Whitby Harbour : Maintenance Issues abound

The 2 Whitby pier extensions

I was delighted to read Alexandra Wood’s excellent article (Yorkshire Post, 17^th February), relating Mrs Sue Boyce’s heroic struggle to recover monies belonging to the Whitby harbour fund. This fund was set up under the Whitby Urban District Council Act of 1905, to ring-fence monies for the purpose of maintaining, repairing and developing the harbour. However, for many years the former Scarborough Borough Council (SBC) illegally diverted huge sums of these monies to projects not associated with the harbour.

However, the harbour has deteriorated not only due to SBC’s withholding of vital funding, but also due to their inadequate inspection regime, non-existant maintenance, a lack of professionalism and the absence of wholehearted commitment.

Whitby depends on its two main piers and the two extensions for a number of reasons. To protect the town from flooding and erosion; to safeguard lives, livelihoods and property; to shelter the harbour-based lifeboat and marina; to service the fishing industry; to provide safe passage in and out of the harbour; to provide a harbour of refuge for passing shipping; to help promote tourism and to prevent sand from Whitby beach migrating into the harbour.

The piers and their extensions were designed to act as a single unit. They are interdependent; if one of them was to fail, the remaining three could not function properly by themselves or even survive indefinitely. The effectiveness of the four structures working in unison is best demonstrated on a stormy day, with the sharp contrast between the calm waters in the harbours and the tempestuous seas outside.

Currently, the major problem for Whitby involves the two extensions. These structures erected between 1908 and 1914, were constructed with insitu-unreinforced concrete founded on a mudstone strata. Each extension was cast in separate sections adjacent to one another to form a single foundation. The major weakness in the original design centres on the interface between the foot of the concrete foundation and the mudstone. Without the introduction of some protective ancillary measure, there is nothing to prevent the sea scouring and carving out voids in the mudstone beneath the foundations. To overcome this problem Whitby Urban District Council in 1959/60, installed a line of scour protection around the entire 680m combined perimeter of the two extensions. This comprised of steel sheet piling with an insitu concrete backing.

Following a dive survey of the extensions in 2008 SBC’s consultant, Royal Haskoning, advised of the existence of a massive void at the landward end of the East extension measuring 8m long x 5m wide x 2m deep. They warned SBC that there was distinct danger of an immediate collapse of the extension in this location. Eventually, an emergency repair was carried out in 2010/2011 at a cost of £2.8m, wholly funded by DEFRA. This involved filling the void with concrete and installing 75m of new steel sheet piling.

In the report they published in 2009, Royal Haskoning provided details of the data produced by their 2008 dive survey. In summary, it revealed that approximately 36% of the steel sheet piling to the perimeters of the two extensions had either disintegrated, been holed or become excessively corroded. The worst affected areas were the east sides of both extensions and their seaward bullnoses. Furthermore, they also recorded the existence of ninety-five further voids, which had started to develop in the mudstone under the extension foundations. These penetrations varied from a mere 0.3m to a concerning 2.0m under the foundations.

Royal Haskoning gave the remedial work to the extensions’ defective steel sheet piling a ‘high priority’ rating, i.e. this work was to be completed within five years (2014). However, due to insufficient funding being available, SBC decided that the repairs to the East and West piers must be given priority over those to their two extensions. Consequently, Royal Haskoning condoned the deferral of the remedial works to the two pier extensions until 2032, subject to two strict conditions:

1. That a dive survey be carried out every five years to monitor the voiding under the foundations and the continuing deterioration of the scour protection works. This information would determine if there was a need to intervene and carry out further emergency repairs before 2032. Dive surveys should therefore have been undertaken in 2013, 2018, and 2023.
2. That horizontal core samples were to be taken at the base of the extensions’ concrete foundations, to enable the engineers to ‘better understand the erosion process’. There has always been a suspicion, that during construction some of the concrete might have been poured from too great a height onto the hard mudstone, causing it to sieve itself. If consequently, areas within the foundation are in fact made up of mortar rather than concrete, then such areas could be very vulnerable to scour.

In response to FOI requests, SBC were unable to confirm that either a dive survey or an underwater survey using hydrosonic techniques had been carried out on the total perimeter of the two extensions since 2008. They also had no record of horizontal core samples being taken.

By not conducting the dive surveys and taking the horizontal core samples, SBC deliberately chose to remain blind in respect of the present condition of the foundations to the two pier extensions and their scour protection.

1. SBC paid hundreds of thousands of pounds to a renowned consultant, Royal Haskoning, for their professional services. Then they decide, without explanation, to ignore the two strict conditions they imposed in order to enable them to postpone the remedial works to the two extensions until 2032. Why would anybody do that?
2. Since SBC were unaware of the present status of the extensions’ foundations, they had no way of knowing if they needed to intervene with an emergency repair. Nor even what form this intervention might take. They might justifiably anticipate that the steel sheet piles would have deteriorated further and the volume of the voiding increased, in the long sixteen years that have elapsed since the last dive survey in 2008. However, they have no idea of either the magnitude or the gravity.
3. The horizontal cores samples have not been taken. Therefore, it is not possible to establish if there is a problem with some of the concrete in the extensions’ foundations.
4. SBC’s conduct in respect of the monitoring of the foundations to the extensions is bewildering, negligent and reckless. In the event of a collapse, what possible excuse could they offer?
5. The irony is that on 1^st April 2023, SBC passed away and the poisoned chalice was passed to North Yorkshire Council (NYC).

So what should NYC do? They should immediately instigate an enquiry to determine who is responsible for creating the current unacceptable lack of knowledge in respect of the foundations to the two extensions. Then they should also commission a hydrosonic underwater survey of the two structures. Depending on the results, they may well need to instigate some emergency repair.

SBC’s record of accomplishment in respect of inspection, maintenance and some health and safety issues associated with the Whitby Piers is far from distinguished. The present situation is both embarrassing and unacceptable. Therefore, NYC needs to demonstrate strong management to the people of Whitby, and create clear blue water between themselves and SBC.

Vin McLaughlan

Egton Bridge