It's hard to say, because flooding in Russia happens regularly in different places, and without a specific news date, it's unclear which event you're talking about. Over the past few years, serious floods have occurred in Amur Oblast, the Far East, and Krasnodar Krai - these are different regions with different causes. If you saw a recent news story, check the date and source to pin down the specific city.
As for general preparedness: if you live in a region where flood risk is real, it makes sense to find out in advance whether your house is in a flood zone (this information is available at local administrations or the Ministry of Emergency Situations), subscribe to alerts from the regional Ministry of Emergency Situations, and keep your documents and important things in one place so you can grab them quickly. By the way, those who live in private houses close to rivers or in low-lying areas are advised not to store anything expensive or critical on the lower floors.
If this happened recently in your region, it's worth tracking the recommendations from your local Ministry of Emergency Situations - they give practical advice based on local conditions. Just keep in mind that one news story about flooding doesn't mean it'll happen every year, but preparing in advance is still worthwhile.