2024 Switzerland floods#21 and 22 June
{{Short description|2024 Natural disaster in Switzerland}}
{{Infobox event
| date = 1 – 30 June 2024
| image = Maschwander_Allmend_Hochwasser_20240601_05.jpg
| partof = 2024 European floods
| caption = Flooding of the Maschwander Allmend in the canton of Zug
| Location =
| type = Heavy rainfall
| reported deaths = 18
| reported injuries =
| missing =
| property damage =
| displaced =
}}
In June 2024, a series of storms such as storms caused major damage in various regions of Switzerland through flooding, landslides and mudslides and claimed at least eighteen lives.{{Citation needed|date=September 2024}} The disruption to the transport infrastructure also has an impact on transit traffic with the interruption of the A13 motorway and on tourism in parts of the Swiss Alps.
Floods from 1 June
{{see also|2024 Germany floods}}
In early June, there was heavy rainfall, especially in southern Germany, but also in neighboring regions, which caused flooding in numerous regions. Rivers such as the Rhine and the Reuss caused local flooding, the water level in Lake Constance rose; danger levels 4 and 5 (high and very high danger) were reached, respectively, before being lowered to level 3. The danger on Lake Constance remained elevated until the end of June. The ground was still wet in many places; there was a lot of fresh snow in the high mountains.
Heavy rainfall, especially on Saturday, 1 June and Monday, 3 June, caused rivers and lakes to rise; there was a flood alert on the Sitter and Goldach in eastern Switzerland, danger level 3 (significant danger) was in effect on Lake Constance and the Upper Rhine, and danger level 4 (high danger) on Lake Constance on 4 June.{{cite web |url=https://www.tagblatt.ch/ostschweiz/ressort-ostschweiz/ostschweizer-wetter-ticker-gefahrenstufe-4-untersee-tritt-in-berlingen-uebers-ufer-noch-ist-vorsicht-geboten-in-gewaessernaehe-entwarnung-fuer-die-sitter-und-die-thur-ld.2625517 |title=Hochwassergefahr in der Ostschweiz: Aktuelle Lage im Ticker |publisher=Online-Redaktion |date=2024-06-04 |language=de |accessdate=2024-06-04}} the Untersee in Berlingen and the Rhine in Bad Zurzach overflowed their banks.{{cite web |url=https://www.watson.ch/!752893423 |title=Erdrutsche und Hochwasser in der Ostschweiz – Keller unter Wasser in Zug |language=de |accessdate=2024-06-04}} Lake Lauerz in the canton of Schwyz overflowed its banks and the flooding of the Reuss caused flooding on the Maschwander Allmend in the cantons of Zug and Zurich. In the cantons of Zurich (450 operations), Thurgau (150 operations) and St. Gallen (90 operations), fire brigades were called out over the weekend because of water in buildings and flooded streets. Apart from the flooding, there were various landslides.{{cite web |url=https://www.srf.ch/news/schweiz/wetterberuhigung-hochwasser-schweiz-situation-duerfte-sich-heute-entspannen |title=Wetterberuhigung – Hochwasser Schweiz: Situation dürfte sich heute entspannen |date=2024-06-03 |language=de |accessdate=2024-06-04}} In St. Gallen, the CSIO Nations Cup was cancelled on Friday. Compared to Bavaria, however, the whole thing went relatively smoothly, although heavier rainfall had been forecast beforehand.
Heavy rainfall on 9 and 10 June caused water levels to rise and local flooding throughout western and northern Switzerland. In addition to Lake Constance, there is also flooding on Lake Zurich and Lake Lucerne and their outflows.{{cite web |access-date=2024-06-10 |title=Hydrologisches Bulletin |url=https://www.hydrodaten.admin.ch/de/bulletin |work=hydrodaten.admin.ch}} On 11 June, a flood warning of danger level 5 was issued for the Untersee, making it the highest of all danger levels (very high danger).{{cite web |url=https://www.srf.ch/news/schweiz/bund-setzt-gefahrenstufe-5-sehr-grosse-hochwassergefahr-fuer-den-untersee |title=Bund setzt Gefahrenstufe 5 – Sehr grosse Hochwassergefahr für den Untersee |work=srf.ch |date=2024-06-11 |accessdate=2024-06-11}} On 13 June, the flood levels at Upper Lake and Lower Lake of Lake Constance were each at level 4; after a temporary easing, the water levels rose again during the storm on 21 June 2024.
