Yauza waterway lock, Waterway lock in Lefortovo District, Russia.

The Syromyatnichesky (Yauza) hydroelectric complex stands on the Yauza River, three kilometres from its mouth, between the Zolotorozhskaya and Academician Tupolev embankments. It comprises a single-chamber, single-line lock on the left bank and a 20-metre-long spillway dam on the right bank, separated by a small artificial island with trees and hydraulic structures. The lock raises and lowers vessels by 4 metres.

Built in 1940 to a design by architect G. P. Golts (1893–1946), the Syromyatnichesky hydroelectric complex was the only one of four planned navigable locks on the Yauza to be realised under Moscow's 1935 General Plan. It replaced the Zolotorozhsky Bridge, demolished before construction, and takes its name from the nearby Syromyatnaya sloboda. A major overhaul followed in 2005–2006.

The name comes from the Syromyatnaya sloboda, a settlement that once stood nearby. The complex is a regional cultural heritage site, and its sluice chamber is equipped with traffic lights; a "bridge clearance" sign of 6.0 m stands on the upper head. Mooring bollards in the upper pool sit in recesses built into the embankment railing.

You can watch the lock operate from viewing areas along the embankment, especially when boats pass through. The best views are from the waterfront promenade where you can see how the gates and water levels work together.

The lock maintains precise water level controls through a dual-gate mechanism that allows vessels to transition between varying river elevations.