sentences:  The Kacha approaches Krasnoyarsk from the north and goes straight through the city, joining the Yenisey in the historical center of the city, Strelka.Kacha has been long known for being the most polluted river of the Krasnoyarsk area, and only in the middle of the 2000s was the situation improved, at least in the Krasnoyarsk section of the river.The most serious pollution sources were several unfiltered sewage pipes and numerous solid wastes on the river banks.