орчны урсац хуримтлуулах хиймэл усан сан
detention basin
водохранилище местного стока
Detention basins are normally dry, but are designed to detain surface water temporarily during, and immediately after a runoff event. Their primary function is to attenuate the storm flows by releasing flows at a lower flow rate. There are no gates or valves allowed on the outlet so that water can never be stored on a long-term basis. Typical detention times in such a basin would be on the order of 24 to 72 hours although some are as long as 5 to 10 days.
Source http://www.nws.noaa.gov/om/hod/SHManual/SHMan014_glossary.htmЗураг