21 and 22 June
Around 20 June, there was another weather situation with a low pressure area and a strong southerly flow, which brought moist air masses into the Alpine region. On Friday, 21 June 2024, a thunderstorm front brought persistent heavy rainfall in the Alpine region and also in the Jura Mountains and in areas near the border of neighboring countries.{{cite web|url=https://www.meteoschweiz.admin.ch/ueber-uns/meteoschweiz-blog/de/2024/06/unwetter-gewitter-sueden.html|title=Rückblick auf die Gewitterlage vom 21. Juni 2024 auf der Alpensüdseite.|publisher=MeteoSchweiz}} In the Grisons mountain valley of Valle Mesolcina, 125 mm of rain fell within 24 hours.{{cite web|url=https://www.watson.ch/schweiz/wissen/842991202-wie-kam-es-zu-diesem-verheerenden-unwetter |title=Wie kam es zu diesem verheerenden Unwetter?|publisher=Watson|date=24 June 2024}}
The unstable weather situation prevailed for several days; on the evening before 25 June, a heat thunderstorm brought large amounts of rain, especially in the canton of Vaud (117 mm in 3 hours in L'Auberson) and in the canton of Basel-Landschaft (53 mm in 3 hours in Liestal).{{cite web |url=https://www.srf.ch/meteo/meteo-stories/zahlen-und-bilder-heftige-gewitter-am-dienstagabend-in-der-schweiz |title=Zahlen und Bilder. Heftige Gewitter am Dienstagabend in der Schweiz |work=SRF Meteo |date=2024-06-25 |language=de |accessdate=2024-06-26}}
= Rhine region =
The flooding of the Rhine caused the water level of Lake Constance to rise again, as it had at the end of May 2024, so that the Swiss authorities declared danger level 4 for the lake shores and the Upper Rhine. All people were asked to stay away from the lake and river banks for their safety. Until Monday, 24 June, the water in Lake Constance continued to rise; at the Berlingen gauge on the Untersee, the water level was measured at 396.95 m above sea level (normal monthly average: 396.07 m above sea level).{{cite web |url=https://www.hydrodaten.admin.ch/de/seen-und-fluesse/stationen-und-daten/2043 |title=Station 2043: Bodensee (Untersee) – Berlingen |work=Hydrologische Daten und Vorhersagen |publisher=Bundesamt für Umwelt (BAFU) |accessdate=2024-06-25}}
= Valais =
In Valais, so much water flowed from the mountain torrents into the Rhône that it reached its highest levels near Sion and in the Lower Valais; at the Fully gauge station,{{cite web |url=https://www.hydrodaten.admin.ch/de/seen-und-fluesse/stationen-und-daten/2024 |title=Station 2024: Rhône – Branson|work=Hydrologische Daten und Vorhersagen |accessdate=2024-06-25}} a discharge of 819 m3/s was measured on 22 June 2024, which corresponds to a once-in-a-century event.{{cite web|url=https://www.hydrodaten.admin.ch/documents/Hochwasserstatistik/2024hq.pdf |title=Probabilité des crues (crues annuelles) |work=Hydrologische Daten und Vorhersagen |accessdate=2024-06-25}} In the Chablais above Lake Geneva, the discharge of the Rhône temporarily reached 1200 m3/s, according to information from the cantonal management staff of the canton of Vaud. At the mouth of the Rhône in Lake Geneva, large masses of driftwood collected on a floating barrier. In Chippis, more than 200 residents had to leave their houses in the vicinity of the river.