Castor Backwater and Main River

River level

The lowdown

• This is proper open-water fishing, with several alternative areas rather than a peg-by-peg sort of venue. Handy if you fancy a wander and a bit of searching.
• The Castor Backwater runs from the weir to Water Newton Lock. It holds silverfish and bream, with the bream particularly worth thinking about through the warmer months.
• Predators follow the silverfish and bream stocks, so there’s clearly plenty going on beneath the surface. The facts don’t name the predator species, though.
• Winter is chub time. You may need to rove about to locate them, with the spinney described as prime chub territory and overhanging trees providing cracking cover.
• Downstream, the scene changes from open field to another wooded section. Keep an eye out for the concrete post, which marks the point beyond which the land is private.
• P&D AA water resumes after the boat-mooring area downstream of the lock. Upstream of the bridge, the left bank has prime barbel swims.
• The main river holds barbel, specimen chub and roach, with a short backwater section before it joins the river. The fishery continues for one meadow before Splash Lane Meadows Fishery.
• Access is from the bottom of Station Road, Ailsworth. Park roadside, cross the Nene Valley Railway through the pedestrian gate, then use the green metal entrance gate.
• After the gate, the backwater is a few hundred yards ahead. Fish either bank upstream of the access point; after crossing the bridge, the right bank runs to the confluence and onwards to the mill pool below the lock.
• Livestock can graze the meadows, and public paths and bridleways cross or follow some banks, so keep gear tidy and give people and animals room.

Methods: Warm months look suited to bream and silverfish work, while winter calls for a mobile chub approach around the spinney and overhanging trees. On the main river, target the left-bank barbel swims upstream of the bridge and explore the glides and cover rather than sitting tight all day.

Access & tickets

Day tickets are available online through Peterborough & District Angling Association. The 2026 adult advance ticket is £5, senior is £3 for anglers aged 65 and over, and juniors under 18 are free; booking on the day adds a £2 surcharge. Annual night permits need to be arranged by contacting the association directly.

Fish the club names

barbel, chub, bream, roach

Key rules

• A valid Environment Agency rod licence is required.
• River fishing is closed from 15 March to 15 June inclusive.
• No night fishing is permitted on P&DAA waters.
• Fishing is normally allowed from one hour before sunrise to one hour after sunset.
• Livestock may graze the meadows, so anglers must take care around animals.
• Public paths and bridleways crossing or following P&D AA banks must not be obstructed.
• Do not go beyond the concrete post, as the land beyond it is private.
• Tickets are non-transferable and non-refundable.

Where it is