the Area Health Authority building in Rotterdam, had a telegraph connection with various ships on the frequency channel 3580 kHz. PA0FY relayed their messages to The Hague via the PA0NOL transmitter (Red Cross location Rotterdam).

The operations team of the Red Cross  PA01OL transceiver always consisted of 4 men, who were relieved every 24 hours. A rotation scheme was created. The importance of this Red Cross setup was evident during the evening and night periods. As the evening and night conditions on the 80 m band could not guarantee a direct connection between The Hague and the emergency areas, the Rotterdam transceiver location acted as a communications relay. The installations, which were built and made available by the amateurs for this location, operated throughout the whole week without failing for a  single moment. The installations fully met the expectations.

Assistance in creating the amateur emergency network (PA0YG)

On Sunday morning, Sjors (George) de Bruin, an employee of the laboratory and a VERON radio amateur with call sign PA0YG, discovered that there was a major disaster going on while listening to the Scheveningen Radio transmissions. The Special Radio Service of the PTT (BRD) meanwhile had contacted the Hague radio amateur Bob van Binnendijk (call name PAoGVB, later temporarily PA0YG2). He possessed a strong radio transceiver station. He established contacts with radio amateurs in the disaster area. Sjors was asked for assistance with his more powerful 120-125 W transmitter. These two radio amateurs, under the leadership of the BRD, form the communication link between the emergency area and the governmental emergency services in The Hague. The amateur emergency network was formed with The Hague as the central hub. Connections were possible with Terneuzen, Middelburg, Vlissingen, Goes, Raamsdonksveer, Dordrecht, Breda, Halsteren, Eindhoven, Krimpen aan de Lek, Hilversum, Amersfoort and the military station in Roosendaal. This amateur emergency communications network continuously operated for ten days.

His story: “In The Hague, 2 main transceivers and 1 secondary transceiver were established. The two main transceivers worked alternately, the secondary transceiver was operated by rotating teams. Amateurs from all parts of our country volunteered, and many of them went directly to the emergency areas with their mobile radio equipment sets.

On Monday, I went with the TNO colleagues from the Radio Group to Rotterdam. I stayed behind when the others left for Hellevoetsluis and Middelharnis. [see below]. In the afternoon, a telephone connection was established with the Ahoy halls [Rotterdam], another Red Cross shelter location. I returned home to The Hague in the evening, where I operated the 80 m emergency network under the supervision of the Chief of the Special Radio Service of the P.T.T. The P.T.T.  instantly installed open telephone lines in the homes of the two amateur radio operators connecting their operations with the Red Cross and the Netherlands Government Information Service.
[In an interview 50 years (2003) after the disaster, Sjors mentions that he immediately was sent home by his supervisor on Monday morning when arriving at the Laboratory. Sjors’s appendix to the report published within three weeks after the disaster is published here.]

On Tuesday morning, February 3, most radio amateurs had already arrived at their destination, the amateur emergency network was then running at full speed. The working hours of the first main transceiver station (Sjors) were 00:00 – 18:00, and then the main transceiver station number 2 took over from 18:00 – 00:00. I worked one day from 06:00 PM to 06:00 PM, then took a rest for 12 hours.
During the evening and at night, transmission at 80 m was not very suitable; the 160 m or 2 m band was much better, but the latter required far too complicated equipment for mobile amateur use.

The network was turned down on Tuesday 10 February at 2 AM only the links Vlaardingen – Ouddorp – Goederede and Wissenkerke – Rilland Bath remained.
After that, I resumed my normal activities at the Physics Laboratory.”

Surveillance of the 2-metre radio band

Shortly after hearing the first news about the disaster, the deputy director, his wife, and the laboratory driver went to the laboratory in Waalsdorp. There, attempts were made to contact radio amateurs located in the affected or neighbouring areas and operating in the 2 m radiofrequency band. Laboratory equipment for radio propagation tests, operating at a wavelength of about 2 m (144.00 MHz), was used. The aim was to relay any urgent messages about the need for assistance and the like.
However, the activity of radio amateurs was nil that afternoon. Neither were amateurs heard from other parts of our country attempting to achieve the same goal. There was nothing to hear throughout the entire band.
Only after some time, a radio station with call sign PA0FC from Maassluis in the affected area was heard. A connection was promptly established. The situation in Maassluis was not critical and the line telephone worked normally. Keeping this emergency transmission link open did not make much sense. After several hours of unsuccessful calling and listening, the transceiver was shut down. At 5.30 pm, the three people left for home.