{{cite web|url=https://www.lenouvelliste.ch/valais/valais-niveau-dalarme-et-situation-particuliere-maintenus-1398548|title=Valais: niveau d’alarme et situation particulière maintenu.|publisher=Le Nouvelliste|date=22 June 2024}}{{cite web|url=https://www.nzz.ch/panorama/weltuntergangsstimmung-nach-unwetter-im-wallis-im-wasserschloss-europas-kam-so-viel-wasser-wie-lange-nicht-mehr-ld.1836338|title=Entwarnung im Wallis: Das Hochwasser geht zurück.|author=Patrick Gasser|publisher=Neue Zürcher Zeitung|date=23 June 2024}} The Nufenen Pass was temporarily closed on 21 June as a result of a landslide.{{cite web |url=https://www.nau.ch/news/schweiz/erdrutsch-am-nufenenpass-zwischen-wallis-und-tessin-66783637 |title=Erdrutsch am Nufenenpass zwischen Wallis und Tessin |work=Nau |date=2024-06-21 |accessdate=2024-06-29}}
In Mattertal, the level of the Mattervispa rose so much that the stream flooded streets near the banks in Zermatt and the ground floors of several buildings. The Triftbach, which flows into the Mattervispa in the center of Zermatt, also overflowed its banks. Landslides interrupted the route of the Matterhorn Gotthard Bahn between Visp and Täsch and also the cantonal road in the Mattertal, so that Zermatt was cut off from the outside world. Near Randa, a mudslide from the village stream buried the main road, and near Herbriggen, a second mudslide buried the road and the railway line.{{cite web|url=https://pomona.ch/story/437694/gemeinde-zermatt-informiert-über-die-aktuelle-situation|title=Bahntrassee meterhoch verschüttet|work=pomona.ch|date=22 June 2024}} In some places, the Mattervispa undermined the railway tracks. In Visp and Täsch, tourists who wanted to get to Zermatt or leave the Mattertal were blocked. The Gornergrat Railway also had to temporarily cease operations because the Riffelbord protective gallery had been damaged by a landslide. In the following days, the Matterhorn Gotthard Bahn reopened the line from Zermatt to Täsch, while buses ran between Täsch and Visp as a replacement for the interrupted railway line after the debris cones from the mudslides on the cantonal road had been cleared.
The most extensive damage in Valais was caused by flooding, mudslides and inundation in the Val d'Anniviers. The Navizence valley river carried about as much water as during the last serious flood event in 2018. The drinking water supply, sewage pipes and power lines of the holiday resort of Zinal were damaged. The cantonal road between Vissoie and Mayoux was temporarily impassable.{{cite web|url=https://www.lenouvelliste.ch/valais/valais-central/sierre-district/anniviers/intemperies-les-travaux-de-remise-en-etat-commencent-en-anniviers-1398711 |title=Intempéries: les travaux de remise en état commencent en Anniviers.|author=Alexandre Beney|publisher=Le Nouvelliste|date=23 June 2024}} The drinking water supply in Evolène was also disrupted.
