Monthly maps for discharge anomalies and Lowest alert level exceedance with a summary of the monthly hydrological situation.


Hydrological situation for April 2022

Figure 1. Exceedance of lowest discharge threshold level for April 2022.
Figure 1. Exceedance of lowest discharge threshold level for April 2022.
Figure 2. Exceedance of lowest water level threshold level for April 2022.
Figure 2. Exceedance of lowest water level threshold level for April 2022.
Figure 3. Classification of stations according to discharge historical data average percentile ranges for April 2022.
Figure 3. Classification of stations according to discharge historical data average percentile ranges for April 2022.

by EFAS Hydrological Data Collection Centre

During the month of April, there were 94 stations with exceedances. The majority of these stations with exceedances are in Spain, with 20 stations across 14 basins. Many of the stations are discharge exceedances, centered in the northeast region (Ter and Llobregat basins) and in the east, where we find several basins. Regarding water level values, only one station in Guadalorce basin presents an exceedance and the rest are situated in the Ebro basin.

Additionally, there is a large concentration of stations in Italy (Po and Tiber basins), and in Ukraine (mainly in the Danube and Dnieper basins and to a lesser extent on the Don and Dniester).  Nine exceedances can be found in Germany, centered on the Rhine basin. There are also some countries with exceedances at more than two stations, such as Poland (7), Croatia and Bosnia and Herzegovina (6), Slovakia (5), and Serbia (4).  Sweden, Romania, and Georgia all have two stations with exceedances.

In terms of river basins, the two prominent basins with values above the threshold are the Danube (with 27 stations) and the Po (with 13 stations).

Regarding the stations that recorded values above the 90% quantile, 55 exceeded this threshold in April. Twenty-five of them are located in Spain, in the south and east. The basin with the highest number of stations in Spain is the Jucar Basin, with 10. The Mijares, Guadalhorce, Guadalquivir, and Ebro Basins have more than one station with exceedances. The Scandinavian peninsula is once again an area with the most stations exceeding this quantile; where Sweden has eight stations, followed by Finland with seven, and Norway with the three stations.

By basins, in addition to the aforementioned Jucar and Mijares, there are those of the Torne rivers (4 stations) and those of the Rhine and Tana (3 stations each).
Additionally, other stations exceeding the 90% quantile value are found in France, Ukraine, Iceland, Italy, Germany, Austria, Latvia, and Luxembourg. 

Finally, and according to the number of stations recording mean values below the 10% quantile, we find a decrease of more than 50%. In the month of April, there are only 60 stations with mean values below this quantile.

Germany is the country with the most stations (11) followed by Spain (10), which continues to reduce the number of stations in this month (about half of March). Norway presents a similar number of stations (9), and seven stations are found in Italy. In terms of basins, the Danube is again the watershed with the highest number of stations, but with one-sixth of the previous month and mainly centered on Germany and Austria.

Lastly, the Elbe and Oder river basins present six and five stations with values below the 10% quantile, respectively. Lastly, presenting four stations each, it is worth mentioning the Po river (Italy) and the Dnieper river (Ukraine).