Tunnels, churches and water around Pulborough

Sunday 28th September

Window at Greatham church

This was a trip run by the London branch of Open University Geological Society (OUGS), primarily looking at building stones used in some of the churches along the outcrop of Lower Greensand near Pulborough. The leader was West Sussex Geologist David Bone. The good thing about these trips is, as well as learning something geological, is getting to visit places I either hadn't known about, or I wouldn’t have got round to going to otherwise. A new, different perspective on familiar places, too.

I travelled by train along the south coast and up the Arun valley to Pulborough, the group meeting in the station car park at 10.30am. A very mild, dry and bright day, bright from the start along the coast, though the fog took longer to clear along Arun valley / north side of the Downs. The sun came through at Pulborough just as we were getting started. During the middle of the day, it was very warm (still too warm for me at times) in the sunshine.

Geology overview

The Lower Greensand (LGS) ridge here was the one on the southern side of the Weald Anticline, running from Midhurst and Petworth. It’s called Lower Greensand as there’s a lot of sandstone in it, only it doesn’t look very green. Any green comes from the marine mineral glauconite. Most of looks gold, rusty red, or dark brown from iron oxidation, or darker brown / grey where there are harder bands of ironstone.

It is subdivided into the Atherfield Clay, Hythe, Sandgate and Folkestone Formations named after the areas of the south Kent coast where they are exposed in the cliffs. These are in turn subdivided. The harder sandstones, ironstones and cherts were the main source of building stones before the about the Victorian era, in an area otherwise short of sufficiently tough, strong building stone material. We also saw a more gritty ironstone from the Gault Clay (GC) above the LGS, Ironstone Grit, along with Horsham Stone (mainly church roof tiles)  Sussex Marble (mainly church interiors) from the Weald Clay Group (WC).

To fit in with Sunday services at the churches, our first port of call was a sand mine.

Marehill sand mine 

Marehill sand mine

This was on the east side of Pulborough, the only mine in West Sussex. Work stopped just after the last war. Now it is a nature reserve managed by Sussex Wildlife Trust. During the autumn and winter, bats hibernate in the tunnels, meaning no access from October - March. David is the Geological warden here. It was as well David brought spare torches – it was dark inside.  We a good look round the network of tunnels dug out of the sandstone manually with picks during the C19th. The tunnels sloped southward following the dip of the beds. Shining the torch on the less weathered bedding inside, I could see the laminated cross-bedding, iron oxide staining: in painterly terms raw sienna, burnt sienna, Indian red. This was the Pulborough Sand Rock (PSR) in the Sandgate Formation - too easily confused to the similarly named Pulborough Stone (PS). The latter is part of the Hythe Formation which lies below the Sandgate. The PSR is self-supporting, therefore great for tunnelling into. Above it was the Marehill Clay (also Sandgate). This was where much of the ironstone we saw in the churches came from. David took sample pebbles to compare with some of the ironstone in the churches later. It weathers dark brown to burnt sienna. It is more clayey / less sandy / finer grained than the carstone from the Folkestone Beds.

The Churches

We looked round inside and outside, though mostly outside where the various building stones were more visible: The Pulborough Stone (PS) was widely used, mainly as dressed (squarely carved) blocks in the walls, along with window frames. churches we saw later. The ironstones were common too, We also saw some Malmstone, quarried flints from the Chalk of the Downs (black core), more weathered white and brown flints (exposed to air near the surface of the Downs) and Sussex Marble.

The interiors tended to be plain, with white plastered walls. An attractive mix of  stained glass and clear panes in the windows. The smaller churches had no electricity and were lit by gas lamps and candles.

Wiggonholt Church

We started with Wiggonholt Church on the ridge to the east of the Arun, near the RSPB reserve. The was of the smaller churches. Before we got eyes in on the walls, we admired the view from car park of the South Downs escarpment towards the Arun gap. The Wildbrooks are in the broader, very low lying floodplain between the LGS and South Downs ridges. To the west, the Rother joins the Arun at Hardham, to the east, smaller streams. In winter, the area is frequently underwater – see my watery notes later.

