As cities expand, urban planning and efficient land use becomes more important and presents new challenges. A city that is exposed to these challenges is Stockholm, Sweden (Stockholms stad, 2018). The expansion of the city can lead to expensive acquisition of land above ground, which therefore results in an increase of subsurface infrastructure being constructed. The construction below ground level also imposes challenges affecting our urban environments above ground. One of the challenges when working below ground level is the management of groundwater. The groundwater exists in filled pores of soil and rock below the groundwater table and can potentially leak to a subsurface construction. However, redirecting the groundwater requires permission from the environmental court (SGU, 2017). The purpose of this thesis is to examine how well a hydrogeological prognosis corresponds to the outcome of a specific infrastructure project; the contract Hjulsta Norra in the Stockholm Bypass. More specifically, the thesis has been divided in four different objectives relating to the main purpose. The thesis has been conducted through literature studies of reports and studies within relevant subjects as well as specific data analysis for the case of Hjulsta Norra. The literature studies attempt to explain how hydrogeology relates to infrastructure, the building process, environmental legislation and the hydrogeological prognoses purpose. The case study is conducted for a part of the Stockholm Bypass that is developed by NCC; Hjulsta Norra. The Stockholm Bypass project is developed to increase accessibility around the Stockholm region (Trafikverket, 2020a). The contract consists of the construction of a tray and two concrete tunnels (NCC Infrastructure, 2017a) and the building process is divided into several stages (Montelius, 2020). Geologically, the area of the contract Hjulsta Norra is varied but mainly consists of gneiss or granite overlaid by friction soil and sometimes clay. The friction soil layer is partially below the ...