Planning Matters by Desmond Brennan - 09 June 2010

The Altmouth pumping station continues to occupy a significant place in the work of the Society’s Amenities and Planning Subgroup. We have now received a first response from the Environment Agency (EA) to our recent Freedom of Information Act (FOIA) enquiry. Not all the information we requested has been disclosed, but the EA have now promised to provide by 21 April all the missing information as further detailed by me. However, the information now available to us is extensive, including as it does the second Form G Report (the Project Team’s application to the EA’s National Review Group for additional funding for the refurbishment), and we have learned important new information.

The FOIA enquiry has provided us with data concerning the energy requirements of the four storm pumps, data which we tried repeatedly but unsuccessfully to obtain during our numerous engagements with EA representatives. Each storm pump under normal running conditions will consume 592 KW, viz. a total of 2368 KW for all four pumps. The four dry weather storm pumps, together with the ancillary equipment, require approximately 600 KW, making the total steady power necessary for the station to deliver the promised standard of flood protection to be close to 3.0 MW. This figure has to be considered in the context of both the power that will be available from the Scottish Power network and from the on-site backup diesel generator.

The maximum steady power available from the network is just 3.0 MW. Because of its importance, but not having information about the storm pumps, I had earlier estimated the power consumption of the station indirectly by applying basic physics to data available in the Halcrow modelling report and found it to be approximately 3 MW. Thus, even before becoming acquainted with this latest information, we recognized that the power requirement will be right on the limit of what will be available from the network supply. We repeatedly warned the EA that there was negligible reserve of network power and, eventually, they gave us an assurance that they would convey our concern to their engineering consultant. We remain critical that the power requirement of the station under storm conditions should be on the limit of what is available from the network supply, especially having in mind that the network is likely to be under pressure in such circumstances. However, we take comfort in the knowledge that any shortfall can be made good by the on-site diesel generator; we have been assured that each storm pump can be independently connected to either the network or the backup generator.

The on-site diesel generator is 2.5 MW which is just sufficient to supply under steady operating conditions the power requirements of three storm pumps, the four dry weather flow pumps and the ancillary equipment, although again there will be negligible reserve capacity. We had pressed repeatedly that the on-site generator should be capable of driving three storm pumps, but we could only obtain an assurance that it would be sufficient to operate just two storm pumps, so we are very pleased to have this latest information that the stand-by generator will have the capability of driving a third storm pump under steady operating conditions. In this account of power requirements, the reference to steady operating conditions has been deliberate, because there is a major issue arising from the very large spike in power demand when a storm pump is started.

The transitional starting power demand of a storm pump is approximately four times its steady state load, but fortunately this surge lasts for only a matter of seconds. Scottish Power has given an assurance to the EA that this potential source of instability will have minimal impact on their network. However, it is interesting to note that, as at 7 October 2009, the EA estimates that there is a 30% risk of constraint being imposed by Scottish Power on account of the pumps’ start transient loads causing network problems. Similarly, the supplier of the diesel generator has stated that their equipment will be able to withstand the transient surge at startup, even for the third storm pump. However, it is a little worrying that they found it necessary to add that in the unlikely event that the generator is overloaded, it will fail safe and will be operator resettable.

There is no reference in the second Form G Report to the possibility of there being a reserve canister storm pump stored on-site ready to be substituted within twelve hours for an out of service installed storm pump. We had earlier vigorously pressed the case for having the necessary pumping capacity delivered by three installed storm pumps, with a fourth installed storm pump as backup. Given that configuration is now a lost cause, we shall continue to press that there should be a canister storm pump in reserve to reduce the risk that the promised standard of flood protection cannot be delivered when it is needed.

After months of no communication from the EA, I was surprised and pleased to receive last month an invitation for a conducted tour of the pumping station and, in the event, Jack Gore and I had a very interesting and enjoyable visit. We were able to see and discuss the full range of the refurbishment work in progress. We came away with the impression that the process was being well managed and was being conducted with urgency. However, we were concerned to learn that there will be a period when our flood protection will be down to only one of the two remaining diesel pumps, so we must hope that, when that happens, we will be enjoying an extended period of dry weather.