Aid by the Radiogroup

Monday 2 February

In the morning, the radio group of the Physics Laboratory RVO-TNO spontaneously came up with ideas of ​​providing aid to the disaster areas in a different way. Since there was a large lack of communication with the affected areas, it was obvious to use the laboratory’s knowledge and equipment. Unfortunately, there was not much communication equipment available in the laboratory that was suitable for immediate use. The most suitable wavelength was the 80 m band. The only equipment that was immediately available and proved suitable for mobile use consisted of two Motorola V.H.F. transceivers operating at a wavelength of approximately 1.90 m (159 MHz) using frequency modulation. More than a year earlier, the equipment was lent to the laboratory by the former Technical Staff of the Royal Netherlands Army for an indefinite period. One decided to use this equipment. The transceiver power was supplied by batteries that had to be recharged with a battery charger after a day of use.

Contact was established with the Chief of the Special Radio Service of the P.T.T. He supervised a large emergency communication network in which radio amateurs, among others, played a major role. He gladly accepted the laboratory’s help. He directed our first team, consisting of six lab employees and a driver, to a Red Cross unit in the Feyenoord Stadium, Rotterdam, led by the commander of the Red Cross unit from The Hague, Dr J. de Ruiter. Transport was done with the lab-Ford auto driven by our laboratory driver. Departure from Waalsdorp was at approximately 11:30 AM. On this tour, they were accompanied by a passenger car of the P.T.T. Special Radio Service equipped with national mobile radio-telephone no.45.

We had to wait a few hours in Rotterdam as the relevant authorities were to be found nowhere. The Police Headquarters in Rotterdam received the indication that the village of ‘s-Gravendeel urgently needed a radio connection. Arriving there, the Mayor was delighted to be radio-connected. However, the village had already been evacuated for four-fifths of its population. Only one message had to be passed on: “No further help needed“.

Given the bad experiences with the official authorities, it was decided to form an independently operating group and to search on our own for a destination in need of aid. A leader was appointed by the group members. He decided to go to Hellevoetsluis without any delay to provide relief for the disaster isles Goeree-Overflakkee and Schouwen-Duiveland. On the trip to Hellevoetsluis, a message requesting drinking water and medicines was received from a radio telephone located in Bruinisse. The message was relayed via the mobile radiotelephone to Rotterdam. This was one of the first communication contacts with the flooded isle of Schouwen-Duiveland.

The group arrived in Hellevoetsluis at around 6.30 PM. It appeared that there was no direct radio or telephone connection with Middelharnis. A communication link was urgently needed because both the evacuation from and the flow of supplies to the isle of Goeree were concentrated on transport by ships between Hellevoetsluis and Middelharnis. The group decided to set up a permanent radio station in the tram station in Hellevoetsluis and to make their communication link available to the Mayor of Middelharnis. In the meantime, a helping hand was offered to bring a Netherlands Royal Navy transceiver into operation which had to contact a Navy operations base in the village of Stellendam.
When the transport by ship to Middelharnis proved possible at 11.30 PM, the group was split into two teams operating two transceiver stations. Radiostation 45A was installed in Hellevoetsluis, and radiostation 45B was made available to the Mayor of Middelharnis. The Special Radio Service employee joined radio station 45A. He would maintain contact with the hinterland using the mobile radiotelephone.

Tram station Hellevoetsluis
Tram station Hellevoetsluis
(source: voornewiki.nl)

Establishing the two radio stations

The dipole antenna of radiostation 45A was hung at the top of a lamppost. From 1 AM on, the transceiver was on every 15 minutes on the clock standby to make contact with Radiostation 45B.

