Monthly river flow rates for Russia and former Soviet Union countries in ds553.1 are augmented with data from Russia's State Hydrological Institute (SHI) and a few sites from the Global Hydroclimatic Data Network (GHCDN) . This compendium (v1.1 September 2001) includes 2458 gauges spanning all major river and oceanographic basins of the entire former Soviet Union. Exact dates vary by station. See the inventories for detailed information. Records are generally long: mean length is 36.3 yrs and 1,724 (70%) gauges have 25 or more years of data. 1,373 gauges have data to 1985 and another 909 gauges also have some data from 1986-1995. 640 gauges represent watersheds of 10,000 or more sq km, and 1,055 gauges represent catchments of 1,000-9,999 sq km. The SHI additions have not been scrutinized as rigorously as ds553.1.