Yesterday, as well as the main canopy support spar going up by leaps and bounds (IYSWIM), there was also a guy up a ladder examining the end of the Brunel Plaza structure. I imagine the P7 canopy has to interface here in a similar way to what happens along the G3 frontage (backage?).

Looking at the size of the vertical members up against the 3 Guineas (which has been cut away slightly in some places), they must be there to provide rigidity not to bear any significant weight. Obviously any watertight seal can only cope with a very small amount of vertical movement, and these broad canopies balanced on a relatively narrow beam will be really quite floppy in high winds. The reinforced concrete frame of the Brunel Plaza, unlike Victorian masonry, may be able to withstand the forces involved and so perhaps take a direct attachment.

Also last night, P3 was mostly ready, and workers were clearing debris off the rest of the station end. There's still a bit at the far end of both P3 and P7 that looks to need a bit more building work. All in all, a lot of night-shift work underway even before midnight - a sign of deadlines looming?

The in-service date for these units has slipped several times since the original announcement (deliveries spread over May-December 2013 I think). SWT^▸ (South West Trains) have now updated their last news item (which just said "starting to introduce the fleet of new carriages into passenger service during the winter"). This now says (of the ex-460 458/5s):
... and:

Paul Clifton on BBC^» (British Broadcasting Corporation - home page) South news was adding a bit more context to that bit about "a lot of work", saying that SWT had found as many as 200 faults on the trains we have seen sneaking up and down the line on test. Alstom/Wabtec had, they said, underestimated the work involved, and Alstom's statement in reply did not really try to rebut that.

That's why I was surprised - I'd expected it would be (in some sense) tiled, and so would only need to be screeded level. But the way they were using their hands to shovel concrete from one step to another was really very quaint.

RBC^‡(resolve)'s contractors have been slowly pouring concrete to form the steps down into the pedestrian pit, and have now got to the top flight. I was wondering how they had formed the smooth top of the steps, and (while it's not in the photo) I now know it's just a lot of scooping up of the surplus by (gloved) hand and then using a plasterer's trowel.

And yesterday both P10 and P11 were out of use, as well as P9, and P8 except to or from the Westburys. So I was expecting something new in the trackwork from P10 and P11 Westwards - but I couldn't see anything.


Indeed - a canopy support kit has been delivered to P7, presumably not by big crane this time (nor for its erection). And some smaller supports have appeared along the back (or front) of the 3 Guineas.

Ah - the rebar mat was laid yesterday, over half the width of the concrete bed. I still can't see any sign of it poking out of the seaward face to tie in a new facing. There's a scaffolding parapet that appears to have been built on the old retaining wall, while the edge of the pour is defined by a row of beat-up old blocks you'd expect to as the base of a parapet or fence. Maybe that's been lined so the concrete isn't keyed to it and it can be taken down? Maybe - you do get the impression the method has been chosen for speed, or perhaps to avoid a design phase and any pre-manufactured parts.

Indeed - complaints staff complaining about being flooded with complaints due to flooding ...

Odd. During the week (Thursday?) BBC^» (British Broadcasting Corporation - home page) South were running a news item, which I never saw online, about a letter some of the SWT complaints staff had written to them, complaining about being overwhelmed with work and getting no support from management.

Yes, a huge amount of concrete has been poured, but not to make a new retaining wall (which I too had expected). The "embankment" (rubble fill) has been replaced by a mass of unreinforced concrete, including a wall of concrete blocks placed to act as "shuttering". Yesterday afternoon they were putting rebar mesh somewhere, though I couldn't see where.

While the weather has been a lot calmer, you can see that sand is still blowing over everything. You could see a thick layer of it on some layers of concrete as the next was poured on top. I would have though that would weaken the join, especially with no reinforcement running through.

Some of the old masonry wall is still just visible, and it may be that the plan is to rebuild that so it looks the same. That can be done later, is it is no longer structural. However, with a solid mass of concrete behind it, to which it may be tied by steel as well, it can still be stronger than before.

How the road is rebuilt may depend on how the houses are underpinned - if they are. Just backfilling the hole may be enough to hold up the road, once the houses are seen to.

I have a book called "The Berkshire Weather Book", put together mainly from newspapers. It includes Thames floods even if the rain in them fell upstream. I've gone through trying to pick out the years for which it records major floods, to give you an idea how many there have been (but I've probably missed some) . The book came out in 1994.