At 00.15 AM, the group of radiostation 45B disembarked at the harbour head of the town of Middelharnis. Since there was no transport available, the Royal Navy at Middelharnis had to be warned on foot. The Royal Navy took care of the transport of the group and their equipment. At 03.15 AM, the group arrived at the town hall of Middelharnis (about 3 km from the harbour). In consultation with the Mayor, it was decided to install the radio station set-up in the council chamber. The radio station had to function as a permanent link across the Haringvliet between the towns of Middelharnis and Hellevoetsluis. Given the critical importance of this radio link for arranging supplies to, and evacuations from, the flooded areas on the isle of Goeree-Overflakkee. The antenna was placed on the bell tower of the town hall, at a height of about 20 metres.

Former city hall of Middelharnis directly after the flood (1953)
From the collection: De Watersnoodramp gefotografeerd. Tussen 1 februari en 7 februari 1953.

At 04:00 AM, the radio station 45B broadcasted for the first time. Almost immediately, to general relief and joy, contact with radio station 45A was achieved. From that moment on, the excellent connection has been in continuous operation. The entire evacuation of the isle via Middelharnis to Hellevoetsluis and the supply of food, clothing, medicines, sandbags, military assistance, Red Cross-aid columns and drinking water were arranged using this radio connection.

In addition to this extremely important function, the connection was also used for the transmission of messages to other towns such as Rotterdam, Utrecht, and The Hague. Moreover, the radio stations relayed messages for organisations such as the Government Information Service  Radio Hilversum [Radio news service], Scheveningen Radio, Red Cross, Ahoy halls, aeroplanes and helicopters as well as reports regarding the situation in various places on the island via the Government radio-telephone number 45.

Given the location of the two radio stations, the work of radio station 45B became more of a regulating and organising character, while radio station 45A was more likely to carry out or forward instructions given by radio station 45B by arranging the priority sequence of transports, ensure the presence of autobuses for the immediate transport of evacuees, requests for materials required on the islands (sandbags, petrol, etc.).

From the moment radio stations 45A and 45B were broadcasting, the activities of an each individual laboratory person were so intertwined with any other one that it was not possible to weigh each individual’s contribution to the ultimate success. The concerted effort of the employees made an important contribution to the relief efforts in the affected area and saved human lives.

Details of the work


In particular on Tuesday when virtually nothing had been organised yet, radio station 45A in Hellevoetsluis made certain that transports declared urgent by the Mayor of Middelharnis were shipped with priority (sometimes against the wishes of the Commander of the Royal Navy barracks in Hellevoetsluis). Their activity was beyond all praise. The autobuses were always present and ready for transport. It was always possible to transfer goods from transport trucks that were too heavy for the dyke in Middelharnis onto transport ships, and there was always a timely notification of the arrival of certain auxiliary equipment. Much help was received from military support personnel. The sergeant major of the Artillery responsible for the logistics has played a major role in these activities with his imperturbable calmness and tireless assistance. Mr. J.S. from Rhoon has functioned almost continuously as support to radio station 45A as the organiser of the transports. Nothing was too much or impossible for him. His organisation of the emergency transport to Den Bommel should be mentioned in particular.

Contact with the Royal Navy sometimes caused difficulties concerning the transports due to the arbitrary interventions by the Commander of the Royal Navy in Hellevoetsluis in loading civil ships and the order of transport. Although our radio station provided him with all communication facilities, he initially provided no cooperation. However, difficulties could sometimes be circumvented by the intervention of our team.

A DUWK (source: Collectie Nederlands Instituut voor Militaire Historie)
A DUWK (source: Collectie Nederlands Instituut voor Militaire Historie)

