The Broad, amongst others in the region, has
been researched intensively for some time. It has
a water surface area of 72 ha and a water volume
of 804103 m3. It is a shallow Ž12-m water
depth., highly eutrophic lake that previously had
a major phosphorus supply via the sewage treatment
works that discharges into the River Ant.
The bottom of the Broad consists of a fine, organic
mud, overlying peat. Barton Broad itself lies
in the main valley of the River Ant, a shallow,
slow flowing, navigable river which forms the
principal inflow and outflow of the Broad ŽPhil-
lips, 1984.. During the winter, the lake is effectively
flushed, with a water residence time of
approximately ten days. During the summer, when
river discharge is reduced, water residence times
are thought to be 2030 days ŽPhillips and Ker-
rison, 1991..