Of course the amount of rain that produces a major flood has gone up as work has been done on the river, but all these river floods would have flooded a similar number of houses to this year. Places like Old Windsor would of course get some flooding most years, and before 1900 only the bigger ones are in the book.

Major Thames floods:
Mar 1774*
Jan 1809* (snowmelt)
Nov 1852* ("Wellington's flood")
Nov 1875
Nov 1894*
Feb 1897
Feb 1900 (snowmelt)
Feb 1904
Apr 1908 (snowmelt)
Dec 1914/Jan 1915
Jul 1920
Jan 1925
Jan 1926
Jan 1928 (snowmelt)
Jan 1936 (snowmelt)
MAr 1937 (snowmelt)
Mar 1947* (snowmelt)
Jan 1949 (snowmelt)
Jan 1951
1974
Dec 1979 (Boulter's weir blocked by barge)/Jan 1980
Feb 1990

The asterisked ones were the biggest - from reports, much worse than this year (on the Thames).
Looking at the 1920s, even the last ten years isn't exactly "unprecedented".

Major flash floods (may also give some river flooding):
Feb 1883 / 1901 / Jun 1903 / Jun 1910 / Apr 1913 / May 1932 / 1943 / Sep 1968 / Jun 1971 / Mar 1979 / May 1993

Of course this is timetabling, so lots of different factors have to be juggled into place at once. Striking a balance between reliability (recovery time) and rolling stock usage is one, what paths are possible in the overall timetable is another. The other end may be more important, as at Waterloo where platform dwell and paths are highly constrained.

In this case the two journeys are very similar in length, but the Waterloo trains do a cycle in 3:30 while the FGW^▸ (First Great Western) ones take only 3:00. They alternate slower to Redhill with faster to Gatwick, which is an added constraint. The time at the other end is not actually any longer than at Reading, so it looks as if the crew break is not the most important factor, at least in this relatively short round trip.

If two trains per hour will have to go to Gatwick, to justify the cost of that shiny new platform 7, I wonder what they'll come up with as a pattern then. So far the effect of having P7, and putting Gatwick Express trains into P5-6, is that some FGW trains now dwell in P2 rather than using P3 and briefly lurking in a siding.

I've always assumed it's because the FGW^▸ (First Great Western) trains are "home", and change crews. If a train is very very late they can (sometimes) find a replacement in the depot for the new crew to take out. The SWT^▸ (South West Trains) trains are "away", and the crew takes a break before going back with the same train.

You left out "London Oxford Airport (OXF^» (Oxford - next trains)/EGTK - Kidlington)". Being the far side of Oxford, it's just about twice as far as Luton.

Most of us find it easier to make sense of rainfall in millimetres, since both large areas (in square metres or square anythings) and volumes of water are hard to visualise and their ratio ever more so. So why, you may wonder, do the French use litres per square metre instead? Of course it's exactly the same quantity. Another example of the way us and the French will find different ways of doing the same thing wherever we can?

The Airtrack TWA was really about extending the line from T5 to Staines - reinstating it, if you prefer - in the sense that that was the only unavoidable bit of major works. I was always baffled that it need to have all this detailed consideration of how many trains run over a level crossing miles away. TWAs don't usually say much if anything about services - look at the one for Reading, it has not a word.

So why not just do that bit, and have all the arguments about the value of protecting Staines Moor from having a railway squeezed in alongside the M25, and extend trains to Staines ASAP. In terms of journey opportunities or travel times to the Airport that give 80-90% of the benefits of the whole Airtrack scheme. Any ideas about direct trains further, and putting in (or, again, reinstating) the Chord, need to be justified against changing at Staines.

How many trains run through Wokingham is an entirely separate issue. No-one really expected Airtrack to be a stand-alone branded service anyway, and if it ran as part of an SWT^▸ (South West Trains) franchise that would set the service level. (Though I do wonder whether DfT^» (Department for Transport - about) could or would set a maximum number of trains to protect road users at the crossing.)

The other big issue that would need to be dealt with at this first stage is rail traffic (i.e. passengers) through Heathrow. The various parties have different interests in this, most obviously HAL who would like to prevent it altogether. Transport systems types would love an interchange at the airport, though I suspect the T5 "box" may not be big enough to hold all their aspirations at once.