The work of radio station 45B in Middelharnis expanded very quickly. With the break of dawn, the influx of messages from the hinterland of Goeree-Overflakkee, and the requests for materials and supplies grew strongly. Although the general situation reports and supervision management directly were dependent on the instructions of the Mayor, the work of this radio station arranging the transport and supply took on a fairly independent character. Based on the knowledge from reports received about certain quantities of medicaments, materials, Red Cross personnel, petrol, oil, and the like stacked in various places on the mainland, the supplies could be directed directly by radio station 45B to places on Overflakkee where these supplies were requested.
Some statistics may give an impression of the volume of the transports processed by radiostations 45A and 45B: thousands of evacuees, tens of tons of food and children’s food, tens of tons of clothing and blankets, large quantities of connection material, hundreds of thousands of sandbags, medicines such as penicillin, blood plasma, etc., tens of light aggregates, thousands of litres of oil, petrol, aviation gasoline, etc., hundreds of water boots, ‘dukkos’ [“DUKWs“] and amphibious craft, hundreds of Red Cross men, nurses, dinghies, hulls, vans, draglines and bulldozers, coffins, thousands of iron road plates for the reinforcement of roads, thousands of litres of drinking water, hundreds of airport mats.

The communication network layout
The communication network layout
More communication links: TNO radio link as a spider in the web

The rapid expansion of the work and the lack of a good telephone connection made a separate connection with the jetty in the harbour very desirable. Particularly when, at the request of the Mayor of Middelharnis, a Lieutenant at Sea (LTZ 1) was appointed as coordination officer for the port of Middelharnis to regulate the ship traffic. On Tuesday evening, the Commandant of the Army Communication Unit was requested to provide SCR 300 sets for setting up a second communication network with our radio station 45B as the main post. The DEF station became the main post of this Army network. This network was also used to maintain connections with several relief teams. These teams had to relieve the villages of Oude and Nieuwe Tonge from isolation and provide assistance to Den Bommel where the situation had become critical. Their connection with the non-flooded Dirksland was very important because of the hospital in Dirksland. This connection could be maintained, albeit with great difficulty, via our mobile radiotelephony network with the mobile radiotelephone 38 in Mr. v.d. S’s Volkswagen. He was directed to go to the village of Dirksland. In addition, on Wednesday evening contact was made via this network with Herkingen using a private mobile radiotelephone 244 placed on a DUKW transport.

On the ferry that our group used to reach Middelharnis were also two Red Cross mobile transceivers with their operators. One of these transceivers was placed in another room of the town hall. This post had a problematic connection with the city of Vlaardingen (the main post of the Red Cross) and with its substation in the village of Den Bommel. However, when the situation in Den Bommel became critical on Tuesday night,  the operators of both radio stations appeared to have gone to bed. No contact could be made.

SCR-300 FM-transceiver
SCR-300 FM-transceiver

During the evening of Tuesday, February 3, a police station was put into operation in the town hall of Middelharnis. They acted as the central radio post having contact with its four outposts at Goeree, Stellendam, Ooltgensplaat and Oude Tonge. The messages intended for general information from these places were relayed by this police radio station to their main station in Vlaardingen. The requests for transports and supplies to and from the outpost locations were forwarded to Hellevoetsluis via our radio station 45B. In this way, supplies could be ensured through our communication channel. The operator who served at this police station did his work in an exemplary manner.

The above drawing of the network indicates the area that was covered and serviced from the Middelharnis town hall and where supplies and transports were provided via our transceivers.

To relieve the completely isolated population of Oude and Nieuwe Tonge from its isolation, the Mayor of Middelharnis decided to send some expeditionary teams on Wednesday. The communication with these teams would be maintained through radio station DEF with SCR-300 communication sets provided to the teams. Due to a lack of organisation, the first message from one of the teams could not be received until Wednesday evening.

The contact that could be maintained through our connection with operating aeroplanes and helicopters has been of great importance, as instructions and requests were very quickly communicated and processed through this radio channel, including:

  1. The fast supply and transport of blood plasma for the hospital in Dirksland.
  2. Reporting the distress of a ship carrying evacuees.
  3. Report the correct location of this ship (Hoornse Hoofden).
  4. Notification of a seaplane in distress.
  5. Instruction to an aeroplane about the location of a dropping zone and information about the success of the dropping. Only a few minutes elapsed between the initial request for determining a dropping zone, the instructions, the dropping itself, and the question about the success of the dropping by the aircrew and replying an answer.
  6. In the absence of authorities, the radio operator refused to transmit a non-authorised evacuation order  [see insert below].
  7. The organisation of droppings.
  8. Special urgent transport of medicines, etc.
  9. A telephone call from our main operator with the chief of the telephone district of Rotterdam (during the breakdown of the mobile radiotelephone connection on Tuesday as a result of the failing Rotterdam telephone system due to overloading), in which the managing crew was instructed to provide mobile radiotelephone traffic in the southern part of South Holland with the highest priority because of the urgency of the radiotelephone connections with the threatened areas. Half an hour later, mobile radiophony traffic was possible again.