= Valle Mesolcina =
In Valle Mesolcina, floods and mudslides caused severe damage over a length of 20 kilometers. The Moesa, which drains the valley to the Ticino, led to a rapid rise in the water level of 650 m3/s at the Lumino/Sassello gauge station on the evening of 21 June 2024.{{cite web|url=https://www.hydrodaten.admin.ch/de/seen-und-fluesse/stationen-und-daten/2420|title=Moesa – Lumino, Sassello 2420. Hydrodaten.|publisher=Bundesamt für Umwelt (BAFU)|date=25 June 2024}} During the night of 22 June, rock avalanches and masses of mud fell on several mountain slopes in the municipalities of Lostallo and Soazza, flooding cultivated land. The wastewater treatment plant in Lostallo was flooded, all four of the municipality's balancing basins were full of debris and had to be dredged.{{cite web|url=https://www.bernerzeitung.ch/lostallo-gemeindepraesident-nicola-giudicetti-ueber-das-unwetter-658287405068|title="Der Fluss wurde so hoch, dass er die Autobahn mitspülte".|author=Rico Bandle|publisher=Berner Zeitung.|date=22 June 2024}} Several hydroelectric power plants owned by the energy company Axpo had to cease operations; dozens of people were evacuated from their homes.{{cite web|url=https://www.gr.ch/DE/institutionen/verwaltung/djsg/kapo/aktuelles/medien/2024/Seiten/202406223.aspx|title=Misox: Hochwasserlage.|publisher=Kantonspolizei Graubünden|date=22 June 2024}}
In the hamlet of Sorte (430 m above sea level), three kilometres south of Lostallo, buildings were destroyed when a devastating mudslide from the Val de la Molera, on the west side of the Mesolcina beneath the Piz della Molera (2603 m above sea level) and the Piz de Groven (2694 m above sea level), flowed through the settlement. The Rià de la Molera torrent, or Riale Molera in Italian, begins in the mountain valley in the municipalities of Cama and Santa Maria in Calanca and flows into the Moesa from the right near Sorte, a district of the municipality of Lostallo; West of the river bridge (401 m above sea level), the younger part of the village, Campagna de Sort, stands on the old debris cone of the stream, which was created by earlier mudslides, on the Hauptstrasse 13 and at the former stop of the former Mesolcina railway. The mountains in this section of the Mesolcina consist of granite and gneiss formations. Because the water-soaked loose material in the Molera valley became unstable, a mud and rubble avalanche, which also carried away large boulders, started in the mountain area. The debris avalanche broke out of the previous stream bed, covered the meadow area and destroyed several houses in Sorte, interrupted the cantonal road and buried the western bridgehead of the Moesa bridge.{{cite web|url=https://edit.geo.gr.ch/s/Mmo8|title=Oberflächengewässer|publisher=Geoportal der kantonalen Verwaltung|location=Grisons|accessdate=26 June 2024}}{{cite web|author=Sven Titz (u. a.)|url=https://www.nzz.ch/wissenschaft/geroelllawine-im-misox-wie-es-dazu-kam-und-warum-niemand-damit-rechnete-ld.1836462|title=Gerölllawine im Misoxtal: was sie so zerstörerisch gemacht hat und warum sie unerwartet kam.|publisher=Neue Zürcher Zeitung|date=25 June 2024}} At least one person from the hamlet lost their life, another person was rescued alive from a damaged house.{{cite web|url=https://www.cdt.ch/news/abbiamo-trovato-una-salma-356035|title=Mesolcina «Abbiamo trovato una salma».|publisher=Corriere del Ticino|date=23 June 2024}}{{cite web|url=https://www.suedostschweiz.ch/graubuenden/aufraeumarbeiten-laufen-in-der-bildergalerie-so-zeigt-sich-die-region-moesa-nach-den-unwettern|title=In der Bildergalerie: So zeigt sich die Region Moesa nach den Unwettern.|publisher=Die Südostschweiz|date=23 June 2024}} Two people remain missing.{{cite web |url=https://www.br.de/nachrichten/deutschland-welt/vermisste-nach-unwettern-in-der-schweiz-zermatt-abgeschnitten,UGPYiWc |title=Ein Toter nach Unwettern in der Schweiz – noch zwei Vermisste |work=br.de |date=2024-06-23 |accessdate=2024-06-24}}
File:Severe weather damages A13 Buffalora June2024 Swisstopo Rappid Mapping.jpg
File:Val de la Forcola LBS R1-941097.jpg
