Most of the streams in the park drain into Beverley Brook but a spring above Dann's Pond flows to join Sudbrook (from "South brook") on the park boundary. Sudbrook flows through a small valley known as Ham Dip and has been dammed and enlarged in two places to form Ham Dip Pond and Ham Gate Pond, first mapped in 1861 and 1754 respectively. These were created for the watering of deer. Both ponds underwent restoration work including de-silting, which was completed in 2013. Sudbrook drains the western escarpment of the hill that, to the east, forms part of the catchment of Beverley Brook and, to the south, the Hogsmill River. Sudbrook is joined by the Latchmere Stream just beyond Ham Gate Pond. Sudbrook then flows into Sudbrook Park, Petersham. Another stream rises north of Sidmouth Wood and goes through Conduit Wood towards the park boundary near Bog Gate.