It is preferable to sail along the Southern edge of the ‘Bristol Deep’ shipping channel. If however passage is being made on the Northern side then the preferred place to cross is before or around Battery Point at Portishead after first making sure that any such crossing will not impede the passage of any ship restricted to the deep water channel. Avoid the area around King Roads which is used to swing large ships accessing Portbury or Avonmouth Docks. When the tide is in flood, the ships may need to turn through 180° to allow them to stem the tide. After passing Battery point stay South of the shipping channel. Cross the Portbury dock entrance close inshore after checking that there are no vessels entering or leaving the dock. Aim to pass the pier head at least 50mtrs off. Beware of ships and large Tugs which may leave the docks at any time.
When approaching from the North. Cross close in front of the Avonmouth (Royal Edward) dock staying well clear of the disused fuel pier on its North side. It is recommended that Bristol VTS be contacted (CH12) to ascertain any impending shipping movements.
The pilots and tug operators who take ships in and out of the docks are by necessity very skilled at their work. However a large ship is very restricted in its ability to manoeuvre especially when travelling at low speeds. If you are at all uncertain as to the intentions of a ship, keep well clear and contact Bristol VTS, who will be able to give helpful advice.
Entering the River Avon
At the entrance to the River watch your depth and keep North around the Swash Bank. Many boats have waited for a tide on the bank. It is soft mud which can give a poor return on an echo sounder.
The following speed restrictions operate in the River.
Vessel drawing 1.9m or more: 7 knots over the ground/6 knots through the water
Vessel drawing less than 1.9m: 9 knots over the ground/9 knots through the water
In addition, you are required to slow down past moorings (there may be people in a dinghy amongst the boats).
If upon arrival at Avonmouth you cannot get into the River Avon – either beause you’re too early or too late on the tide – then anchoring is possible inshore, between Portishead Dock and the Royal Portbury Dock entrance fairway. This anchorage is to be avoided during an onshore wind whence advice should be sought from Bristol VTS (Avonmouth Radio). Current navigational instructions for the River Avon state that vessels up to 99.0 metres in length, with a mast height of up to 27.0 metres are permitted to navigate to the City Docks without the need to obtain the Haven Master’s sanction.
Be aware of powerlines and the M5 motorway bridge, which restrict the air draft about a mile into the river.
When approaching the River Avon entrance inward bound, leave South Pier Lighthouse close to port.
Make an allowance for flood tide, running northeast across entrance at up to 4.5 knots at 3 hours to high water on spring tides.
On entering the river and on departure, keep to the North Bank. Do not attempt to cross the Swash Bank.
On departure keep the St. George’s transit astern then north of the line of the Swash leading lights until abeam of the South Pier Lighthouse.