Sunday, 22 July 2018

How to check a bridge clearance before getting there

We did lots of exciting new stuff today, including Stanground Lock, an unusual windlass, a little-used waterway and a low bridge. I have included rather a lot of photos, but bear with me.

Opposite our mooring on Peterborough Embankment was this splendid old warehouse, complete with integral loading bay.

We were booked into Stanground Lock at 0900, so at 0840 we set off down our last bit of the Nene and looked for the right turn leading to the lock.

This must be it … but why the no entry sign?

As we got nearer it became clear that the no entry sign merely warned off using the wrong arch, and there was a sign - quite small - indicating Stanground Lock.

After passing some waterside houses and a boatyard we soon came to Stanground Lock and were checked in by Ashley.

The bottom gates are hydraulically operated and we stayed on board while Ashley worked us through.

Now we were on Well Creek … and into fenland.

The tight bend at Whittlesey wasn't a problem, and we came to the visitor mooring just before Ashline Lock.

We tied up and walked across the recreation ground to St. Mary's Church for the 1100 service. We were only a few minutes late. Afterwards we looked round the small market town and had a roast lunch at the Sunshine Café. We probably won't eat there again.

There are some interesting buildings in Whittlesey, including the Butter Cross and this former town hall and fire station.

Back on the boat we waited while a boat on the lock landing entered the lock, then we went to the lock landing. After days of seeing few boats at the locks on the Nene this lock, Ashline, was busy. We witnessed two boats come up and three go down, including us.

This was where I could try out the special Middle Levels windlass which I had acquired from somewhere.

The paddles - here called penstocks - take a lot of winding. I counted at least 60 turns. And the lock is very slow to fill - no danger of buffeting a boat coming up.

Having talked to various boaters I decided we would try the Twenty Foot River route, but we needed to see if we could get under a low bridge. Tying up at the lock landing below Ashline Lock I used a long batten and a tape measure to calculate that our air draft was 1.86m. Oh dear. According to the Middle Level Navigation Notes which the Stanground lockie had given us (and which our friend Tony had printed off for us in Northampton) the maximum air draft at Infield's Bridge was 1.60m.

Then I had a brainwave. The air draft at Angle Corner Bridge is supposed to be 1.95m, so Infield's must be 35cm lower. All I had to do was measure how much headroom we had at Angle Corner. If it was at least 35cm then we would fit under Infield's. We had 42cm to spare under Angle Corner Bridge ...

so we continued along the wide, deep Twenty Foot.

Eventually the low bridge got close enough to photograph. Would my calculations be right?

Yes! I reckon we had a good 10cm in hand.

So why were both bridges higher than advertised? It must be because the 'book' measurements were taken at a much higher water level than we are experiencing. According to the Navigation Notes there are only two bridges lower then Infield's: Bradford Bridge on Yaxley Lode (1.56m) and Exhibition (Stokes) Bridge on the Old River Nene (1.53m). If the water levels stay as they are we should be able to pass under both of them.

We weren't going to make it to March before the F1 Grand Prix highlights so we tied up to the reedy bank in the middle of nowhere.

Tomorrow we intend to turn right onto the Old River Nene to go through March and on towards Ramsey.

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