Dam failure in Ukraine
Satellite images show the flood zone on the Dnipro
By Martin Morcinek and Laura Stresing
6/6/2023, 7:31 p.m
The Kachowka dam bursts, enormous masses of water roll through the south of Ukraine. Which localities between Nowa Kakhovka and the Dnipro estuary near Cherson are affected? Satellite images and maps provide an overview of the affected area.
In the middle of the war, Ukraine is confronted with a catastrophic flood: In the south of the country, the Kakhovka Dam, which is under Russian control, collapses. Since the early morning hours of June 6, the dammed water from the Kakhovka reservoir has been pouring into the lower reaches of the Dnipro.
The Kachowka reservoir goes back to a gigantic mammoth project from Soviet times: a good three-kilometer-long dam structure dams the Dnipro here to form the largest and longest inland body of water in Ukraine. The Kachowka reservoir is a good 230 kilometers long and up to 20 kilometers wide – and thus longer and wider than Lake Garda and Lake Constance together.
Before and after pictures of the dam collapse:
Current satellite images show the extent of the destruction at the Kachowka Dam. The recordings on the left are from Sunday 4 June. The high-resolution camera eyes of an earth observation satellite show a damaged but still functional barrier.
At least two of the dam’s flood gates are open. Water apparently flows in a controlled manner into the lower reaches of the Dnipro near Nowa Kakhovka. The satellite photo on the right, on the other hand, was taken around noon on June 6, a few hours after the dam burst. You can see a powerful torrent of water rolling downstream through a gap in the dam several hundred meters wide.
The Kakhovka dam and hydroelectric power station had been under Russian control since the first days of the war. The town of Nowa Kakhovka on the left, southern bank of the Dnipro is of great strategic importance: until last autumn, one of the few road bridges crossed the river here.
Since the retreat of Russian troops across the Dnipro last fall, the lower reaches of the river have formed part of the more than 1,000-kilometer-long front line. Units of the invading army blew up the last remaining lane in the immediate vicinity of the dam in November. Since then the structure has remained damaged.
Repair work was next to impossible so close to the front. However, the hydroelectric power station continued to provide electricity to parts of southern Ukraine. Irrespective of this, the dam plays a vital role in the Russian invasion plans: the North Crimean Canal branches off just above the barrage.
Large parts of the water supply in Crimea depend on a stable water level in the reservoir. The Crimean Canal also supplies the extensive areas of irrigated farming in the steppe region between Cherson and Melitopol. The problem: The Crimean Canal is fed from the reservoir of the Kachowka reservoir. If the water level drops, the canal dries up.
A view of the flood zone on the lower reaches of the Dnipro:
On the Map the entrance to the Crimean Canal is clearly visible to the right of the dam. To the west of the barrage, i.e. below the dam wall, high-voltage lines run from south to north across the river valley.
Satellite images from late May and early June show that the structural condition of the barrage has deteriorated over the past few days. You can see two open flood gates, through which the spring melt water flows off. Immediately next to it, part of the road construction has apparently collapsed. This incident must have happened between May 28th and June 5th.
Damage visible before the dam burst:
The tidal wave from the Kachowka reservoir will most likely hit the left bank harder than the opposite side. From Nowa Kachowka, the lower reaches of the Dnipro follow a plateau. On the Ukrainian side, a pronounced steep bank stretches almost to the mouth. Downtown Cherson is on a ridge.
The tidal wave particularly endangered the settlements on the left bank in the Russian-controlled areas on the Dnipro. Here the shore is flat, the hinterland is swampy in places. More than a dozen settlements are located here at the beginning of the flat plains of the southern Ukrainian steppe regions.
(Photo: Map data: © OpenStreetMap contributors, SRTM | Map rendering: © OpenTopoMap (CC BY-SA 3.0))
However, the numerous river islands and the low-lying areas at the confluences of the tributaries are particularly threatened by flooding. Data from NASA’s earth observation service MODIS allows an initial assessment of the extent of the areas immediately affected just a few hours after the disaster.
By the afternoon of June 6, the water masses of the reservoir had mainly flooded the areas near the bank on the left, southern Dnipro bank. However, the NASA evaluation only provides approximate values: the data is based on an automatic analysis of optical sensor data. The extent of reflecting water surfaces is displayed.
Where the tidal wave washes over wooded areas, the Nasa data show nothing. This also applies, for example, to the mostly tree-covered river islands in the Dnipro Delta, where the river pours into the Black Sea around 90 kilometers below the Kakhovka Dam southwest of Cherson.
Note: The Kachowka Reservoir water level infographic will be updated as new data becomes available.
Data on the water level in the Kachowka reservoir suggest that the water level rose unusually sharply in the spring. The assumption is that the regulation of the flood gates at the dam was affected by the war. After a low in January, the level reached historic highs.
The information on the water level is based on measurement data from orbit: researchers from a European earth observation network keep an eye on the levels of important bodies of water here using satellites and radar signals. According to this data, the water level in the reservoir was recently just under 18 meters – and thus a good two meters above the long-term average.
Low water in winter, peak before the dam burst:
According to the Ukrainian government, up to 80 towns are at risk of flooding as a result of the destruction of the Kakhovka dam. Moscow and Kiev accuse each other of having blown up the Kakhovka dam.
The dam and adjacent facilities have come under fire several times in recent months. From the Ukrainian side, for example, the road connections on the south-eastern side were deliberately destroyed. In November last year, a heavy explosion shook the dam on the north-western side during the course of the Russian withdrawal from the Kherson region.
So far, however, experts are not assuming that the dam breach could have been triggered by the war damage that is already known. The evidence and interests suggest that Russia is behind the destruction, explained military expert Thomas Wiegold.
Rather, the enormous damage indicated a targeted blast, said dam construction expert Arnd Hartlieb from the Technical University of Munich. “Something huge must have happened,” he said on ntv.