It felt very warm in the sun in the churchyard, enough to send me scurrying into the shade. This was one of the smaller, single room Wildbrooks churches, roofed with tiles cut from Horsham Stone.  Inside were, gas lamps, no electrics.

Our lunch stop was at the café  / visitor centre at Pulborough RSPB Reserve. Here, there was a view from tea terrace overlooking the eastern Wildbrooks, though unfortunately we arrived at peak time, when all the tables were taken. A big queue inside for food and drink. Not surprising it was packed out, being a Sunday, fine weather David wondered if flat topped hill where the car park was one of the Arun river terraces, i.e. the past level of floodplain, the river subsequently cutting downwards. There were flints amongst the sand, which would have gotten there somehow or other from the Chalk – assuming, of course they hadn’t been put there by a big truck to lay out the car park, no paved / madeover tracks, though.

Parham House

Parham ("Parram") Church – A church with a bell tower on the west side, and annex behind it on the south side, situated on the Parham estate, near Parham House. That’s the stately home we’ve seen from Rackham Hill, being built beneath the Downs escarpment, separated from it by a small valley. Much of the greenery around the house given over to parking, there being an event on. The church and house lie on the  Folkestone Beds (FB). Near the north wall, a line of oak trees and an unusual looking clump of fungi which appeared to be growing straight out of the grass, though more likely from a buried branch or trunk. Much of the building stone comprise Pulborough Stone. The dressed blocks were rich in pale lichens and weathered to a fairly rough, laminated surface. Some of the newer, less weathered stones around the window frame near the annex had grey streaks. The annex looked obviously different: smaller pale grey and pale brown blocks. This was Malmstone, from the Upper Greensand, a thin outcrop between the Chalk and the Gault. Inside, a font carved of Sussex Marble. This grey and very shelly, containing fossilised snail (gastropod) shells which were most obvious in the polished stone . Strictly, it is not a marble (metamorphosed limestone subject to intense heat / pressure), but a sedimentary limestone. A slab of this at the entrance, too, rough and not polished.

St. Peter's Church, Parham

The South Downs from Parham church

Fungi at Parham

Greatham church

Greatham ("Gretham" ) Church. As at Wiggonholt, a small, single room unassuming building. A small spire on the west side. It was situated lower down nearer the floodplain on the east of the Arun, along the lane from Greatham Bridge. The churchyard was now a metre or so above the surrounding ground, dipping down again to the entrance on the south side. Over the centuries, burials had raised the ground level. Though, C12th we noticed a filled in middle window between the glazed windows on the east wall. As this was common in Saxon times, this suggested there had been an pre-existing building here. An abundance of, for want of a name as there isn’t one, Marehill Ironstone. More Pulborough Stone with grey streaks, too. Inside, simply decorated with plain plastered walls. Again no electricity, hence the gas lampas hanging from the ceiling and the candles at the altar. The sun shone through window at the west end, projecting the colour on the stained glass onto the recess of the arch. As at Parham, some Sussex Marble.

Greatham church interior

Leaving the church to head to Stopham, crossed Greatham Bridge and turned right onto the A29.

David pointed out two more churches near the main road: Coldwaltham (L), Hardham (R). Crossed the Arun again at the A29 London Road bridge and the A283 via Lord Young of Graffham's bridge alongside the old Stopham Bridge.

St. Mary's Church, Stopham

Stopham Church - our last church of the day, some way up the hill from the river, off the lane north towards Pallingham. This was built on the Pulborough Stone outcrop and made wide use of it. The stones  here were particularly varied, with some larger blocks, PS and chert. Ironstones were  very common, too: the “Marehill” and Carstone from the Folkestone Formation.

