Slough Sewage Farm - more info
SSF has changed enormously over the recent past. The building of the Flood Relief Channel (Jubilee River) has meant that much of the "rough ground" and old beds have gone. Old Berkshire reports are filled with great birds at SSF .. those days are gone ;o)
The JRR has meant greater viewing opportunities for the ordinary birder. Walking along the north bank of the Jubilee river gives good views into the site. A must if you visit JRR.
The waders are usually on the top (sludge) beds - beds 1, 2 & 3 on the map but can be found around the edges of bottom bed 4. In 2003 bed 5, which had been "full" of water has been left to dry-out and lots of vegetation has grown-up. Pipits, wagtails, snipe and sandpipers have all used this bed. The green-winged teal in Feb '04 was originally located on this bed before showing well on Jubilee river the next day. Both view points [Dorney & the M4 footbridge] allow relatively distant views though, if the waders are on beds 1 or 4 the M4 can give good views [and within the range of digiscoping, if so inclined]
grey wags can be seen in the clinker beds [only viewable from Dorney
wetlands - either the closer north bank or, with a higher vantage point,
the south bank]. Further along Roundmoor ditch there is a small
"shore" which can have wintering water rail. Just before the
weir on Jubilee river there are views over rough grassland towards filter beds.
Although it's not possible to see anything of the beds the isolated trees
are worth a second look, especially during migration. There are loads of
reed/sedge warblers along the ditch. You'll have to return this way as
there is no way to make a round trip of it as there is a locked gate at
the end of the north bank.