Finally, on the topic of the pumping station, I received an invitation to attend the meeting of the Council’s Overview and Scrutiny (Regeneration and Environmental Services) Committee on 13 April to hear a presentation by a senior representative of the EA on land management and flood protection in the Alt Crossens catchment. This is involves many complex and difficult issues (the management plan runs to 498 pages!), but its specific relevance to the Altmouth pumping station was the reference to the Lunt Meadows flood storage scheme and the computer modelling study that is in progress for it and the wider area. I was able to make the point in this influential forum that, although the specification of the refurbished station had been arrived at as though the storage scheme existed, the scheme itself is still at the planning stage and as yet the Project Team for the refurbishment has no understanding how it would affect flows at the pumping station. Indeed, there is no certainty that the scheme will be approved any time soon, notwithstanding that the Project Team anticipated the scheme would be in existence at the same time as the pumping station refurbishment programme was completed. We shall continue to do our best to make sure there is a proper understanding of this point when further consideration is given to the measures necessary to secure an appropriate degree of resilience for the station.

Regular readers of these reports will recall that we have had an ongoing engagement with the EA concerning the condition of the Downholland Brook embankment, which is essential to the flood protection of Formby. As part of Atkins work for the Lunt Meadows flood storage area prior to 2006, physical tests were carried out on the Downholland Brook embankment as a result of which Atkins reported the embankment to be in poor condition. The strengthening of the embankment was a substantial component of the planning application for the Lunt Meadows scheme which was approved by the Council in August 2006. When that scheme failed to obtain EA approval, the strengthening was said to be scheduled, but later the EA claimed there was no need for any remedial work on the embankment; the latest FOIA enquiry has confirmed our suspicion that there is no documentary evidence to support that decision. We have continued to press the EA to take proper account of the Atkins investigation into the condition of the embankment and not to discount their concern for the embankment’s stability. We are pleased, therefore, that at last the EA have now commissioned a consultant to investigate the condition of the embankment. The west bank (adjacent to Formby Business Park), for approximately 350 metre upstream of Lord Sefton Way road bridge, is being investigated in terms of its structural stability. The embankment profile has a steep riverside slope over this reach owing in part to the close proximity of buildings on the landward side constraining its position. Although there have been no signs of slippage along this section during any of the regular inspections, the initial condition assessment has suggested that it would warrant a detailed investigation, potentially leading to stabilizing works. The report of the investigation is awaited.

In conclusion, I shall refer to a few recent significant planning applications. The redevelopment of the Powerhouse building and site is still being investigated by Council officers and I understand that it will not be possible for them to make a recommendation to Planning Committee in time for its next meeting on 28 April. There has been an application for a four story block of twelve apartments of modern design on a very narrow site at the head of Marsh Brows close. The site is bounded on the west by Formby railway station and car park, and is a close neighbour of two large electricity substations. We opposed the proposal on several grounds, chief amongst them the belief that the building would be much too large for the site and would be completely out of character with the street scene, which it would dominate by reason of its very considerable height and mass. We also complained that the initial amenity area of 160 m2 was unacceptably small compared to the minimum of 360 m2 required by the Council’s own modest guidelines; as a result, a second amenity area of 110 m2 was added, but we continued to complain that 270 m2 was still too small and that, anyway, both areas were of very low quality (the planners concede the areas will need acoustic protection, but they argue the presence of balconies in some of the flats should be counted as compensation for inadequate amenity space!). Regrettably, the proposal has been approved, but subject to a large number of conditions, some of them rather onerous. Finally, there is an application for a building to replace the former children’s home at 86 Victoria Road (the third application for the redevelopment of this site since May 2008). We have criticized its dominant zinc roof with raised seams and its tall narrow stainless steel chimney pots, together with a number of other ill-conceived features. There has been a good deal of opposition from neighbours, some of whom we have assisted with advice on procedural matters. The case is expected to be considered at the next meeting of Planning Committee.

Information concerning the several planning applications on which we have commented is available of the Society’s website

Posted by: Dr Reg Yorke - on: 09 June 2010