Comprehensive redesign of the drainage concept for the city of Mragowo using retention, infiltration and Green-Blue infrastructure

The PANDa precipitation model for Mrągowo was used for the current state and 2050 conditions, taking into account climate change. Based on the hydrodynamic model created, the project “Construction and reconstruction of the main rainwater collectors in the area of the City of Mragowo” was revised. Revision of the project included:  determination of design rains and hydrological conditions, verification of catchment operating conditions for different rainfall scenarios in the existing and future state, design solutions that are the subject of the project amendment, together with a valuation of the capital expenditure, description of Green-Blue infrastructure activities and guidelines, jak również the provisions of the Information Sheet of the Project  and calculations for water rights operations. 



  • An amendment to the water law has made it possible to use rainwater and counteract the effects of drought by recharging the drying up Sołtyskie Lake, instead of discharging rainwater through large-diameter collectors outside the city center area. How to avoid the construction of an expensive interceptor, reduce capital expenditures with the redirection of the obtained savings to increase the share of Green-Blue infrastructure and local infiltration solutions? 


  • The Municipality of Mragowo commissioned RetencjaPL experts to prepare a technical opinion on a possible change in the technical solution to the shortfalls of the water management system in Mragowo, which would result in a request for a change in the scope of the grant agreement. As a result of the analysis of a number of scenarios on the hydrodynamic model created, an amendment to the project documentation was prepared. 


  • Model project with a number of synergistic benefits and use of the Soltyskie, Mazurskie and Juno lake complex:
  • Investment savings and easier construction work, with a reduction in the troublesome section of the interceptor on non-bearing soils.
  • Increased retention, new reservoirs,
  • Using rainwater for a rainy playground.
  • Green-Blue infrastructure and biodiversity growth, hydrophytic treatment.
  • Proper sizing of collectors and the system – reducing flooding.
  • And much more….