As a result of a particularly strong flood from the Val d'Orbel, the Moesa was dammed above the Buffalora bridge on the A13 motorway, flooding the motorway and eroding its ramp over a distance of around 150 metres. In this section in the municipality of Soazza, the river valley is designated as the "Pomareda" nature reserve in the Federal Inventory of Floodplain Areas of National Importance.Objektblatt {{cite web|url=https://data.geo.admin.ch/ch.bafu.bundesinventare-auen/objectsheets/2017revision/nr162.pdf|title=Pomareda|publisher=Bundesinventar der Auengebiete von nationaler Bedeutung}} The Val d'Orbel stream on the east side of the valley carried debris with a volume of around {{cvt|50,000|m3|abbr=on}} due to the rainfall.{{cite web|url=https://www.cdt.ch/news/i-lavori-dureranno-almeno-un-mese-a2-a-rischio-paralisi-356066?cx_experienceId=EXL2ASBTAEF5&cx_experienceActionId=showRecommendationsVDO63W1RA6OP58#cxrecs_s|title=L’emergenza. «I lavori dureranno almeno un mese»: A2 a rischio paralisi.|first=Francesco|last=Pellgrinelli|publisher=Corriere del Ticino|date=23 June 2024|language=it}} In 2019, a mudslide from the same stream channel had already caused flooding of the floodplain area next to the motorway at this point during a flood on the Moesa.{{cite web|url=https://www.watson.ch/schweiz/klima/477982432-a13-im-misox-zerstoert-was-das-mit-der-renaturierung-zu-tun-hat|title=Was die Renaturierung der Moesa mit der Zerstörung der A13 zu tun hat.|first=Pascal|last=Ritter|publisher=Watson|date=28 June 2024}}
The Hauptstrasse 13 and some municipal roads in the Mesolcina were impassable due to mudslides.{{cite web|url=https://www.cdt.ch/news/se-la-natura-ha-sempre-lultima-parola-356094|title=Se la natura ha sempre l’ultima parola.|first=Paride|last=Pelli|publisher=Corriere del Ticino|date=24 June 2024}} For safety reasons and because of the clean-up work, the main road between Mesocco and Lostallo was closed in the following days.{{cite web |url=https://www.gr.ch/DE/institutionen/verwaltung/djsg/kapo/aktuelles/medien/2024/Seiten/202406243.aspx |title=Misox: Hochwasserlage – Übergabe an regionale Krisenorganisation |publisher=Kantonspolizei Graubünden |date=2024-06-24 |accessdate=2024-06-26}}{{cite web |url=https://strassen.gr.ch/sites/strassenzustand/zustandsmeldungen.html |title=Graubünden Strasseninfos – Unser Kanton |publisher=Website des Kantons Graubünden |accessdate=2024-06-26}}
Federal Councillor Ignazio Cassis visited the damaged areas in the valley together with the Grisons government councillor Jon Domenic Parolini, the Ticino State Council President Christian Vitta and other members of the authorities.{{cite web|url=https://www.cdt.ch/news/un-tragico-destino-ha-travolto-sorte-e-scioccante-da-pelle-doca-356057|title=«Un tragico destino ha travolto Sorte, è scioccante, da pelle d’oca».|first1=Irene |last1=Sorali |first2=Jenny |last2=Covelli|publisher=Corriere del Ticino|date=23 June 2024}} The cantonal authorities planned to repair the damage to the infrastructure in the Sorte-Lostallo-Cabbiolo area as a first priority in order to make local traffic in the valley possible again, while the roads in the area above from Soazza to Mesocco were given second priority. The Swiss Army set up an air bridge with helicopters between Mesocco and Roveredo for emergencies.
Because of the destruction of the road, the authorities closed the A13 near Thusis in the north and Lostallo in the south. The north-south route through the San Bernardino tunnel, which often carries around 15,000 vehicles a day in the summer months, was unusable for around two weeks. Because the expected increase in traffic through the Gotthard would hardly be able to be managed with the Gotthard Road Tunnel,{{cite web|url=https://www.srf.ch/play/tv/tagesschau/video/tagesschau-vom-23-06-2024-hauptausgabe?urn=urn:srf:video:0eab6560-230a-43fb-b5d1-050858039f66|title=Mega-Stau wegen gesperrter A13?|publisher=SRF Tagesschau|date=23 June 2024}} the Federal Council planned to reach an international traffic agreement with neighboring countries in order to distribute the travel through the Alps to the other Alpine passes during the summer.
