Of the 3 main rivers that run from Hampstead down to the Thames, all have a storm relief drain, to take away the excess water and prevent nasty fluids flooding the streets and people’s homes. The KSP doesn't have one that follows its length, instead it has a branch that leads to join the Ranelagh CSO. The Ranelagh storm relief starts north of Hyde Park not far from Speakers Corner. It then goes south to the Thames, gradually getting closer and closer to the Ranelagh CSO, until they join at the Thames.

The huge junction of the Ranelagh CSO and Ranelagh Storm relief, as well as the branch from the KSP CSO coming down from Piccadilly. The Ranelagh Storm Relief joins the Ranelagh CSO about 30m before this junction. In the picture below, the Ranelagh CSO runs in a channel beside the top of the dark wall and continues going down to the Thames. For a view looking down, see this photo from the GES032 Ranelagh CSO write up.

A wide shot of the massive junction chamber. Being here when in full flood must be amazing, although obviously one would be a bit drowned. The two slots are where the Ranelagh CSO flows by over my head in the picture. The smaller tunnel behind me is the KSP CSO branch. This huge chamber sits in front of the French Embassy in Knightsbridge. The term Knightsbridge, comes from a bridge that Knights used to cross the old river that the Ranelagh CSO replaced, roughly where the Ranelagh CSO is joined by the Ranelagh Storm Relief. Pic here for clarity.

For this trip, Kev, Gringz and I, decided to go up the KSP branch of the storm relief. You can see here where drainers (name given to those of us that explore drains) got the name for this drain, The Egg. While walking along I picked up a number of credit cards and an Italian Identity card. Obviously, thieves in the area use a drain lid near here to dispose of what they don't need.

Detritus caught on a rope at a manhole access to the drain. As manhole's usually sit in the middle of the road, they are only ever used in the case of extreme emergencies by drainers.

Looking up from the shot below to the platform where a long ladder goes up to the surface and a manhole.

Limescale deposits on the walls and ghostly imagery, with bits of toilet paper and baby wipes hanging from the ceiling.

Eventually half a mile later, we came to another large open chamber. The KSP CSO runs on the top of it. Kev sits on a pipe that brings in the Regent St CSO. The camera is looking down stream towards the Thames.

Closer shot of the southern end of the chamber looking South. The arch and chamber one can see on the lower right of the picture, is the start of the KSP branch of the Ranelagh storm relief we'd just emerged from. You can see a silver ladder that goes up to the surface on the bottom right of the chamber. Facing it on the bottom left is a more civilised set of stairs that lead to the surface. Mostly occupied by rats.

Stairs down to the KSP CSO and storm relief chamber. The lid to the surface a few more steps up behind the camera.

TRIP 2

Gringz and Kev made this trip. We walked from the giant chamber under Knightsbridge down to a steel flap   that impeded our progress. It was pretty uneventful and lacked any interesting features. At the steel flap, we had to walk all the way back due to the lack of side exits. That's the nature of exploring, the unknown.

TRIP 3

Sadly for the third trip, Gringz wasn't able to join us, so it was Kev and I. We found a lid passed the steel flap, and dropped down to the drain. We then walked back to the flap. Kev had been really working on his drain photography, and had now acquired a number of light set ups and filters..  The flap sits behind Kev in this pic, and then has 2 large steps down to where Kev is stood. Lighting credit for this pic goes to Kev.

A closer shot of the steel flap, and the stairs down.

Because this is a storm relief, there is no real flow of water through it, It doesn't act as a sewer. This is the drain as it continues south from the flap above. Because the water doesn't come from a sewer source, it's usually clear. Although I wouldn't want to drink it.

Kev was lightpainting further down the pipe, so I used his lighting to get this shot. As it's a somewhat arty shot (a rarity from me) I've put it into black and white.

Detritus on the walls, as the drain enters a RCP (round concrete pipe) section. You can see the grey concrete where the bricks run out.

A cross through section. The wooden boards hold the R CSO back from entering the storm relief, unless it reaches the top of the boards in a flood scenario.

As the storm relief reaches the Thames, it turns into a RCP section.

The penultimate chamber of the storm relief, and identical chamber sits through the flaps on either side of the channel split. In a flood situation the water would force the flaps open.

This is the final end chamber of the Ranelagh storm relief. On the other side of the flaps is the Thames.

Kev and I do a shot in the penultimate chamber of the Storm Relief. I thought the wooden plank was part of the infrastructure, but apparently it was used by other explorers to hold the steel flap mentioned above open.

For various reasons, there's usually a likelihood of bumping into a police entity in this area. So we opted to return to where we started. A wander back up the storm relief chamber.

Exiting back into the cold night air, another drain had been completed. Another chapter closed in the draining adventures under London.