Vodokanal Experts Name Main Reasons for Flooding During Cloudbursts and Identifies “Vulnerable” Areas of St.Petersburg


Specialists of SUE “Vodokanal of St.Petersburg”, within the framework of the RAINMAN Russian-Finnish project on urban drainage system adaptation to the rains intensity increase, have identified the territories that have the greatest risk of flooding.

93% of the historical built-up areas and 50% of the existing residential areas are covered with asphalt, roofs and other surfaces with low permeability, which enables a high load of surface runoff on the existing networks.

These areas are facing a risk of flooding under the climate change conditions in case of off-nominal “tropical” showers. At the same time, the flooding challenge can be aggravated by household wastes in stormwater inlets.

Moreover, it is often nearly impossible to update drainage systems in the historical center of St.Petersburg as historical monuments are protected by the state and it is prohibited to carry out excavation in the immediate vicinity of the historical buildings foundations.

The Company persistently carries out preventive measures, and operational activities during off-nominal precipitation periods to ensure uninterrupted drainage of surface runoff from urban areas.

On May 24-25, Moscow hosted the XII “Ecology” International Forum, which addressed main environmental trends of the new decade, aimed, in particular, at curbing global warming and shaping eco-awareness. Vodokanal’s specialists reported on international cooperation in the development of water supply and wastewater disposal systems, including wastewater disposal systems operation simulation in the areas most prone to flooding during cloudbursts, taking into account future climate change and prospects for the St. Petersburg development.

Vladimir Gvozdev, Deputy Director of the Department for Water Supply and Wastewater Disposal Systems Analysis and Technological Development, described thematic priorities of the Russian-Finnish project “Towards higher adaptive capacity in urban water management” (RAINMAN).

Today, the estimated rainfall rate in wastewater disposal systems designing is determined based on data that does not account current and future climate change scenarios. In this regard, a need arises to develop a regional methodological document with updated climatic parameters and an adapted calculation methodology.

An increase in the intensity of rainfall associated with climate warming is an urgent challenge not only for St.Petersburg, but also for other cities in the world. This grounds Vodokanal’s participation in the RAINMAN project, which results will allow the participating cities (St.Petersburg, Helsinki, Lahti, Mikkeli and others) to incorporate adaptation measures for the urban environment development to their strategies, which will ultimately ensure a favorable quality of life for future generations.

The participants of the international project will collect information and achievements on the considered topics and prepare recommendations that will form the basis of the document for all stakeholders involved in the urban territories development. An important recommendation is a possible decrease in the runoff rate by increasing a share of permeable areas and green spaces.

Vodokanal continues to cooperate with foreign partners in various areas of water service, as it was unveiled at the Forum by Dmitry Troshenko, the Company manager for organizational support and protocol. In his report, he paid special attention to such international projects as the Southwest Wastewater Treatment Plant construction, the Northern Tunnel Collector, wastewater sludge incineration technology implementation, as well as the International Advanced Water Technologies Center activities.