FAQs - Peel

The Planning Inspector when reviewing the Glenfaba House proposal concluded that there was insufficient evidence to prove that there were not more suitable sites for a treatment works with lesser environmental impact.

The House did not require planning permission for demolition and had been structurally assessed as unsafe, requiring demolition.  We worked closely with Manx National Heritage to document the building and site prior to demolition.  The site will be sold at a future date.

We went back to the beginning and reviewed over 40 potential sites that had been previously identified in feasibility studies or had been proposed during a public call for sites. The pump away to Meary Veg option was also reviewed.

A rigorous ‘coarse screening’ process was completed against criteria such as space, land zoning, proximity to residential areas, ecology and other factors which led to the selection of a small number of options which were looked at in more detail in order to determine the preferred solution. A concept design (comprising site layout and pipeline routes) for each option was created and a desktop environmental review completed (including carbon footprint calculations) to allow a further ‘fine screening’ assessment to be undertaken, resulting in each option receiving a ‘quality’ score. Each was then costed with the ‘whole life costs’ developed over periods of 25 and 50 years. The cost and quality scores were then combined on a 70:30 quality: cost ratio (also undergoing a sensitivity check at 50:50) to ensure the best solution was chosen, not necessarily the cheapest.

This process resulted in the preferred site being the fields adjacent to the Peel Power Station.

The future of the Glenfaba House site is currently being considered.

IRBC (Integrated Rotating Biological Contactor) equipment will be used at Peel, as it is throughout the Island at 13 other locations. This is a tried and tested process used extensively in the UK and Ireland.

The process used at Meary Veg is slightly different ‐ it is an aerated ‘activated sludge’ process. Some of the IRBC treatment works produce effluent of a significantly higher quality than that of Meary Veg.

Numerous studies have been completed that all conclude that the regional approach is both cheaper and more sustainable than connecting into the IRIS network.

The total length of construction programme is 34 months.

Processing sewage can lead to the production of odour, and so we are taking steps with the provision of odour control equipment to minimise this risk.

There are a number of treatment processes available, the final design/specification will result in the most effective treatment for the site being implemented.

Some earlier sites did not include odour control facilities and these are now being introduced as a retrofit following public feedback. The IRBC system provides a covered plant which lends itself well to the provision of odour control.

There is no plant within the works that produces high levels of noise. Any noise created by plant will be attenuated as required. We have many IRBC sewage treatment works in very close proximity to residential properties and do not receive complaints with regard to noise.

No ‐ The site will operate automatically at night in darkness. Movement activated (PIR Controlled) lighting necessary for out‐of‐hours emergency maintenance activities will be used. PIR movement ‐ activated external security lighting may also be provided to ensure the safety and integrity of the facility.

No, given the nature of the works no pathogen containing aerosols will be produced.

It is envisaged that 2 tankers will visit the site each day, 5 days a week. There will also be daily visits from operational staff in small vans.

Access to the site will be from a new private road running directly down from the A27. This will be one of the first elements of the works to be constructed to ensure large plant will not need to travel through Peel. The site will be accessed via the A27 through Patrick.

Combined Sewer Overflows (CSOs) are a necessity on the Isle of Man (as they are in the UK, Europe and around the world) due to the combined nature of our sewerage network. This results in large amounts of surface water entering the system which is designed to allow the discharge of dilute ‘storm sewage’ through CSOs when the infrastructure is overwhelmed to prevent the flooding of property during heavy rainfall. Whilst many schemes have been undertaken to remove surface water and infiltration from the sewer network, it is not financially viable to retrofit a fully separate system, and so these discharges are a key part of providing an economical and effective sewerage network.

The infrastructure proposed at Peel will include a combined storm overflow at the Promenade pumping station which will be constructed to modern day standards including 6mm screening to remove all solid particles before being discharged with the works final effluent through the existing outfall .

