More boats and barges should be seen on the River Lea in London after the opening today of Three Mills Lock.

This is the first new lock to be built in London for more than 20 years and  today being World Environment Day it was appropriate that Environment Secretary Hilary Benn should perform the opening ceremony. He is also staying in office as part of the reshuffled cabinet.

“We want the London 2012 Olympic and Paralympic Games to be the greenest games ever” he said. “Funding the Three Mills Lock will not only take many lorries off local roads, reducing thousands of tonnes of CO2 and local congestion, it will also provide a green freight route for the redevelopment of East London, and open up the waterways for boaters, walkers, and cyclists.”

The lock is just east of Three Mills and on the Prescott Channel which is part of the Bow Back Rivers network threading through the Olympic Park. It’s a spot which was well-known briefly as the site of the first Big Brother programme. It’s also where stones from the Euston Arch was dumped and thanks to this work they have been retrieved.

The footpath linking Three Mills to Three Mills Lock is currently closed.

Our ‘Walk London’ Lea Valley walk upstream from Limehouse took place in perfect weather: blue sky and sun but also a breeze.

Three Mills was empty but looked like a film set. Tesco saved the day with its toilets.

We followed two Bow Back rivers to reach the stretch of Greenway open. But this week security fencing has been put up at the Olympic viewpoint which is a pity.

Good to see old and new faces on the walk.

There will be another one on the last Saturday in September. Details will be posted here in late August.

Walk London organisers are suggesting we wear suncream, take a hat and and carry plenty of water on the walk tomorrow.

Sounds good!

See you tomorrow at Limehouse Station, 2pm.

I have checked our route for the Walk London event on Saturday and yes we can go up on to the Olympic viewpoint.

We shall take an unusual route between Three Mills and the Olympic Park as so many paths are closed but this is an unusual time. We can use a quiet canal-side path on the Bow Back Rivers to get there.

This week I thought that the Olympic Stadium really did seem huge for the first time. It is a big change from February and it is a landmark which will be with us for the rest of our lives. Walkers will be surprised.

Much of the blue perimiter fence has come down so now when on the towpath north of Old Ford Lock you can see into the Olympic Park.

We meet on Saturday 30 May at 2pm outside Limehouse Station.

The end is at Hackney Wick Station.

It’s free. All welcome.

And the weather forecast for Saturday is “sunny”

The latest information on the towpath closure between Ponders End and the Lea Valley Viaduct to the south is that it will remain closed between 7.30am and 6pm daily until Friday 10 July.

Diversions remain in place via Lee Park Way and Meridian Way.

The Electricity Alliance, a partnership between National Grid and Balfour Beatty, is currently refurbishing the overhead electricity transmission line between substations at Waltham Cross, Brimsdown and Tottenham. Work involves replacing the overhead line fittings, painting and work on the steel structures.

National Grid Project Manager Simon Chandler says: “These closures are needed to ensure that we can carry out the work safely. We apologise for any inconvenience this may cause and we will make every effort to ensure we complete the project as quickly and considerately as possible.”

We shall be going up to the Olympic viewpoint on the Lower Lea Valley walk on Saturday 30 May.

This event is part of Walk London’s ‘Spring Into Summer’ weekend and our walk also coincides with the Ramblers’ Get Walking Day.

We meet at Limehouse DLR Station at 2pm to walk north up Limehouse Basin, through Three Mills to Hackney Wick Station.

All Walk London walks are free.

www.walklondon.org.uk

The towpath between Ponders End and the Lea Valley Viaduct to the south is remaining closed this weekend 16 and 17 May.

The continued closure is due to essential work on overhead electricity cables.

But if work ceases early in the afternoon the path will be opened.

Those tempted to climb the barriers ought to remember that they will only come up against four further fences.

Although this work is due to continue until 10 July it it is hoped that continuous work now will result in an earlier completion date.

Pages 99 to 101.

Bottom of page 29 to middle of page 31:

Follow Parkway Road from the station forecourt (or right from the Luton path) to a roundabout. Turn left into Lower Harpenden Road. Continue ahead to go under the flyover and follow the path which rises to leave the roadside.

Only go left up the steps to visit Someries Castle (see page below).

Stay on the main path running parallel to the road below (right). Soon the way is fenced and high above the road. At a junction the path runs up a steep slope to run alongside the main railway line. From the high ground there are occasional glimpses of Luton Hoo mansion (right).

Top of page 32:

The “missing bridge” has been replaced.

Page 36: Diversion to Someries Castle

Go up the steps and left on to a path leading up to Airport Way. Turn right to cross high over the railway. Keep forward where the pavement ends and after a short distance turn sharp right to climb the steps up to the top of the bank. Here there is a view across Luton by the fence of Luton Airport.

Go ahead from the top of the bank and turn left with the airport fence to follow the path along high ground and then down into the valley.

At the bottom of the hill turn left to stay with the airport fence. On meeting a gate keep to its right to continue uphill. Stay with the fence as it bears round to the right, passing a clump of trees and a hedge. Go through a kissing gate on the left and bear half right to pass between brick Someries Castle (right) and the farmhouse. Go through another kissing gate by the track gate and turn immediately right to find the gate leading to the castle.

Return by the same route but when near the bottom of the hill do not go right up hill but continue ahead following the bottom of the valley to go under the railway by two cottages (right).

Turn left along the road for a few yards to find on the left a kissing gate. Once in the field keep parallel to the road. After a short distance bear left up a wide gap and before a tunnel turn right up a slope.

I have been looking at the path south of Luton Airport Parkway where there have been big road changes. The work has taken longer than expected and in addition Sustrans has begun work on a cycleway.

I was fortunate to meet Sustrans’ area manager Andy Knight on site. I shall shortly be posting a new text for the opening of section 3.

In future there will be no need to cross a dangerous road and walk under the end of the airport runway. Some will regret this maybe!

Thanks to Sustrans one can walk directly south on a safe path. Some of it is already newly surfaced.

Here the path is following an old railway line. Yesterday the ground was being landscaped around a new footbridge which spans the main road as the path moves to the west side.

At East Hyde, just inside Hertfordshire, work has started on the path running into Harpenden. There is is a gentle slope up to the old railway embankment from the road at East Hyde. A new hedge is in place to enclose the path.

I shall update on this area from time to time as there will be occasional diversions as work continues and other changes.

Some may regret the stretches of hard surface but overall this is a great improvement.

There is little signage at present. The old has gone, the temporary has blown down and the new has yet to come.

Pages 29 to 37.

The Highbridge Street car park on Cheshunt Marsh near Waltham Abbey is now closed for work to begin on the London 2012 White Water Canoe Centre.

Walkers passing Waltham Lock will see the gradual change and flooding of the flat area.

Page 89.