Civil servant B., stated being a high representative of the Provincial Registry Agency, possessed a car with a mobile radiotelephone from the National Police with license plate HZ 4008. He arrived at radio station 45A at 7 PM and said that he had to pass on a very important message for the Mayor of Middelharnis in person: “On behalf of the Queen’s Commissioner I order you to continue the evacuation with vigor.”  The Mayor, however, went with other authorities to the jetty of Middelharnis to take inventory of the situation. Several hours earlier, he had ordered to halt further evacuation on Tuesday. This was told to B. He told the TNO operator to make the decision himself to continue the evacuation. He refused to communicate the order. Adoption of this order would have caused confusion, loss of time, and thus would have cost human lives. Afterwards it turned out that B. was a patient from the Rekkense Inrichtingen who was on probation. He appeared to radiate authority. He later welcomed the Queen’s Commissioner at the port of Hellevoetsluis, showed him around, and made his mobile radiotelephone car available to him. The police eventually sent B. back to the psychiatric clinic.

Wednesday, 4 February

To replace the first group of volunteers, a second group of seven coworkers from the radio group was directed to Hellevoetsluis. They were accompanied by the laboratory financial manager and a driver. At noon, the team left Waalsdorp using the Renault bus [and a private car] and arrived in Hellevoetsluis around 4 PM. A large quantity of materials including cables, lamps, gasoline emergency generator 220 V/1 kVA, flashlights, signal lamps, batteries and rectifiers was loaded. A portable transceiver operating in the 80-metre radio band and suitable for telegraphy was loaded as well. This transceiver was to keep in direct contact with the laboratory at Waalsdorp for relaying urgent messages, instructions, situation reports and the like. Many difficulties were avoided as the normal telephone network of the Rotterdam district was completely blocked [by overloading]. By the way, this transceiver was the private property of a coworker of the radio group. The transceiver was prepared for use during this emergency.
Around 4 o’clock, the replacement team arrived in Hellevoetsluis. The team was split into two groups. After 40 hours of service, the colleagues from radiostation 45A could be relieved. Radiostation 45A was now occupied in turns by the four coworkers of the first group. The replaced group from this radio station (45A) left for The Hague.

The radiostation 45A at Hellevoetsluis

Radiostation 45A had previously been installed in the Ford auto. Meanwhile, a small space in the tram station had been cleared for radio station 45A. The defective and borrowed battery charger was also replaced by a better one. During a transmission break in the evening, the transceiver was moved. This freed the Ford auto and made it possible to work with illumination. From this moment on, the messages were written on paper with an attached carbon copy. Recording the time of receipt and transmission plus the initials of the operator reduced the set of discussions. Messages not understood could now be verified.

During the first day and night, a lot of work was done by this group. The traffic volume was quite high. Since the operators did not know what the next day would bring, each member of the group slept approximately four hours a day. During the day, work was carried out with double occupancy, including the most necessary help to evacuees, and the loading and unloading of material. For example, lost troops of the Army communication unit were referred to the main location of their unit, lost material from citizens who had come to rescue was tracked down and registered. Three connection calls were made between the Kon. Mareschaussee (military police), the Special Radio Service of the P.T.T. and liaison troops from The Hague and the radio station 45B in Middelharnis.

