F.A.Q

The IWMF as a whole is using less water than anticipated because the proposed paper pulping plant, which has not been built, would need a much greater supply of water and would also need to extract water from the River Blackwater. The facility uses the equivalent water to ~500 houses. Although this initially sounds a lot, it is relatively small compared to the thousands of houses that have been built in the area since the IWMF received planning permission 17 years ago.

Yes, Indaver is complying with all planning and permitting conditions.

The water is used as boiler feed water. This has to be of a very high quality and is further treated on site to make it as a pure as possible. Other water needs on site do not use mains water. The ash quench system, for example, uses captured rainwater that falls on the open areas of the plant and is captured in an underground tank.

Indaver is aware of concerns regarding water supply in the local area. Rivenhall IWMF has also experienced challenges with water availability, and we have been in contact with Anglian Water to identify a solution. To reduce reliance on the local supply network, we have taken a number of steps within our own facility, including installing temporary water storage tanks on site, scheduling peak water use to night-time hours, and bringing water to the facility by tanker when required. We have previously invested in buffer storage and continue to explore options that provide greater water supply resilience for the site. We are working with Anglian Water to identify a long-term solution and will continue to take measures that minimise demand on the local water network wherever possible.

The Rivenhall plume abatement system uses Best Available Techniques to prevent a visible plume. Like any complex piece of it equipment it requires testing and commissioning to ensure it can be effective in all climatic conditions. The information previously approved under condition 17 of the planning permission for the Rivenhall IWMF, prior to Indaver taking control of the site, did not contain any information regarding the commissioning or calibrating of the plume abatement equipment before it was brought into use. Working alongside Essex County Council, Indaver have sought to rectify this omission by submitting a non-material amendment. The non material amendment allows the submission of  management plan which explains likely visible plumes over the testing period. In order to test in all climatic conditions the management plan covers a testing period up to December 2026. 

The Rivenhall EFW  facility has a vacuum unit which moves clean steam through the process from boiler to turbine and back again. There are two parts of the system. A start up ejector which vents steam to atmosphere and a holding ejector which does not.  During commissioning the start up ejector is used heavily until all parts of the plant are running efficiently. After all elements are commissioned the start up ejector should only be used at plant start up which routinely occurs once a year. During normal operation the holding ejector is in use and no steam is vented to atmosphere from this system. In addition to this steam may be visible on occasion from roof vents during start up. The plant is due to finish commissioning in April 2026. 

Anaerobic Digestion (AD) is a natural process where microorganisms break down organic matter in the absence of oxygen, producing biogas and a nutrient-rich digestate. An anaerobic digestion plant is usually used to process organic matter, predominately food waste.

In Essex, food waste collected from households is recycled via anaerobic digestion. Since a change of contracts ECC, WDA food waste is now taken to a facility in Dagenham. There is also an operational plant in Halstead, although this is not currently being used by ECC.

Indaver has planning permission to build an AD facility and monitors the market closely to look for opportunities as the need arises.

Indaver is an organisation that values sustainability. We have planning permission to build a recycling facility at Rivenhall, but this must be based on need and it would be irresponsible to build a facility that was not required. Our current planning application seeks to amend the use of the permitted MRF to also accept bulky household waste, a facility which is needed in Essex.

The recycled plastics market is facing a recession across Europe. Our competitors are closing plastic recycling plants because of reduced demand, with a Kent recycling facility closing in August 2025, a Sunderland facility earlier in the summer, and a Bristol facility in 2024.

In issuing the EfW plant’s Environmental Permit, the Environment Agency presented its decision summary relating to the potential impacts of the plant on human health and local air quality, which states:

Our conclusion is that we consider the proposed facility is unlikely to contribute to any breach of the relevant air quality standards for human health and the environment…

For the proposed design and operation of the incinerator plant, we believe that emissions of particulate matter (PM10 and PM2.5) have been demonstrated to be insignificant…

We are confident that the stringent controls imposed by UK and European legislation coupled with effective day to day regulation will safeguard human health in the locality of the facility. 

Yes. In 2024, around 500,000 tonnes of waste from Essex was landfilled or exported outside of the county and even abroad to energy-from-waste facilities on the continent.

