In the 1860s Joseph Bazalgette built a huge tunnel within the Victoria Embankment to help solve London’s sewage crisis. 150 years later engineers decided it needed urgent backup and set about building the Tideway Tunnel. One of the key sites was at Blackfriars Bridge where the Fleet sewer overspilled into the Thames at times of heavy flow, repeatedly damaging London’s eco-credentials. A huge worksite thus had to be built in the heart of the City, the proposed solution an offshore wedge which could later be transformed into a new public space. When I wrote about the plans in 2016 the intention was for the extra three acres to open in 2022 with the 14 mile tunnel fully flushed by 2023. In fact the Tideway Tunnel first flowed last February and the additional public realm at Blackfriars only opened earlier this week. It’s called the Bazalgette Embankment, and I have taken far too many photos of it. [25 photos]

It’s enormous, indeed the largest single structure built into the River Thames since Bazalgette’s initial work, and if you stand on Waterloo Bridge you can easily see how much it sticks out. Better to approach from Blackfriars Bridge however, partly because you get a much closer top-down view but also because a new staircase finally reconnects the pavement to the embankment below. They really want you to come down here and enjoy the new public realm, which makes a nice change after almost a decade of not being able to walk along this side of the riverbank at all. On the descent you can get up close to the floral ironwork beneath the main span and then, before you enter the Embankment proper, go peek at the massive bobbly intervention underneath the bridge. The Fleet used to emerge here from a piddly sluice but the entire riverbed’s now been capped to ensure no brown sludge ever escapes again.

This is the thin end of the wedge so also the least decorous, but there are still several odd-shaped benches where you can rest and take in the riverside ambience. Part of the space is being taken up by a long pedestrian ramp descending from above and this has created an extensive undercroft sealed off by unpolished metal panels. A set of public toilets has been tucked away in the centre - yet to open - but the remainder is a mysterious secret lair from which workmen pushing barrows occasionally emerge. The ramp up top is a more tempting entrance for most visitors, passing a totem with all the project’s background info before stepping down directly onto a long planted terrace. This maze of beds includes 71 young trees and its design is supposed to ‘reference the path of the lost River Fleet’ from woodland to meadow to marsh, although I confess I couldn’t see it myself.

Scattered around the Embankment are five large black sculpted forms called The Stages, created by Nathan Coley. They’re varied, dark and slabby, in some cases sheer surfaces and elsewhere something you can actually walk on. They also have names, so the thin pillar near the bridge is Kicker, the pair beside the river wall are Twins and the longest wiggle is Zigzag. The tallest sits in a stepped pool and is called Waterwall, so I assume it’s meant to double up as a dribbly cascade for children’s summer frolics. Best not imagine the actual liquid barrelling underneath on its way to Beckton Sewage Works. I liked the basalt quintet more before I read the associated artbolx (including claims that the ‘playful and interactive assembly’ creates a ‘lyrical happenstance’), but they integrate well and I concur that the larger platforms could indeed double-up as a venue for cultural programming.

Along the former Embankment wall are several bronze lions with large mooring rings in their teeth. They’re 1868 originals by Timothy Butler and line a mile of river, encouraging the urban legend that if the water level ever reaches the lions’ mouths then London will flood. It won’t happen here because they’ve been relocated from Bazalgette’s original walls, but this has provided a rare opportunity to get up close to a leonine London icon rather than simply staring down from above. The uppermost lion has been nicknamed ‘Roary’ whereas the others await comical christening. Check the side of the westernmost lion for the plaque unveiled by King Charles when he visited in May to mark the tunnel’s completion. The row of electronic bollards alongside has not yet had to be raised because the pavement connection remains a fenced-off worksite while final snagging works continue.

At the broad swooshy end of the Embankment the scale of the engineering becomes clearer. There’s easily enough space here for an audience to watch a small performance or for stalls to be set-up for some organised event, even to play five-a-side kickabout. Look down and the reason for the lack of intermediate infrastructure should become clearer, it’s because the paving is liberally scattered with rectangular access covers. They’re needed because this public realm is really justuseful camouflage for an awful lot of critical pipework above the main shaft, hence the phenomenal number of recessed slabs - I lost count around 70. The ribbed rotunda on the nearside has too small a diameter to cover the invisible drop shaft and according to original plans was intended to house a control cabin, but will perhaps end up as the inevitable cafe.

The western tip is where you’ll find three twisty columns, more grey than black, a signature artwork also found at other Tideway sites along the Thames. They’re actually ventilation shafts - best not think for exactly what - and their edges are inscribed with hard-to-read lines from commissioned verse by Dorothea Smartt. Ridiculously the poems are only available as graphics on the Tideway’s website ‘due to artistic restriction and copyright’, whereas anyone can stand beside the sculpt-trumpets and read "The Furious Fleet flows red with Roman blood, Boudica battles bravely." Meanwhile alongside this poetic trio is a small raised terrace, large enough only for a few tables, and also a dead end so its purpose appears to be as a viewing platform. Maybe it’ll be cappuccinos only later.

The Bazalgette Embankment is a welcome addition to the City of London’s longstanding lack of public open space and a cunning solution to the problem of how to hide a former construction site in plain sight. It’s also a veritable trip hazard throughout with so many steps, seated areas and changes of level around the central flat piazza that I anticipate a regular slew of accidents. I suspect the Embankment will look at its finest on a sunny day but I loved the glistening sheen created during yesterday’s horrendous rain, weather which fortuitously discouraged other visitors and permitted me to create an album of essentially vacant photographs. Also I understand there’s only one more of these riverside protrusions yet to open to the public, so when King Edward Memorial Park in Stepney joins the throng I should probably go out and catalogue all seven.

» 25 photos of the Bazalgette Embankment