The first station opened in 1867 and the second station opened in 1954.   If there's the same gap again, the third station will open in 2041.

The first mention on this forum of plans to re-open Portishead were described in 2007 and it's now 2024.  If we're half way through the process now (are we?), it will be another 18 years - so that also points to 2041.

Do members think it is realistic to have passenger trains to Portishead again by 2041?

 

Blinkin' flip!  I checked out Avonmouth docks on "Know Your Place" to look at an old map overlay and I see what you mean.  It's marked as Dumball Island and is now within the docks boundary.  I had no idea about this...most interesting, thanks.
I'm guessing the similarity in name to Dunball Wharf near Bridgwater is just coincidence.

 

No. It became Dunball Island, still in the Avon delta, then the old main (northern) channel was replaced by the port works downstream of Royal Edward Dock and the entrance lock and graving dock are where Dunball Island was. And there were three more short-lived stations there - one by that entrance lock, and the Pier Station (now the cruise terminal, roughly) and the GWR Docks Station - not to be confused with the joint GWR & MR Docks Station where the current one is!

And the basin by Portishead Mill, no longer tidal by 1880 as it was upstream of the dock which had sea gates, was where the 1954 station was put (though it was filled in much earlier).

 

Could that be Dunball with it's wharf on the river Parrett just above Bridgwater?  It was in commercial use up to recently (perhaps still is?) and I've been able to glimpse sea going vessels moored there on occasion while passing by on the M5 nearby.

 
I note the vaguely amusing name Dung Ball roughly where Avonmouth Docks now are.

 

A tidal creek is what I was thinking of. There is an 1810 map - before the port and the Methodist church were built - showing that (Portubury Ditch, I think) to the east and a leat from it to the mill. Portishead was then all to the south, though the High Street did lead onwards beside the mill branch of the creek. After the port was dug out there was a basin below the mill, but no sign of any quay - so presumably limited to small boats pulled onto the (mud) bank. And as to tying them to the church ... not popular with traffic along the High Street, e.g. to the port, I think!

 
And yet as recently as the 1880s the sea came up to the White lion pub now called the old mill by means of a tidal creek.Evidence for this can be found in the iron rings set into the wall of the Methodist  church  useful for tying boats up. The grinding millstone from the mill can be seen on the opposite side of the road.

 

I think that gives a misleading impression of the geography. So does Wikipedia's piece about the town, making it sound like a fishing village clustered around the port when the railway arrived.

The current port and railway were built as one project, and away from the village at the time. While there may have been a bit of mud to pull little boats onto, there was never a proper port before, and this was basically a farming community. By the time it expanded into a town, there was a barrier of railway and industry that stopped it getting close to the port until this was all closed down starting in the 1960s.

The railway served the port, its station was at the town end - hardly beyond the town, more off to one side. The pier station seems never to have had a regular service; I suspect it was to serve passenger ships which were never that regular (and packets if they ever used the port). And the new station was only built because the old one had to close to make way for the power station, in part using land vacated by the "other railway".

 
Portishead's original station was opened in 1867, half a mile beyond the town which, I note, was described as a "village" in those days.  The line was extended to a pier station in 1870, though that was shortlived as a passenger station.   On 4th January 1954, a new station was opened 400 yards short of the old station bringing it closer to the Town Centre, but that only lasted just over 10 years as a passenger station - to 7th September 1964.

https://www.portisheadrailwaygroup.org/history.html

https://en.wikipedia.org/wiki/Portishead_railway_station

As long ago as April 2007, we started discussing the re-opening of a station in Portishead - at http://www.passenger.chat/231 with a thread now up to 921 contributions.  The project feels (personal comment) to have taken an awfully long time even by rail standards, on what feels like one of the more obvious re-opening cases, with a complexity that I would have found depressing in 2007.

Picture - John Thorn, Creative Commons license - ((here))