Daylighting is the opening up and restoration of a previously buried watercourse, one which had at some point been diverted below ground. Typically, the rationale behind returning the riparian environment of a stream, wash, or river to a more natural above-ground state is to reduce runoff, create habitat for species in need of it, or improve an area's aesthetics. In the United Kingdom, the practice is also known as deculverting.

The Porter Brook is a river which flows through the City of Sheffield, England, descending over 1,000 feet (300 m) from its source on Burbage Moor to the west of the city to its mouth where it joins the River Sheaf in a culvert beneath Sheffield railway station. Like the other rivers in Sheffield, its steep gradient made it ideal for powering water mills and works associated with the metalworking and cutlery industries, and around 20 dams were constructed over the centuries to facilitate this. At its lower end, it is extensively culverted, but parts of it are gradually being restored to open channels, as part of a daylighting scheme for the city.