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Effluent treatment - A boardroom issue

Effluent treatment plants

Rich Matthews explains why boards should understand more about effluent treatment in terms of business compliance and risk.

Effluent treatment plants (ETPs) can often be overlooked and underinvested in. Whilst production pressures and product innovation usually top the investment needs; it is the effluent plants that can attract significant business risk if not carefully considered. The ETP plays a critical part in day-to-day operations and can be impacted on by a variety of product decisions; from production throughput and changes in product type through to potential seasonal impact of demands.

Whilst there can be many diverse input stresses placed upon ETPs, there are normally limited disposal routes available; direct to sewer, direct to watercourse or tankered offsite. Each presents its own risk, cost, and sensitivity to business operations. However, it is broader issues such as the availability of the ETP for production, environmental compliance and energy consumption that present some fundamental risks to the business.

The attention that should be applied to the effluent treatment plant from a boardroom perspective should focus on resilience. There is a clear business risk with the ETP operation and performance, therefore there is a need to consider contingency planning as an essential part of the process, with the aims to both be more agile in managing waste streams and to improve business efficiency without increasing risk.

Effluent treatment selection

A company’s chosen treatment route can depend on several factors such as the volume, effluent characteristics, space available on site, and the available treatment capacity at the local waste water treatment works. Furthermore, there may be considerations in the reuse of treated effluent or waste product for regeneration; both may attract additional investment but offer a return or a step change in overall plant efficiency. 

The robustness and flexibility of the ETP are essential considerations to ensure that the plant is adequately sized for the investment but equally sufficient for the fluctuations in production types, volumes and cyclic or seasonal activities. Whilst certain waste streams will attract particular treatment needs, it is the discharge routes that can have the greatest influence on processing needs and waste stream outputs.

Direct to sewer solutions will attract the consideration of trade effluent consents; applying Mogden charges from the receiving waste water authority. These are largely charges based on volume, solid concentrations and chemical oxygen demands (CODs); using a consistent methodology.  Further, specific constituent parameters may also be applied given the nature of the effluent type and the capacity of the receiving wastewater works. With these consents being monitored by the receiving water authority; it places a significant emphasis on the compliance of the plant.    

When discharge to watercourse is being considered, there are increased levels of scrutiny applied through permitted discharge criteria. These will vary depending of the status and size of the receiving waters but treated water quality and consistency are critical to compliance and relative to the business risks. 

Whilst the remaining discharge option for tankering doesn’t attract as much permitting by external authorities, there will be limitations on volume from a commercial and logistic perspective. There may also be restrictions on what waste type can be accepted and variations in tankering costs will reflect this.

Production strategy

The production line can have a profound effect on both the volume and type of effluent waste that the ETP receives. As a result, it will influence disposal routes, costs and compliance. It is a critical responsibility for the boardroom to recognise the impact of production changes - be these to the type of product manufactured or the volume due to seasonal variation - on the compliance needs for the ETP.

Despite this close link between product strategy and effluent costs, when we surveyed plant managers/production directors in leading UK food and drink operations, 46% overall (rising to 48% of those operating multiple sites), said that those involved in product development just don’t consider the effect of a new product on effluent volume and characteristics – something which marketing and operations directors need to remedy.

Working closer with the production line to understand fluctuations in flow and load; combined with the robustness of the ETP is critical to managing the business risk. The production strategy should seek to understand these risks and issues so the company is able to implement a compliance plan to cover the ‘what if’ situations for the production plant.

Viewing the ETP as an extension of the production line is a critical perspective and allows the business to focus on pinch points, remedials and preventative actions to maintain the business risk at an acceptable level.

Implications of getting it wrong

The risk of non-compliance presents significant business risk. The ETP or waste stream routes will be one of many environmental permitting considerations across a production site. Since the re-introduction of the Environmental Sentencing Guidelines (2014) additional awareness and focus has been placed on environmental permitting across a variety of sectors.

The sentencing guidelines established the principle that fines should be proportionate to the degree of culpability as well as the size of the company - i.e. equal financial pain for all, irrespective of a company’s size.  

