They wereprimarily meant to break the ice and prevent troops and heavy military equipment from crossing the Volga river andIvankovo Reservoir.This began with the blowing up of the Istra(ru)waterworks reservoir dam on 24 November 1941.On 28 November 1941, the water was drained into the Yakhroma and Sestra Rivers from six reservoirs (Khimki(ru),Iksha(ru), Pyalovskoye(ru), Pestovskoye(ru), Pirogovskoye(ru), and Klyazma(ru)reservoirs), as well as from Ivankovo
The Soviet winter counter-offensive, 5 December 1941 – 7May 1942A Soviet machine gunner coversattacking infantry near Tula, inNovember 1941.Reservoir using dams near Dubna.This caused some 30-40 villages to become partially submerged even in thesevere winter weather conditions of the time.Both were results of Soviet General Headquarters' Order 0428dated 17 November 1941. Artificial floods were also used as unconventional weapon of direct impact.Soviet counteroffensiveAlthough the Wehrmacht's offensive had been stopped,German intelligence estimated that Soviet forces had nomore reserves left and thus would be unable to stage acounteroffensive. This estimate proved wrong, as Stalintransferred over 18 divisions, 1,700 tanks, and over 1,500aircraft from Siberia and the Far East.The Red Armyhad accumulated a 58-division reserve by earlyDecember,when the offensive proposed by Zhukovand Vasilevsky was finally approved by Stalin.Evenwith these new reserves, Soviet forces committed to theoperation numbered only 1,100,000 men,only slightlyoutnumbering the Wehrmacht. Nevertheless, with carefultroop deployment, a ratio of two-to-one was reached atsome critical points.On 5 December 1941, the counteroffensive for "removingthe immediate threat to Moscow" started on the KalininFront. The South-Western Front and Western Fronts began their offensives the next day. After several days of littleprogress, Soviet armies retook Solnechnogorsk on 12 December and Klin on 15 December. Guderian's army "beat ahasty retreat towards Venev" and then Sukhinichi. "The threat overhanging Tula was removed.":44–46,48–51On 8 December, Hitler had signed his directive No.39, ordering the Wehrmacht to assume a defensive stance on thewhole front. German troops were unable to organize a solid defense at their present locations and were forced to pullback to consolidate their lines. Guderian wrote that discussions with Hans Schmidt and Wolfram von Richthofen tookplace the same day, and both commanders agreed that the current front line could not be held.On 14 December,Franz Halder and Günther von Kluge finally gave permission for a limited withdrawal to the west of the Oka river,without Hitler's approval.On 20 December, during a meeting with German senior officers, Hitler cancelled thewithdrawal and ordered his soldiers to defend every patch of ground, "digging trenches with howitzer shells ifneeded."Guderian protested, pointing out that losses from cold were actually greater than combat losses and thatwinter equipment was held by traffic ties in Poland.