Responses
Since St Petersburg's very beginnings, flood prevention has always been a topic that was high on parliament's list of to-do's. A decree brought forward in 1721 read, "The moment when water starts coming up, all people and livestock are to be removed further into the woods," while not the most well thought out plan of evacuation, what the people of St Petersburg did was something that had never been done before as prevention was not a commonly known procedure, rather curing. Empress Catherine I issued a decree which requires marking the water level at it's high point after a flood and building St Petersburg's dam 1 foot higher than this measurement and Empress Catherine II the Great had water canals built to help cope with heavy water flow. Cannon fire, drums and church bells were used to warn the general public of a flood and red flags were flown on spires along with lit lanterns to signify a flood closing in. Most of the floods that occurred in St Petersburg occurred in November or December, the coldest and wettest months. Casualties were higher than they should be and many deaths were preventable as many people living in St Petersburg had never heard of, let alone seen a flood, so when flood warnings were put in place, people would flock to the Neva river and other coastal areas to watch the banks overflow, unaware of the dangers in doing this. No media articles were printed until almost 50 years after the 1824 flood and the cleanup process altogether cost in today's money, 30 million dollars.
Future Preparation
After over 270 floods, the St Petersburg government began a project in 1998 to stop flooding once and for all. They built the equivalent of 11 dams that spanned 25.4km with a width of 30m and a height of 8m. The St Petersburg dam has 2 navigation channels for boat traffic that are around 16m deep and can prevent flood waters up to 5.4m. The dam cost $3.85 billion dollars all up and includes a six-lane highway, 6 discharge sluices, 2 moveable floodgates and a new major traffic tunnel. It sits near the coast around 4m above sea level but, surprisingly has been a project idea since 1727 and was only commissioned on August 11 2011. Some of the reasons that floods occur in St Petersburg are less preventable and predictable than others, such as the fact that St Petersburg is situated on a low-lying floodplain where rain and a period known as the melt often coincide, the warmer rain causing the cold ice to melt, causing flooding. The ice can also be melted after brief warm weather periods known as El Nino's that can melt the ice. Global warming is one of the reason that conditions such as these are possible and sometime heavy ice sheets can even cause areas of land to sink. Building dykes, levees, seawalls and flood gates are all strategies used to reduce the impact of flooding and vegetation's roots can hold soil together and soak up extra water. these factors, along with having permeable and porous ground can soak up water and reduce the amount of flooding that occurs.