River Gade

It rises from a spring in the chalk of the Chiltern Hills at Dagnall, Buckinghamshire[1] and flows through Hemel Hempstead, Kings Langley, then along the west side of Watford through Cassiobury Park.

After passing Croxley Green it reaches Rickmansworth, where it joins the River Colne.

Its principal tributary is the River Bulbourne which joins it at Two Waters, just below Hemel Hempstead.

Below Hemel Hempstead it runs alongside and sometimes forms part of the Grand Union Canal.

The river bed from the source at Dagnall to Great Gaddesden, about 3 miles downstream is usually dry.