HomeProductsFlow regulationAbout Mosbaek North America, Inc.Info & news

» Facts on procedures and quality

» The story of Mosbaek

» References

» Contact form

 Send a technical inquiry



Aalborggade, the city of Randers, Denmark


In central Randers the basements had frequently been flooded over a period of time.  These floodings were found to be due to insufficient capacity of the area's sewerage system.  Another consequence of this was frequent surcharging to the nearby receiving waters, Tyvdalen, from an overflow structure in Aalborg Street.  The area's sewerage system is a combined system and it contains a large number of low lying basements which are sensitive to high water levels in the system.  The city's consultants carried out a number of MOUSE simulations in order to analyse the problem.  On the basis of this, the consultant suggested improving the capacity of the main sewerage system in Aalborg Street -  a second pipeline parallel to the existing one should be laid.  The central section of the new pipe was suggested to be a 48" (ø1200) pipe detention basin.

The two flow regulators secured the optimal functioning of the pipe detention basin.  In choosing this solution the city achieved a considerable reduction in the frequency of basement floodings and surcharges to the receiving waters.

The consulting engineers were Carl Bro A/S


Randers Shopping Centre, Denmark

Randers Shopping Centre is constructed on former farm land and it has 1800 parking spaces, distributed over the Centre's 21 acres (~8.5 ha) of open spaces. 

2/3 of the stormwater run-off from the parking lot and approx. 3.2 acres (~1.3 ha) roof top run-off is conveyed to an existing 32" (ø800) combined sewerage pipe in the nearby Merkurvej (Mercury Street).  Although the parking lot is laid out using small concrete tiles and green areas, one would nevertheless expect a considerable amount of run-off from the parking lot.

The capacity of the Merkurvej pipe is 11800 GPM (~746 l/s). 9400 GPM (~589 l/s) are already used by existing catchments.  The run-off from the Centre is estimated to exceed 17500 GPM (~1100 l/s) on average every 10th year.  It was therefore necessary to control the storm water run-off from the Centre's parking lot.

The problem was solved in the following way:  Each of the two parking lot blocks had installed a subterranean detention basin (viz. 2200 ft3 (~220 m3) and 3800 ft3 (~380 m3).  A CY vortex regulator controls the run-off from each basin (capacity viz. 1950 GPM (123 l/s and370 GPM (~61 l/s).  Some extra storage volume is gained by allowing moderate flooding on terrain (on average once every 10th year).  The volume gained is viz. 4800 ft3 (~480 m3) and 8200 ft3 (~820 m3) (i.e. twice the basins' volumes!).

The consulting engineers were Abrahamsen & Nielsen A/S.


Flow control of the spring Maglekilden, Roskilde city, Denmark.


Maglekilden is a small subterranean spring which originates behind Roskilde Cathedral.  In former times its water was believed to possess healing powers.  It yields 160-320 GPM (~10-20 l/s).

Until recently, its water was simply lead to the sewerage system, and from there directly to Roskilde Harbour.  One day the city council's engineers had the idea of utilising the water for recreational purposes - the water should feed a small artificial stream which was to pass a purpose-constructed little pond in the nearby situated park, Byparken.  The stream was designed to convey 240 GPM (~15 l/s).  As a safeguard against floodings in the park - should the spring in periods yield more than 240 GPM (~15 l/s) - a flow regulator was fitted at the spring.  The regulator ensures that only 240 GPM (~15 l/s) are conveyed to the stream - the rest goes to the harbour.

The gardens were inaugurated in 1998 and give much pleasure to the city council, the park's visitors and many ducks.

Mosbaek North America, Inc. • 3525 Piedmont Road • 7 Piedmont Center • Atlanta GA 30305 • E-mail info@mosbaek.com