On 24 June, excavation work began to clear the blocked riverbed of the Moesa near Buffalora in order to then repair the damaged motorway embankment.{{cite web |url=https://www.admin.ch/gov/it/pagina-iniziale/documentazione/comunicati-stampa.msg-id-101566.html |title=A13 Lostallo Mesocco: avviata la ricostruzione dell’autostrada |work=admin.ch |date=2024-06-24 |accessdate=2024-06-25}} Large boulders were blasted away.{{cite web |url=https://www.srf.ch/news/schweiz/nach-unwettern-a13-durch-misox-in-zwei-wochen-wieder-einspurig-befahrbar |title=Nach Unwettern. A13 durch Misox in zwei Wochen wieder einspurig befahrbar |work=SRF News |date=2024-06-26 |accessdate=2024-06-26}} A single-lane reopening of the road was expected by 5 July, after initially aiming for 10 July.{{cite web |url=https://www.srf.ch/news/schweiz/nach-unwettern-im-misox-autobahn-a13-bereits-ab-5-juli-wieder-einspurig-befahrbar |title=Nach Unwettern im Misox. Autobahn A13 bereits ab 5. Juli wieder einspurig befahrbar |work=SRF News |date=2024-06-28 |accessdate=2024-06-28}} On 26 June, the Ticino cantonal government decided to transfer 80,000 francs in emergency aid to the Mesolcina region in the neighbouring canton of Grisons.{{cite web|url=https://www.laregione.ch/cantone/ticino/1765478/donazione-ticino-mesolcina-franchi-80mila|title=Dal Ticino 80mila franchi a favore della Mesolcina.|publisher=laRegione|date=26 June 2024}}
25 and 26 June
On 25 June 2024, another thunderstorm zone with heavy rain moved from the southwest over parts of Switzerland. Shortly after 10 p.m., the air traffic control company Skyguide temporarily closed Geneva airspace due to flooding in the basement of the control center, as the cooling of the data center had been impaired. As a result, take-offs and landings could no longer take place at Geneva Airport. Flooding occurred in Liestal and Morges, among other places. According to information from Alertswiss, there was a partial power outage in the Stein am Rhein/Ramsen area.{{cite web |url=https://www.srf.ch/news/schweiz/unwetter-in-der-schweiz-skyguide-sperrt-luftraum-genf-hochwasser-bei-basel-und-morges |title=Unwetter in der Schweiz. Skyguide sperrt Luftraum Genf +++ Hochwasser bei Basel und Morges |work=SRF News |date=2024-06-26 |accessdate=2024-06-26}}
29 and 30 June
In advance, warnings had already been issued of renewed storms with heavy rainfall and a foehn storm in the Alps for 29 and 30 June 2024. As a result, the cantonal authorities of Geneva and Vaud banned all outdoor events as a precautionary measure on 29 June. In both cantons, public viewing of the UEFA Euro 2024 was particularly affected by the event bans.{{cite web |url=https://www.srf.ch/news/schweiz/schwere-unwetter-erwartet-genf-und-waadt-sagen-alle-veranstaltungen-im-freien-ab |title=Schwere Unwetter erwartet. Genf und Waadt sagen alle Veranstaltungen im Freien ab |work=SRF News |date=2024-06-29 |accessdate=2024-06-29}} The canton of Valais, in turn, warned of flooding and mudslides.{{cite web |url=https://www.tagesanzeiger.ch/am-samstag-drohen-gewitter-in-der-schweiz-197001626106 |title=Am Samstag drohen Gewitter in der Schweiz |work=Tages-Anzeiger |date=2024-06-29 |accessdate=2024-06-29}} In large parts of Switzerland, danger level 3 or 4 (significant or great danger possible) was in effect on the afternoon of 29 June.{{cite web |url=https://www.meteoschweiz.admin.ch/service-und-publikationen/applikationen/gefahren.html |title=Gefahren |work=MeteoSchweiz |accessdate=2024-06-29}}