With some significant cases now being pursued through this, the judgements are seeking to take this process a step further by establishing the following principles in environmental law:

  • It should not be cheaper to offend than to take appropriate precautions
  • Shareholders need to understand that the environment is to be treasured and protected, not poisoned
  • Significantly sized fines will get that message across

In addition to this, the Environmental Undertakings that are now being used as a vehicle to instigate appropriate behaviours have seen a number of high profile companies pursued such as Thames Water, Wessex Water, Carlsberg and Tesco Distribution having enforcement action taken against them (publications November 2018).

Furthermore, there are the pressures that are being applied by the wastewater authorities in response to a non-compliance. “It’s important that we prosecute companies which seem to believe that legal limits on chemical release don’t apply to them. We have a duty to protect our treatment works, our customers and the environment and big fines such as this send out a clear message to any business contemplating doing something similar.”

Not only are there the financial and commercial aspects to the business, but a major pollution incident will adversely affect a company’s reputation locally, nationally and even internationally – something it may take many years and many millions of pounds of marketing spend to recover from.

Clearly, the implications from some cases to date are that companies now have little choice but to ensure they adopt best environmental practice or face the risk of incurring greater costs by not complying. Equally there is consideration of ensuring that contingency planning is in place to provide the necessary resilience.

Developing resilience strategies

Clearly the degree of complexity and sensitivity within the waste effluent permitting will influence what resilience needs to apply to the process, but fundamentally it needs to be considered as part of contingency planning in the operation. 

Seeking a more agile investment approach is one way of implementing a resilience plan. The use of modular temporary kit is becoming of increased interest for its agility in installation and being easily deployed for seasonal loads and capital maintenance where flexibility is required.  This kit not only allows for proactive planned maintenance to take place but reduces the impact on the production line; maintaining the wastewater streams and compliance.

A little like Lego, companies are bolting together pieces of kit which have been manufactured off site, to tackle their effluent challenges. This approach is enabling more rapid innovation in the area, reducing the capital costs of systems, minimising disruption on site and giving companies greater treatment agility. If circumstances change, or new consent criteria are set, the supplier can come back, and easily modify the system. This is rapidly becoming a very attractive solution to companies operating in an increasingly uncertain and changing environment.

Further benefits can be achieved through optimising plant performance; aligned to compliance / resilience planning.  As an example, we worked with Dartmouth Foods to solve a wastewater problem and, at the same time, reduce its energy costs. The FOGs produced at its meat processing plant in South Devon were putting such a large strain on the local sewerage infrastructure that it was asked by the region’s water company to install a system for FOG removal.  We installed a combination of a mix tank and a packaged lamella DAF unit, designed specifically to remove suspended solids. The system can treat 1.5 m3/hr, neutralising the effluent before removing the FOG, TSS and associated COD. The removed fat is then pumped to the mix tank where it is combined with other sludges from the site before being pumped into its anaerobic digestion facility where it is used as feedstock. 

Aligning operational flexibility in modular ETP solutions provides an agile solution to managing the business risk on compliance but equally offers the opportunity to enhance efficiency in the management of the waste streams.


A myriad of board decisions can affect a company’s waste water treatment strategy, but it is essential to recognise the change in outlook required to manage through resilience approaches. Developing the resilience strategy is primarily about recognising the risk and having access to and implementing appropriate contingencies. The primary assessment is to determine if the existing ETP is sufficiently flexible for the production needs of the business and the degree of capacity to meet fluctuations and shifts in patterns. Compliance is a fundamental consideration for the business, and having means to implement responsive treatment solutions is an essential part of the contingency planning process.

A food manufacturer’s ability to respond to market conditions, grow, increase throughput, minimise energy bills, reduce other costs, innovate, maintain brand reputation and meet environmental obligations are all intrinsically linked to the way it manages effluent treatment.  While of course production heads and plant engineers will be the main decisionmakers in this area, every board member should be interested in their company’s waste treatment operation. Treatment plants may be out of sight, but they must not be out of mind when companies are planning their production and investment priorities for the year ahead.

Rich Matthews

General Manager of Siltbuster Process Solutions

Siltbuster Process Solutions works with major names such as Premier Foods, Chivas Brothers and Heinz. It provides complete process solutions in areas that typically include: the need for additional treatment capacity to ensure discharge consent compliance, peak season surges in effluent production, reducing Mogden charges, and exploring potential temporary or permanent solutions to these issues. 


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