Sewers, streams and floods – in conversation with John Bownas

The recent Hastings floods have led to some deep questions about what exactly is going on under the streets of the town… and why storm water doesn’t seem to want to stay where it is put. Jude Montague wants to know more about what we can expect, and talked to John Bownas, manager of Love Hastings (the town’s Business Improvement District).

Many people are asking if the £50m storm tunnel intended to stop flooding of the town centre is ‘fit for purpose’, and many more are loudly saying, ‘Told you so’ because of the town’s flooding history. John has taken up the challenge of trying to unpick myth from reality and get a full understanding of the hydrology of the town’s sewers and streams.

I asked him the big question first – isn’t it inevitable that Hastings will keep flooding?

“The short answer to that is an emphatic NO,” John told us. “Nothing is inevitable, and we already have a lot of the solutions either already in place or within our reach.

“The floods the town has seen over the years have come from a variety of sources. A long time ago we had the sea breach the road and leave roads underwater, we’ve had sewers full to bursting point and beyond, and of course more recently we’ve had stream water turn into full-blown rivers that have swamped the area.

“But despite alarms about rising sea levels it’s been a long time since the sea caught us out, and from the point of view of the town centre it’s actually been a long time since we saw significant flooding prior to 2023.

“More to the point, since Priory Meadow and the storm tunnel were built in the late 1990s, there have only been a few other flooding incidents – two of which were attributed to human error, and another to equipment failure. Broadly speaking, Hastings is getting to grips with flooding… I’m satisfied in saying that without the tunnel we’d have seen many more floods over the past 20 years.”

Why then, did Hastings get hit so hard by two floods in the space of 10 months this year?

Warning signs

“Well,” said John, “the warning signs about this went back a few years to 2017 when the beach outflow from the culverted stream outflow pipe leading from Alexandra Park broke and got buried under shingle.

“After this happened, during a few fairly heavy downpours, we saw localised flooding in South Terrace with water coming up through cracks in the road surface – something that hadn’t been seen much in the past…although it wasn’t unheard of.

“This raised everyone’s attention levels, and I wasn’t alone in asking both Southern Water and ESCC what was happening and who was responsible.

“Unfortunately, the response to these incidents wasn’t a quick fix to the outflow pipe, but rather the installation of a new manhole near M&S to allow for inspection and cleaning of that section of the culvert – which, by the way, was built for HBC by Sidney Little in 1937.”

Why do you say unfortunately?

“As I say, we were witnessing warning signs, and looking back it’s a bit like one of those old disaster movies where everyone ignores the earth tremors that turn into a full-blown earthquake. What we saw on at least one occasion was the M&S manhole cover pushed up by the water below – but back then the problem was contained in South Terrace itself, and nobody foresaw what might happen if the rain levels really increased.

“So what happened in January was a massive escalation of this problem, because the huge rainfall intensity we experienced back then saw so much water come through from the culvert manhole that it rapidly flooded the service yard of Priory Meadow and flowed right through into the town.

“Obviously, whenever it could, this floodwater tried to go down a drain, but that just meant it overwhelmed the sewers, and the whole system simply backed up because it couldn’t get the water out as fast as it was coming in.”

Solution(s)

So is there a solution to stop it happening again?

“Again, there is a short answer, and it is YES…

“But it’s not a single answer – we need to look at all of the different parts of the jigsaw.

“The first part is technically called ‘attenuation’ – broadly speaking that means holding back the water.

“Until he died aged 91 (still working for the council), in 1901 we had ‘Tom’ working at Buckshole Reservoir. He used to drain it down in advance of heavy rain so that it could hold back water and then later on release it gradually… I think we need another Tom.

“The town also installed ‘penstock’ gates at the bottom of Alexandra Park, and these were also once used to hold back water in the lower end of the park to protect the town. I think a conversation is needed about whether they should be reinstated.

“Looking at the bottom of the culvert, I think there is another simple issue to address… and that is the fact that the main 2-metre diameter pipe narrows to 1.2 metres for the last stretch across the beach. My vote is to add a second pipe out of the valve chamber so that hopefully the culvert doesn’t back up anymore.

“Then we have to look at the businesses around the centre of town that have flooded from their cellars or because of water pouring through their doors.

“It’s not perfect, but all of these need to be given individual solutions such as non-return valves on their sewer lines or locked-down manhole covers. And for those flooded from above they need simple flood barriers fitted to their doorways.

“Of course, after all of this, there may still be times when things get out of control.

“So we need level alarms in the critical pipes, and these need to give us time to make the really difficult decision about whether we open up the system to the sea and allow sewer water to flow straight out onto the beach rather than piling up in the basements of local businesses or the town’s streets.”

Who pays?

Who is going to pay for all this?

“The costs are actually not that great if these solutions are shown to be enough. So I would hope that Southern Water would pick up the bill.

“But more relevant is the question of whether anyone will compensate businesses and homeowners for the huge losses they incurred in January and October – and that’s what we are focusing on right now.”

Okay, it sounds like you have things in hand – but you mentioned a German U-boat?

“Oh yes, looking into the history of our sewers definitely pulled up some interesting facts… and my favourite is that when the council found itself with a derelict German U-boat washed up on the beach in 1919, the first thing it did was pinch the engine to provide the town’s first sewage pump! What a great story…”

 

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