Radio station 45B at Middelharnis

The replacement group for radio station 45B meanwhile took the next ferry to Middelharnis. The ferry left late. While waiting, the coworkers made themselves accustomed to the way of working. The crossing of the Haringvliet took place in the dark during snow and hail showers. A military truck brought the replacement group from the harbour to the village. The replacement group arrived at the Middelharnis town hall at 8:00 p.m. At 10:30 p.m., the radio station was taken over by the 3 coworkers forming the replacement group after technical and organisational briefings. The old operator crew of the radio station was able to get a few hours of sleep in the village of Sommelsdijk for the first time after installing and continuously maintaining 43 hours of radio contact [in Middelharnis there was no place to sleep]. The next morning they could return to Hellevoetsluis with the first ferry.

Beginning the first night our new operators served here, approximately 100 copies of telegrams were archived. Many messages, however, were passed on orally to the police radio station and to the military network station, which both were set up next to ours for this purpose. Our team was able to block, based upon information to us locally, the transmission of a lot of telegrams provided by authorised persons, as they were found to be based on incorrect information, which could have given rise to a panic mood. There were also many examples of incorrect denominations of goods requested for dropping. We have prevented several wrong shipments.

Thursday, 5 February

During the morning of the Thursday, the number of messages decreased as an increasing number of connection links came into operation. It looked like we soon could break up. The replaced crew of radio station 45B returned home in the evening.

Due to circumstances, the 80 m transmitter that was carried along could unfortunately not be put into operation until 3 PM on Thursday, 5 February. A connection with the laboratory in The Hague was made. During the evening some messages were sent across this link, using radiostation 45B as an intermediary radiostation. Thursday afternoon, the laboratory director Van Soest also went to Hellevoetsluis with four coworkers of the laboratory to be informed about the situation.

In the evening, the tasks had largely ended at the radio station 45B in Middelharnis because the telephone connections to the automated telephony network of the P.T.T. were restored. The PTT provided also some fixed telephone lines with The Hague and Utrecht. The crew of the radio station was no longer required to handle much traffic. The evacuation of the population [of Flakkee] was almost complete. The Mayor of Middelharnis decided it was time to say goodbye to all the volunteers and thank them for the services provided (during an evening meeting with all relief workers). The Commander of the Royal Navy barracks in Hellevoetsluis considered it necessary that both of our radio stations be kept operational for a short time; apparently, the Royal Navy had difficulties with their communication network.

A lot of improvisation by the first team was required based on a good situational understanding of the difficult local situation. The crews at both locations acted very independently and decisively. This was necessary in view of the somewhat stiff cooperation with some military authorities. They have been able to conveniently build a fairly extensive communications network using their own equipment, military equipment, the Government mobile radiotelephone number 45, some private mobile radiotelephones and a police post. The transport of supplies and the like came to rest on their shoulders. The group in Hellevoetsluis can be regarded as the ‘forward crew’ of the Mayor of Middelharnis. By using the services of citizens of Hellevoetsluis in a clever and handy manner, the crews have been able to achieve a great deal in a particularly rapid manner.

Friday, 6 February

Because the normal telephone connection between Middelharnis and Hellevoetsluis had been restored, the crew of radiostation 45A had no longer much traffic to pass on. At 11:00 AM, the Commander of the Royal Navy barracks in Hellevoetsluis decided that our transmission link was no longer required. We were thanked for the rendered services.

Attempts were made to inform the laboratory in The Hague via the 80 m transceiver. No connection could be made. We did not receive a reply for a long period. The ‘portable’ transmitter at the laboratory did not work well. We decided to break up.

The radio station 45B in Middelharnis broke up at 11 AM. At 11.45 AM all equipment was packed. A captain of the Military Police provided his jeep for the transport to the harbour. At noon, the crew was at the jetty where the ferry just had arrived. The team arrived in Hellevoetsluis at approximately 2 PM. We managed to charter a military truck, the driver of which was kind enough to bring our equipment and a coworker to Waalsdorp.
At about 3.30 PM, both teams with their private materials could return to The Hague using their car, the laboratory Ford and the Renault bus.

Radio support at the laboratory (February 3 – 6 and 16 – 17, 1953)

From Tuesday morning on, we managed to receive the transmissions of our radio stations in Middelharnis and Hellevoetsluis using a sensitive FM receiver in the laboratory. This made it possible to immediately forward an urgent emergency message from a sinking ship with evacuees. Tuesday afternoon, a telegraphy transmitter was set up with an antenna power of approximately 100 W, also operating in the 80-metre radio band. A small transceiver set (MK 22) was ready as a backup for immediate use from 4:00 p.m. onwards.

