Thursday, 29 May 2014

Waste Not: Comments on the Waste Water Strategy Document

The "Waste Water strategy" document to be debated is lodged by the Council of Ministers. It is an example, for once, of real joined up work - the Treasury looking at the finance, Planning looking at the environmental needs, and Transport and Technical Services doing the basic spadework.
It has to be said that this is an excellent report, and the bulk of it is clearly the work of the team of Civil Servants at TTS, who have produced what is a model of detail and clarity. Anyone who simply wants to understand how the Island's waste systems operate, and their history, has only to read this report, where it is all encapsulated with the 109 pages.
The existing sewage treatment plant, as well as being particularly smelly in the Bellozane area from time to time, is basically the same one that was put into operation back in late 1950s for a population of 57,000, modified and marginally extended as time went on, and it really is fast approaching the end of its lifespan. The UV plant was upgraded in 2003 with self-cleaning and more energy efficient units with applied dose monitoring facilities. At present Bellozanne takes flow from a connected resident population of 85,000, which increases to a summer peak population of approximately 102,000.
When it was built, no one could have thought of almost a doubling of the Island population in the summer peak, and the increased demands on the infrastructure. That also leads to odours, and these have been partially mitigated by enclosing areas such as the sludge storage tanks and inlet works, with the air treated by way of odour control units. These works were implemented in 2008 but with limited success to date.
Water consumption can be lowered by the population using less, but an increasing population will always lead to more demands on the sewage system. As the report notes, "any additional loading as a result of an increase in the Island's population... will only result in a deterioration of the present situation."
This means that it is failing in many ways, which are injurious both to the environment, and potentially to public health. As the report notes, it fails "to achieve total nitrogen permit limit, and suffers from extensive biological foaming, a consequence of which is poor removal of suspended solids and lower bacteriological kill from the UV disinfection process". And a survey in 2008 also showed that "approximately 42% of the mechanical and electrical items were in very poor condition."
The existing sewage network needs re-examining as well. The older systems used to mix up ground water with waste water, and that was again fine for a small Island population. Pressure on the systems led to the cavern at Fort Regent, but there is still need for more to be done. At times of heavy rainfall the system is under increased pressure, and on occasion, outfalls of untreated sewage into the sea have taken place. As the report notes:
"In terms of effluent compliance, of particular concern is the fact that the existing plant discharges partially treated sewage, missing out on the secondary treatment process, on a regular basis. This is usually during storm conditions, which generate high flows to the works which are in excess of the full treatment capacity. As a result, discharge of partially treated sewage to the Bay also leads to a risk that public health will be adversely impacted. In 2010, this bypass procedure operated in storm conditions for periods totalling 130 days."
The new system proposed for Bellozane has to comply with the following very sensible criteria. It must be:
-          Flexible, in terms of adapting to potential increases or decreases in population or potential future changes to consent standards;
-          Sustainable, not only in terms of power usage, carbon footprint, etc., but also in terms of its effect on the wider environment;
-          Proven, in that the success of the process technology in achieving the required level of treatment is well known, widely used and understood; and
-          Affordable, not only in terms of capital cost, but also in terms of operating costs
As it has been reported, the States want to spend £75 million on improving the system. But against this must be the consideration that relatively little has been done to improve the system and bring it up to modern standards, as well as dealing adequately with the demands of an increased population.
Two Chief Ministers have come and gone, and I noted on my blog - back in 2008  -the Medical Officer of Health's report which called for:
"the early formulation of an Islandwide liquid waste strategy to determine the appropriate level of improvement and extension to the mains drainage network, along with an appropriately sized and located replacement for the Bellozanne sewage treatment plant". In January 2012, TTS were saying (on BBC News) that the works were 50 years old and " outdated and not up to current standards for pollutants, saying a new treatment works would be needed in the future."
Contingent planning has taken account of increases in the population, and also adjusted for a seasonal increase due to tourism, visiting friends and migrant workers. The new plant is looking at a population of 118,336 estimated for 2035, which includes these extra numbers, estimated at around 19,149 for a maximum adjustment. As the report notes, "it is considered advisable to provide flexibility in the design such that 118,000 is not an absolute limit but can be expanded with minimal cost in the future." Of course population measures in place may limit that, and I hope they do,  but it is surely prudent to allow for future growth rather than requiring the patchwork modifications of the current plant.
Another factor is climate change, which is another reason for a better sewage works, and also for looking at improved pumping systems, and waste water separation. The report notes that:
"The potential for climate change impacts on the Jersey sewerage network has not been fully assessed. It has been assumed that in common with the southern part of England climate change will lead to increases in the magnitude of storm events within the Strategy period. This will increase the waste water flows to be handled by the network, the pumping stations, the overflows and the STW. In the absence of detailed modelling of the assets, a simple general allowance for upsizing the assets as they are maintained / renewed has been made of 5% of the projected maintenance cost."
The sewage systems themselves need checking as an initial assessment has indicated that a substantial proportion of the existing sewerage network is already at capacity. This is being addressed by a scientific study of the patterns of flow. As the report notes:
"A programme is currently being implemented to investigate, locate and resolve the infiltration / inflow problems across the Island. By using a combination of pumping station telemetry data and in-sewer flow monitors, a systematic investigation is being undertaken to identify the location and severity of the problem so that suitable remedial measures can be carried out."
Back in 2008, when I was looking at the sewage system, I noted that "Biogas production from sewage sludge treatment, via a process called anaerobic digestion, is already a well established means of generating energy in the UK."
It was good to read that the proposed new plant incorporates this into its plan:
"The ongoing project to replace the sludge treatment facilities involves enhanced sludge treatment achieved by a pasteurisation process followed by anaerobic sludge digestion. Methane gas produced during the treatment process will be utilised for heating of the sludge and power generation to meet approximately a third of the power requirements for the new Sewage Treatment Works"

It appears that the Environment Minister, Deputy Duhamel, would prefer some alternatives, and, time allowing, I will look into those. It should be noted, however, that the proposed new sewage treatment facility does accord with EU regulations regarding the environment with regard to treatment and disposal of waste matter. It is an environmentally sound choice, even if some dissenters think there would be even better choices to be made.
As this States gradually comes to an end before September, and the run up to the October elections, it is perhaps worth looking at what the present Council of Ministers have achieved under Ian Gorst, and which was not achieved, and perhaps delayed or ignored under the somewhat slack leadership of his predecessor.
Of course, there have also been failings, not least with the Electoral Commission and Referendum, and virtually anything from Economic Development seems to be hedged around with the same vagueness and management speak that Jim Hacker of "Yes Minister" would be proud of.
But there seems less of a fortress mentality that I noted in the past, and more willingness for Ministers to work with backbenchers to agree propositions such as Montfort Tadier's recent one on Rental Housing Standards, working with the Housing Minister.
The Waste Strategy is certainly a fine legacy to present to the outgoing States. I was hugely impressed by it, as a model of clarity and facts.

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