Foudry Brook rises at springs between the small villages of
Heath End and
Baughurst, where it is known as Bishop's Wood Stream. It flows eastwards though
Tadley, and is briefly culverted under housing on Elmhurst before emerging back on the surface and passing under the A340 Mulfords Hill road. It then enters a much longer culvert under Tadley Bottom, and emerges into open countryside on the east side of Bowmonts Bridge. It crosses the Pamber Forest nature reserve, becoming the Silchester Brook, and turns to the south, where Silchester Sewage Treatment Works is on the right bank. It then passes between two earthworks before Honeymill Brook joins it on the right bank. The linear earthworks were associated with a Late Iron Age town that developed into the Roman town called
Calleva or
Silchester. They are and long, with a gap of where the river passes through. Honeymill Brook rises at a pond near Browninghill Green, to the south of Baughurst, and at a series of springs to the east of the village near Church Brook Farm. The two sources join near Church Road, Tadley and flow eastwards to Honey Mill Bridge, which carries the A340 Aldermaston Road over the brook. The course of the
Port Way Roman road also crosses at this point on the western boundary of Pamber Forest. On the far side of the woodland, it runs parallel to the earthworks and joins Silchester Brook as it turns to the east again. At Park Copse, higher ground prevents further progress to the east, and as turns to the north, The outflow from the moat joins Silchester Brook at Clapper's Farm. The
Reading to Basingstoke railway follows the valley northwards, running alongside the river. On the right bank opposite the church building is a long linear fishpond. The river drops over a waterfall, which was originally part of a hydraulic ram, and provided water from the river to Manor House. This was also the location of a medieval watermill, and the straight course of the river below the waterfall may be due to the fact that it was built to return water from the mill to the river. A mill was recorded in the manor of Stratfield Mortimer when the
Domesday Book was compiled in 1086, and there is documentary evidence for a mill in 1304 and again in 1449–50, but nothing subsequently. Tun Bridge carries Station Road to the nearby
grade II* listed Mortimer railway station, built by
Isambard Kingdom Brunel in 1848, and notable because it is one of a small number of his wayside station buildings that have remained virtually unaltered since their construction. After passing Stratfield Mortimer Sewage Treatment Works on its left bank, the river turns to the east near Wokefield Park Training Centre, passing under the railway line, which continues northwards. Missels Bridge carries Cross Lane over the river before it passes another Clappers Farm, this one with a farmhouse dating from the 16th century with 19th century alterations. Reid's Bridge carries the drive for Brook Farm, after which a ridge of higher ground separates the valley from that of the
River Loddon, and so the river turns to the north. The hamlet of Lambwoodhill Common is on the left bank, with Foudry Bridge to the south and Gravelly Bridge to the north. Just before it reaches the
M4 motorway Burghfield Brook joins on its left bank, and after the bridge, the stream passes between the
Green Park Business Park and the
Madejski Stadium and football centre west of
Whitley, where it provides the water for the meadow-landscaped lakes. It then passes under a large roundabout on the
A33 road, carries on between
Thames Water's Reading sewage treatment works to the west and the Brunel Retail Park to the east, before discharging into the
River Kennet, here canalised as part of the
Kennet and Avon Canal, just downstream of Fobney Lock and Bridge 8A, which carries the A33 over the Kennet. The Kennet weaves its way through
Reading passing through County Lock and Blake's Lock to join the
River Thames downstream of
Caversham Lock. ==Geology and hydrogeology==