River Mole Brook, Gatwick Stream, Earlswood Brook, Pipp Brook and The Rye, which drains Ashtead. A full list of the tributaries is given in the table below. River Mole The River Mole is a tributary of the River Thames in southern England. It rises in West Sussex near Horsham and flows northwest through Surrey for to the Thames at East Molesey, opposite Hampton Court Palace. The river gives its name to the Surrey district of Mole Valley. The Mole crosses the North Downs between Dorking and Leatherhead, where it cuts a steep-sided valley, known as the Mole Gap, through the chalk. Much
De Hiemerter Mole, Burgwerd diesel engine was removed in the mid-1970s and an automatic pumping station built. In 1973, the mill was bought by De Hollandsche Molen. In 1976, the mill was restored to working order. On 16 May 1988, the mill was sold to Stichting De Fryske Mole (English:"Frisian Mills Foundation"). "De Heimerter Mole" is what the Dutch describe as a "spinnenkopmolen" (English: "Spider mill"). It is a small hollow post mill winded by a winch. The four Common sails, which have a span of , are carried in a wooden "windshaft". The "windshaft" also carries the "brake wheel" which has 29 cogs.