Stopham Bridge, the quarry, River Arun

Quarry in the Folkestone Beds, Stopham

Leaving the churchyard, we turned left and walked a little way along the lane to look at the wall of a farm building on out left. Blocks here a uniform size – local Pulborough Stone. Here, we thanked David formally for leading our tour of churches. There was time, though to visit the quarry in Folkestone beds just upstream of Stopham Bridge. For this we parked near the White Hart. A view of the old Stopham Bridge from the riverside garden. The quarry was just upstream of the road bridge. I’ve passed this quarry when walking to Stopham Bridge along the footpath off Coombelands Lane on the north side of Pulborough. This was the Folkestone Beds. Though the bedding planes were linear, it all looked contorted, riddled with layers and veins of carstone, curving pipe formations. As an artist I liked the mix of earthy golds and reds, with darker greys.

Stopham Bridge

The White Hart pub was hit badly by last winter’s flooding, particularly over Christmas. It’s been closed ever since. Badly hit by flooding in the January 2003, too. A quick look at the pub’s Facebook page indicates that they plan to reopen at the end of October under new ownership. I wish them all the best,  nonetheless, particularly susceptible location. Riverside pubs may be pretty in the summer, but…

Sensibly, all the churches were visited, likewise most of Pulborough have been built comfortably above the floodplain.

When David talked this morning at Wiggonholt about the Wildbrooks and flooding in the floodplain, he mentioned the particularly bad flooding last winter. I remember the view of the big lake we saw from Bignor Hill late last December well. David said that it’s not just a case of floodwater spilling down the Arun from the Weald round Horsham way; the Rother from Selborne way; and the tidal effect. Because the Downs gap is relatively narrow, drainage of floodwater away to the sea is impeded and backs up round the Pulborough area.

Today, the river was gentle and languid looking here, though I wasn't the only who noticed it was  flowing the wrong way.

All headed back to the station about 4.45pm, from where we all headed off. As I had at least half an hour to wait before my train, I walked down the bridges at the A29-A283 junction. Crossed the A29 at the road island opposite the antiques place. The old London Road bridge was off to the left of the newer one. Between the bridges a pump. Stood on the old bridge, now a foot-cycle bridge and viewed the Downs escarpment. Again here, the river ran gently, though with a definite tidal current, flowing upriver towards Stopham. I had my ginger muffin, debating which of the building stones of the LGS it most closely resembled in colour and texture – the ironstone from Marehill, the Folkestone Formation?

Pulborough - A29 (London Road) bridges old and new

Note on water levels

The Met. Office say that this September has been in the driest in the UK since their records began in 1910, with only a fifth of the average rainfall. It’s also been one of the warmest. They say October will be more unsettled, though as it’s started off warm, pressure still high, I’ll believe that when I see it. 

Further to what I said a fortnight ago (Notes along the Mole, Wey and Thames), there isn’t a drought yet and overall I don’t think anything, anyway is any lower than it was at this time last year which had a drier summer. The Met Office press release (29^th September says that this year overall has been wet, though that’s largely down to the record soggy winter. The Environment Agency said in their latest Weekly water resources report for England & Wales (17-23 Sept) that many rivers in impervious catchments have been running below normal, reflecting the very dry weather this month. The Swale in North Yorkshire and the Tone in Somerset (drains Somerset Levels another area badly hit by flooding last winter) exceptionally so. Among the others were the Derwents of Cumbria and North Yorkshire, the Severn and Wye, the Eastern Rother in East Sussex. Most other river and groundwater levels have been in the normal range, it’s the normal range for September, when they tend to be at a minimum. After the highs of last winter, groundwater levels at Chilgrove near Chichester fell sharply (EA Weekly water levels: Hampshire, West Sussex, IOW, 25/09/14) It’s now down to the level it usually is at this time of year, when groundwater levels tend to be at their minimum after the summer. Likewise river flows on the Itchen and Test. It seems, then that the record wet winter of 2013/14 saw us more than comfortably through the summer, everything still needs topping up now. In monetarist terms, last winter’s rain topped up the savings account, but it’s all / nearly all gone now following a spendthrift a combination of an early mild spring and warm, extended summer. Not that this is the first year that September /the early has been dry and more like summer. September 2003 was warm and very dry. The ground looked much more parched than it does now. In 2011, there was a heatwave at the beginning of October after a relatively cool summer. 1997 was similar to both: still shirt sleeves along the Arun as today.