From time to time, contact was made with the telegraphy transmitters of the mobile Red Cross stations PA0FY (Rotterdam), PA1FY1 (Oude Tonge; later Zierikzee) and PA1FY3 (Dintel emergency harbour). It was agreed that in case of any difficulties in the Red Cross network, our transmitter setup would pass on messages. Fortunately, that had not been necessary.

On request, some communications from this network to the Government Information Service and to some family members were relayed by us. We also used our 80 m transmitter to keep the channels of the Red Cross stations and our channel (3,579 kc/s) as much as possible ‘clean’. To this end, several other transmitters were successfully requested to change their wavelength.
Reports were received that the station was heard with great strength in Berlin, Nienburg (Weser), Mönich and England.
The transmitter was in operation 24/7. Two employees operated the receiver, which was tuned to the radio stations Middelharnis and Hellevoetsluis, at night as a listening watch.

On Friday at 10:15 AM, a connection with per 80 m transceiver was made with the replacement group; some information was exchanged. After that, no sign of the replacement group was heard on the 80 m, although we continuously monitored the transmission frequency until around 4 PM. Due to the inoperability of this connection, we lost track of the situation. It later turned out that the team activities had ended at noon. As it was not yet certain whether or not others required the use of the emergency communication services, it was decided to send a replacement group of five coworkers just to be sure. This replacement group comprised of those of the initial Monday relief group.
At 18.00 both groups (first and second replacement groups) arrived at Waalsdorp. This ended our radio transmission services in the disaster area.

Again “dike monitoring”: During the night of 16 to 17 February 1953, the laboratory was stand-by in the amateur emergency network operating at 3,700 KHz (80-metre radio band) at the request of the Chief of the PTT Special Radio Service on behalf of the Director-General of the P.T.T.

Other relief activities by the Physisch Laboratorium personnel

Dike reinforcements on the island of Putten

Early in the morning of Monday (February 2), 13 people, including a first-aid worker, left the Physics Laboratory to Spijkenisse by the laboratory’s car (a Renault) with a set of spades. From there the people helped with the dike reinforcement activities on the island of Putten. In the afternoon, the car returned and brought in a second crew of fourteen laboratory workers with spades.
In the evening, the car returned a third time to the emergency area with four persons including the manager of the earlier teams. Some of the staff returned with this car late at night. Others came back by “hitchhiking”. A few remained for another day.

On Monday at noon we left with a group armed with boots and a spade each with the Renault bus to the village of Rhoon. There we had to report to the town hall. I remember that opposite the town hall there were a lot of cows roaring on a lawn. The cows needed to be milked. We were instructed to fill sandbags. It was a big mess. I lost my group and the spade. With a truck, I went to the gaping hole in the dike to throw in filled sandbags. We were making no headway at all because the sandbags disappeared in the strong currents. Around 3 AM, I noticed a truck from Scheveningen. I returned home with that truck. [testiomony from a former employee in 2020]

Other individual contributions

Other members of the staff have provided help on their own in various areas: as a driver in transporting sandbags; as a dike guard at Oud-Beierland, as a dike guard at the dikes of Putten and IJsselmonde, as a driver of a Renault motorcar to transport injured people from Putten to IJsselmonde, and for rescue work and dike improvement at IJsselmonde.
Three soldiers seconded to the laboratory were called up for military services in The Hague.


The report mentions many people from other organisations by name. They are thanked for their support and cooperation. This gratitude includes e.g. the caretakers of the tram station in Hellevoetsluis (coffee, bread and the like), civilian, Army and Navy liaisons, and the PTT mobile radio-telephone operators working for the Government, and Mr Dirk Rijnders, Mayor of Middelharnis and his staff.


“Hulpverlening door het Physisch Laboratorium RVO-TNO bij watersnoodramp 1953”, Physisch Laboratorium RVO-TNO, Den Haag, Rapport 1953-6, 19 februari 1953.