The paper looks at the process of development of a reservoir pressure maintenance (RPM) system in the Srednebotuobinskoye oil-gas-condensate field of Rosneft Oil Company. The field is located in the Republic of Sakha (Yakutia). The region has a number of specific climatic and hydro-geological features setting certain requirements to selecting a source of water. An integrated approach is implemented in the Srednebotuobinskoye field to provide water required for the RPM system, which includes surface and subsoil water supply sources. Prospecting and exploration activities were undertaken to identify promising subsoil water sources. In the , Srednebotuobinskoye field two aquifers have a potential for being water sources: the Bordonsk series and the Meteger-Ichera series. The Bordonskaya water can be used for waterflooding purposes without any preliminary treatment. The Meteger-Ichera water contains hydrogen sulphide and therefore requires treatment prior to being used for reservoir pressure maintenance. Laboratory core studies were performed and helped establish the impacts on reservoir permeability if a mixture of surface and aquifer water is used. The outcome of the technical-economic assessment was in favor of the Bordonsk series. As a result, an integrated strategy for reservoir pressure maintenance was developed to minimize early water coning. It envisages a two-stage approach to converting wells to injection. At the first stage, when the main source of injection water is rivers and water intake wells (water viscosity is not exceeding 1.5 mPa⋅s), a nine-spot waterflooding system is used. At the second stage, with an increasing share in total injection volumes of produced water with a viscosity of 4 mPa⋅s, a single-line waterflooding system is used. The strategy for developing the reservoir pressure maintenance system proved its effectiveness. The transformation of the nine-spot into a single-line system helped restore reservoir pressure without causing early water coning, and formed the basis for a mutli-fold increase in production rates.
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