No. All trucks entering the EfW plant will use the access road via the A120. Although the site road crosses 2 local roads, the bollards in place make it impossible for a truck to turn onto the site road at those points. HGVs are not permitted to use the Woodhouse Lane entrance. All trucks must be weighed on arrival on the weighbridges at the main site entrance.

If the A120 was to be closed for any reason, then the waste trucks cannot enter the site via any other route. We have a contingency plan in place to contact all of our customers and cancel further deliveries if this were to happen. The maximum number of 202 trucks per day amounts to only 2% of the traffic currently using the A120. All of the waste coming to the IWMF is already using the road network to travel to other facilities, so Indaver are not adding any extra vehicles or their emissions to the roads.

No. All of that waste formerly went elsewhere – some of it over to the continent for disposal. Some waste now undoubtedly has a shorter journey.

Around 20% of the volume of the waste will remain as non-hazardous ash. This will be processed to remove metals for recycling and the remainder will be processed into secondary aggregate for the construction industry.

No. The EfW plant will incinerate residual waste left over after recycling.

When disposing of household waste, if cardboard or plastics are wet or soiled in any way, they cannot be recycled as they are considered contaminated. This waste still needs to be disposed of safely and as efficiently as possible.

Investment in new or expanded EfW plant’s only take place in well justified cases, in full respect of the waste hierarchy. EfW’s are sized appropriately to cope with demand and are not a replacement for recycling, the plants simply compliments these efforts by reliably treating waste that cannot be recycled.

The EfW plant will produce around 500,000 tonnes of CO₂ per year. The alternative is to send the waste to landfill where it degrades and produces methane, a much more potent greenhouse gas. Landfill produces an additional 200kg CO₂ equivalent per tonne of waste compared to incineration. This means that treating the waste in the Rivenhall  EfW plant actually saves the equivalent of 120,000 tonnes of CO₂ emissions each year.

The circular economy encourages the elimination of waste and the continual use of resources. Unfortunately, as a nation, we still produce a lot of waste (much of it non-recyclable) that needs to be treated.

Nonrecyclable waste needs secure and reliable treatment to avoid further pollution. Energy from Waste facilities create energy from these contaminated materials and black bin waste that would otherwise be sent to landfill. Plants like the Rivenhall EfW also offer the highest possible recycling rate of the metals that occur in the residue, contributing to a more resource-efficient economy where as many valuable materials are kept in use for as long as possible.

Indaver will be preserving the history of the site by restoring and refurbishing the grade II listed Woodhouse Farm and Brewhouse. The proposed plans are to turn these spaces into a visitor centre and museum, we’re considering various options to make use of the other buildings on site.

Although the EfW facility is designed to prevent waste odours from escaping from the building, depending on the weather there can be an odour from the trucks bringing waste to the site. For the most part this is quite transitory, but can be noticeable if the truck is stationary for any length of time. With the recent roll-out of separate food waste collections across households in Essex, the food waste that is the main cause of this odour in general waste collections should significantly reduce over time.

Unlike the pollution abatement system, which captures pollutants, the plume abatement system does not capture steam. A steam plume is formed when the hot, moist air from the stack hits the cooler air above and condenses into water vapour – exactly the same as when a kettle boils. The plume abatement system re-heats the plume to 230^oC so that it is more buoyant and therefore disperses faster, and so that it also takes longer to cool down so it condenses more slowly. The net effect of this is that by the time it condenses into steam it has spread out far enough that it is no longer visible.

The efficiency of the plume abatement system is very dependent on ambient air conditions, making a visible plume more likely in damp, still air. A visible plume is not an indication of pollution however – it is merely steam.

Source separation at kerb side is the most effective way to ensuring what comes to the energy-from-waste facility is non-recyclable. Based on the recent Braintree waste composition analysis, it was estimated that nearly 40% of the waste contained within the grey bin could have been recycled by using the current kerbside recycling options available, and only 1/3 of food waste is being correctly disposed of in the food caddies. Education of the public is the key to ensuring that recyclable waste does not end up being incinerated.