The works will provide a minimum of ‘Good’ quality bathing water as required by the Isle of Man’s Water Pollution (Bathing Water Standards and Objectives) Scheme 2021. Modelling predicts that the impact of sewerage discharges will be very close to providing ‘Excellent’ bathing water quality, and it is the frequency of storm discharges which is the potential barrier to that achievement. It should be noted that sewage discharges are not the only discharges that impact on bathing water, with animal faeces, agricultural runoff etc. all potentially having a detrimental impact on bathing waters.

The bathing season is currently defined within legislation. Whilst we acknowledge that the bathing waters are used year round, at present there are no guidelines on bathing water standards outside of the defined season, and no evidence that having the UV switched on during the winter would provide any benefit.

Blue Flag Status requires some 40 factors to be addressed, of which bathing water quality is one. It requires ‘Excellent’ bathing water quality to be achieved. Should Blue Flag Status become a realistic ambition for Peel beaches and future monitoring indicates that storm spills are preventing the ‘Excellent’ standard being achieved then there are surface water separation schemes which could potentially be undertaken to reduce the amount of surface water entering the network.

The current plan is for the leachate from the Raggatt to be pumped to the new Peel wastewater treatment works. This will involve the construction of a small pumping station at the Raggatt along with the installation of a pipeline to the new works. It is planned for the leachate to be processed through the wastewater treatment works which is expected to remove a high percentage of PCBs. The PCBs removed will be captured within the sludge which will ultimately end up being processed at the Energy from Waste Plant. The receipt of the leachate at the new works will be subject to DEFA issuing an appropriate Discharge License

IRBCs will be part of a routine maintenance programme and major parts may need to be replaced on a 20-year cycle.

Site surface water run-off areas are zoned to ‘clean’ where they will be discharged to the river or as ‘foul’ where they return to the inlet works for treatment. Attenuation tanks are being constructed to ensure the discharge flow rates are controlled.

Unfortunately the underlying ground conditions are unsuitable for ‘soak-away’ methods.

The holding tank at our Peel Promenade pumping station is as large as it could possibly be given the surrounding buildings. It has a volume of over 1,800m3 and in terms of flows into the system it is adequately sized in order to limit the number of discharges to an acceptable level as per the Isle of Man’s Bathing Water Standards.

The sewage system in Peel is predominantly a combined system built by the Victorians, where surface water and foul sewage were conveyed in the same pipelines, and indeed the rain water was used to flush the foul water into the sea. This makes it very tricky to separate out the storm water and as such we have no real choice other than to manage the large quantities received.

Various surface water separation schemes have been undertaken in the past, and there may be more opportunities to do the same in the future, but most of the simpler, more economically viable schemes have been completed. Through our sewer rehabilitation programme we are reducing the amount of infiltration entering the network by maintaining and improving the condition of our sewers.

The initial works provides 7 IRBCs for the current population with headroom for short term population growth. There is space for a further two more to cater for expansion to 2050 and beyond.

The structures constructed as part of the treatment works are not suited for accommodating bird and bat boxes. Following a site review by the appointed Ecologists a variety of bird and bat boxes (12 total) will be erected on existing trees at the site boundary  

The site is partly shielded by hills so solar input is less than optimum; there is insufficient head to use either flow in the River Neb or treated effluent return flow to generate power as it is only sufficient to return to the outfall.

The access road and treatment works occupy 2 fields. The remaining land will be owned by Treasury.

We have worked closely with Manx National Heritage during the Planning process. From a review of the ground investigation it is unlikely there are any areas of archaeological interest within the site. The Contractor has, however, been given a watching brief and MNH will be contacted following any excavation work that warrants further investigation.

Whilst the planned Contract Completion date of the whole works is Spring 2028 we have tasked our contractor to bring elements of the works on line as soon as possible. As such we are aiming to have primary treatment (screening) on line late next summer with partial biological treatment (4 no. IRBCs) ahead of the summer 2027.

Full completion of all of the process works will be early 28 and the whole scheme including landscaping etc in the Spring of that year.