Assignment 5: water systems
When applying for example a culvert, it is important to think about the function and the shape of the culvert. The aim is to allow water to flow from A to B. This is often based on calculations. Below are a number of tasks relating to art works. The necessary theory can be found in the PowerPoint presentation (see Appendices).
Assignment 5.1: Culvert
What is the flow rate through a fully filled culvert with a diameter of 800 mm, at a water level drop of 2 cm?
Assignment 5.2: Weir
What is the flow rate over a weir with an
overflow width of 1.50 m?
The weir level is NAP +1.27 m and the crest height of the weir is NAP +1.15 m.
(NAP: acronym for Amsterdam Ordnance Datum -Dutch vertical water height reference system)
Assignment 5.3: Weir
What is the minimum overflow width of the weir?
Size of drainage area: 150 ha.
Regulating discharge: 1.33 l/s/ha.
Maximum height of overflow radius at regulated discharge: 26 cm.
Assignment 5.4: Watercourse
What is the flow rate, and the velocity of flow if a
watercourse has the following dimensions?
Width of watercourse: 1.50 m.
Water depth: 1.00 m.
Overhang: 4 cm over 1 km.
Situation: Lightly vegetated (Km value: 26).
Assignment 5.5: Water balance
Is there any seepage or run-off in the area concerned? Calculate how much in mm/per day.
Size of area: 80 ha.
Period: 1 year.
Precipitation: 925 mm.
Evaporation: 488 mm.
Measured inflow through inlet is: 300,000 m3.
Measured discharge by way of a weir: 1,000,000 m3
Both level and groundwater levels are the same at the beginning and end of the period.