Summary
Sea Mills is a classic upper-estuary mark on the tidal River Avon in northwest Bristol, where the River Trym joins the Avon en route to the Severn. The huge tide, swirling eddies and coloured water make it a dependable, urban-access venue for flounder, school bass and mullet.
Location and Access
Getting to Sea Mills is straightforward and mostly flat, with several short walks from parking to the bank. Most anglers fish near the small historic harbour (the Trym outfall) and along the riverside path towards Shirehampton.
- Access via the A4 Portway; turn into Sea Mills for the station/Sea Mills Square, then walk to the river in a few minutes.
- Public transport: Sea Mills railway station (Severn Beach Line) is a short walk from the bank; frequent buses run along the Portway.
- Parking: limited on-street around Sea Mills Square and a small station car park; observe local restrictions and never block the slipway.
- Walk and terrain: mostly level tarmac/shared-use path with grassed verges and some firm concrete by the harbour; banks can be steep and slippery.
- Where to set up: firm ground by railings near the harbour, and selected pegs along the path where the bank is stable and not undercut.
Seasons
The mark fishes like an estuary river: coloured water, crabs, and seasonal run-ins. Expect reliable flounder, schoolie bass in season, and mullet around the slack water windows.
- Spring (Mar–May): flounder; school bass appearing on warmer tides; thick‑lipped mullet show late spring; the odd silver eel at dusk.
- Summer (Jun–Aug): bass (mostly schoolies with the odd better fish); thick‑ and thin‑lipped mullet in the harbour/eddies; steady flounder.
- Autumn (Sep–Nov): prime time for estuary bass on crab and worm; consistent flounder; occasional codling and whiting can push upriver in cold snaps on big springs.
- Winter (Dec–Feb): flounder remain the mainstay on neaps; a chance of an upriver codling in prolonged cold; eels largely absent.
Methods
Fast currents favour streamlined rigs, breakout leads and scent-heavy baits. Mullet reward stealth and fine tackle during the gentler tide windows.
- Bottom fishing: 5–7 oz breakout grip leads; clipped-down pulley or up‑and‑over for bass/codling; 2‑hook flappers (size 1–2) for flounder.
- Baits: peeler crab is king (especially Apr–Jul and late summer); blow/black lug and ragworm; mussel and razor; squid or mackerel strip as a cocktail at night.
- Attractor tweaks: small beads or spoons for flounder; keep snoods 60–90 cm on neaps, shorter on big springs to reduce twist.
- Mullet tactics: bread flake/crust under a float or small ragworm; size 6–10 fine‑wire hooks; loose‑feed bread mash sparingly near the Trym outflow/harbour walls.
- Lures for bass: 3–5 inch paddle tails or slim shads in dark/silhouette colours on 10–20 g heads; work current seams and eddies on the flood.
- Best windows: 2 hours before high water to 1 hour after; dusk into dark often lifts bass/codling prospects.
Tides and Conditions
The Severn’s range is felt strongly here. Plan around manageable flows and avoid the fiercest springs unless you’re geared for it.
- Tide reference: use Avonmouth tide times; streams are very strong on the mid-river bends and at the Trym confluence.
- Productive states: mid to top of the flood and the first of the ebb; neaps or mid-range springs for better presentation and holding bottom.
- Springs vs neaps: big springs can demand 7–8 oz grips and still roll; neaps allow lighter leads and flounder “trundling.”
- Freshwater effect: after heavy rain, salinity drops and bass sport can dip—flounder tolerate it better; give it 24–48 hours after spates.
- Light and wind: coloured water means daylight can fish fine, but dusk/dark is best for larger fish; winds funnel along the valley—shelter varies by bend.
Safety
This is a powerful, silty estuary with rapidly rising water and treacherous mud—treat it with utmost respect.
- Never step onto exposed mud or clay; people and dogs have become stuck—keep to firm ground and the path.
- Beware undercut banks and slippery grass; stay back from the edge at high water.
- Some pegs flood or become cut off on big highs—especially near the Trym—know your exit points.
- Expect floating debris (logs) on springs; keep lines high and be ready to wind down.
- Use a lifejacket, headtorch and grippy footwear; a long-handled drop net helps safe landing.
- Shared path: keep tripods and rods clear of cyclists/runners; avoid casting across the path.
- Accessibility: step‑free, mostly level access from the station/Sea Mills Square; firm, flat spots by the harbour suit many, but sloped banks elsewhere may not suit wheelchairs.
Facilities
Urban convenience is good, but there are no angler‑specific facilities at the water’s edge.
- Transport: Sea Mills railway station is a short walk; buses run along the Portway.
- Parking: limited on-street and a small station car park; respect residents and the slipway.
- Amenities: cafés/shops around Sea Mills Square (variable hours); no dedicated public toilets on the bank—plan ahead.
- Tackle/bait: several Bristol tackle shops carry sea bait (lug, rag, squid, occasional crab); call ahead to reserve fresh crab or lug.
- Connectivity: generally good mobile signal; minimal lighting away from the station area—bring a headlamp.
Tips
Local knowledge goes a long way at Sea Mills—small tweaks can transform a session.
- Use a weak‑link/rotten‑bottom below your lead to save gear around snags and tree roots.
- Slightly splay two grip wires so they release on steady pressure during the retrieve.
- Bait elastic is essential for soft baits (crab/mussel) in fast tide; keep baits compact and streamlined.
- For flounder on neaps, try a slow‑rolling plain lead with a size 1 hook, beads and a short snood—cover ground across the channel.
- Pre‑bait delicately with bread mash for mullet; keep noise to a minimum and lines light (6–8 lb, small floats).
- Don’t overcast: many bass patrol tight to the bank at dusk; 20–30 yards is often enough.
- After prolonged rain, try slightly downstream towards Shirehampton for better salinity and bass chances; in summer, fish the first of the ebb when crabs settle.
Regulations
This is tidal water. Sea angling is generally permitted from the public bank, but you must follow national and local rules—always check the latest official guidance before you go.
- Rod licence: no Environment Agency licence is required to fish for sea species in tidal waters. Targeting salmon or sea trout requires the appropriate EA migratory fish licence and permissions; seasons and strict rules apply.
- Bass: recreational bass rules change frequently. In recent years, a 42 cm minimum size has applied, with catch‑and‑release only in Jan–Feb and Dec and a small daily retention limit in Mar–Nov. Check current MMO/Defra notices before keeping any bass.
- European eel: critically endangered—do not target. Any eel caught must be released immediately in England.
- Protected species: allis/twaite shad and any accidentally caught salmon/sea trout must be returned immediately. Do not deliberately target them in this area.
- Nursery areas: parts of the wider Severn Estuary are designated bass nursery areas with extra restrictions (especially for fishing from boats and retaining bass). Check the latest nursery maps if fishing by boat or retaining fish.
- Local access: obey any on‑site signage (e.g., no fishing from private moorings, the slipway, or railway property). Keep clear of launching craft and do not obstruct the slipway.
- Size/bag limits: observe current recreational size and bag guidance where applicable, and consider voluntary release of large breeding fish.
