Wastewater Forum


Meeting 25th March 2015

Please note that for older reports some links will be to sites that are no longer active.

This was the Forum’s 55th meeting and the last to be chaired by Andrezj Nowosielski who is leaving the Environment Agency to join an organisation called Water and Sanitation for the Urban Poor. Andrezj has been an enthusiastic chairman; he will be succeeded by Barrie Howe, also EA. Again the Forum met in CIWEM’s HQ, 106-109 Saffron Hill, London.

Reports from topic leads

Flow & Quality - Oliver Grievson, Anglian Water

- started an e-book on wastewater flow measurement including dry weather and flow to full treatment. Contractors still install flow meters very badly, an issue of which the MCERTS Steering Group is aware. The universities of Sheffield and Loughborough are cooperating on wastewater flow measurement (see also 6th March 2014).

Catchment Scale Impacts - Mike Hutchins, CEH [for Richard Williams]

- CEH has been looking at pollutants (principally 75 pharmaceuticals) that have a wastewater source and a catchment impact. Attenuation downstream of discharges proved very important due to a combination of dilution and partition to the sediment.

- WorldQual model has been used to assess E. coli attenuation.

- A study in Belgium of a 1600 km2 catchment that has 8% impervious surface has 300 monitoring points measuring chloride and nitrate.

- an artificial neural network is proving superior to correlation models for understanding BOD is waters at national scale

- as BOD Consents decrease (become more stringent) the accuracy of the test becomes more of an issue; tryptophan-like fluorescence has been used to measure Biological Oxygen Demand & organic pollution; WERF has found a consistent ratio of TOC to BOD, inlet to outlet.

New Drivers and Legislation - Andrezj Nowosielski, EA

- AN is assembling a network of people with knowledge of this topic.

- The attitude to flow measurement has been tightened since it came to the attention of OMA (Operation and Monitoring Assessement).

- A change to Freedom of Information legislation requires faster response.

- Dangerous substances legislation is being revised as will Shellfish Waters

- Bathing Waters regulation will be more stringent when the season opens 15th May 2015.

- The EC thinks that the implementation of water legislation has been good but has concerns about: - EA is researching - Watch list of substances

- There is interest in introducing virus standards; shellfish water are the most likely first candidate; the USEPA is also interested in this topic and developing robust methods of test.

A roundup of members’ research included the following:

Mike Hutchins, CEH [for Richard Williams]

- CEH has been commissioned to produce living with climate change report cards for urban hydrology

Gordon Jones – FWR

- FWR is taking the lead in three catchment studies with some funding from EA.

- Regarding ROCKS (Reviews of current knowledge):

Andy Eadon – Regional Flood & Coastal Committee

- There is still a need for an urban runoff model that does not conflict with the wider catchment models.

- AE is encouraging RFCC to research runoff from non-urban areas. More of the funding for flood defence is coming from local levies so more attention is being directed to local issues than catchment management and control of rivers is being lost. Habitat creation has been a victim of austerity cuts. Resilience is being increased at the behest of insurance companies.

Simon Tait – Sheffield University

- Completing an EU Innovative Energy Recovery Strategies in the Urban Water Cycle INEERS

- STREAM is the Industrial Doctoral Centre (IDC) for the Water Sector funded by the Engineering and Physical Sciences Research Council (EPSRC) and companies who sponsor research projects. It is coordinated by Cranfield University and includes Imperial College London and the universities of Sheffield, Newcastle, and Exeter, the programme enables talented researchers to develop their skills and careers, while obtaining an Engineering Doctorate (EngD) or PhD degree.

- EPSRC has a call on ‘big challenges’ Sheffield hopes to research biofilms and the potential of synthetic biology in biofilms; could they be used to modify hydraulic resistance and could they repair cracks?

Andrezj Nowosielski – EA

- The EA is still updating its R&D programme.

- What is the correlation between rainfall and bathing water compliance/quality?

Technical Presentations with members of CIWEM’s Wastewater Management Panel

Nutrient sources and fates in rural streams; can agri-environment schemes improve water quality? - Mike Bowes, CEH

This described a farm-scale experiment into the effectiveness of grass margins, which earn agri-environment credits, for reducing phosphate in streams. The site is on clay textured soil in Buckinghamshire. The experiment compared 6m wide margins with 6m margins sown with phosphate accumulating plants and with 30m margins with phosphate accumulating plants. The largest phosphate loss from fields is “particulate-P”, which is phosphate attached to soil particles, the objective of the margins is to trap soil particles and filter the runoff water.

The design comprised 4 replicate treatment blocks. The width of margin had no effect on the concentration of soluble reactive phosphate measured in the stream and neither did the seed mixture, which indicated that 6m was adequate. However, there was an unexpected finding; even in this rural area with no conurbations upstream, 200 mgSRP/L (soluble reactive phosphate) or more was found at some of the blocks and this was accompanied by boron, which showed that septic tank and misconnection contributions overwhelmed the diffuse inputs from farmland (perborate is a whitener in some detergents). Reducing sediment runoff into streams is useful but grass margins cannot solve the SRP issue when there are other, greater, hitherto unrecognised sources. By coincidence, Bob Middleton from Natural England told the CIWEM Annual Conference about the Catchment Sensitive Farming programme, which he described as “highly targeted and focused” but septic tanks and misconnections are not included in the targets. They might make five or more visits to a farm but until now have not checked to see whether these “stable doors” are open. It would be very useful if the results of CEH’s work caused NE to amend the focus and targeting of CSF.

Intelligent Wastewater Networks - Oliver Grieveson, Anglian Water

Oliver’s report was based on the CIWEM “Value of Intelligence in the Wastewater Network” conference that was held on 18th February. It was a sell-out with a waiting list. Most WaSCs are considering smart sewerage. Commercially available FDT Flow Detection Transducer for CSO & SSO Event Duration Monitoring and BDT Blocked Sewer Detection Transducers are increasing the practicability. Barcelona, Berlin, Copenhagen and Paris are four examples of smart sewer networks; Paris operates its sewerage as six networks. They have found that actively managing sewer weir heights, etc. to flush sediments reduces CSO activations at 25% of the capital cost of building tank sewers but would this strategy be compatible with the UK’s very prescriptive approach to consenting CSOs? There were signs for hope that the UK’s “culture” around wastewater management might be evolving but depressing signals about how far it has to go. AMP6 and Totex might herald more post-project appraisal because the name of the game will change from just building stuff to managing the businesses for best whole life cost but old cultures die hard.

The next meeting of the Forum will be 19th June 2015