Northumbrian Water Group (United Kingdom)

This report presents Frigate, a novel astronomical dataset comprising still-frame images of a section of Low Earth Orbit (LEO), collected by ExoAnalytic Solutions Inc., a commercial space situational awareness (SSA) provider using ground-based optical systems. Datasets of this kind are rare and typically inaccessible to most stakeholders. Through agreement with the company, the images were collected and prepared for use in machine learning and computer vision tasks related to SSA. The raw images contain lens glare artefacts, vignetting, and outer-region degradation. To address this, we additionally release a lightly processed version of each image featuring artefact removal, background subtraction, and sharpening. Usage notes describe optional downstream techniques including stacking, streak detection, and automated annotation. Given the lack of publicly available space surveillance data, this dataset represents a valuable resource for satellite tracking, orbital debris detection, and astronomical computer vision. The dataset described in this paper is wholly owned by ExoAnalytic Solutions Inc. and was released to the research team through mutual agreement of the benefits of its processing and application to the domain. All data and code are openly available.

Abstract Raw water transfers (RWTs) are a globally occurring freshwater invasion pathway. Recently, the need to better understand the invasion risk posed by RWTs and develop pathway management strategies has been recognised. However, as a complex and challenging pathway to study, few direct investigations of RWTs have been carried out previously, and a detailed understanding of pathway activity is currently lacking. We therefore carried out a preliminary investigation of three separate enclosed RWTs in the northeast of England to obtain direct evidence of species dispersal. In total, viable specimens of 24 different species, including the non-native Crangonyx sp. and New Zealand mud snail (P. antipodarum) were dispersed, though the introduction capacity of each RWT varied substantially. This study sheds light on the role of RWTs in the secondary spread of diverse species, and demonstrates that different pathway characteristics may influence the species introduction capacity of individual RWTs. The study also highlights that given the complexity and variation inherent within the RWT pathway, risk-based approaches to pathway management may be inefficient for meeting this global management challenge.

High levels of organic matter in drinking water catchments are a hazard as there is a known correlation between the presence of organic matter and the formation of trihalomethanes (THMs) during the chlorination stage of water treatment. Organic matter is quantified through the measurement of dissolved organic carbon (DOC) in water.  THMs are potential harmful for human consumption and regulated in drinking water standard, therefore additional chemical loads are required in water treatment to removed THMs which is costly for water companies. Temperature is also known to have a correlation with the formation of THMs during chlorination and the presence of DOC in catchments, meaning this hazard may increase in the future with the predicted changing climate. This study investigates the potential to proactively manage DOC within a drinking water catchment before drinking water treatment to reduce the risk of THM formation during chlorination. The study focuses on a specific catchment in Northumberland, UK, which includes a reservoir that feeds directly into a drinking water treatment plant. A yearlong monitoring scheme is currently being carried out to discover the dynamics of DOC fluxes throughout the catchment and establishing the pathways and sources of DOC loads. Results so far show that for the main tributary to the reservoir DOC loads vary from 65.01Kg/day in normal conditions to 14402.24kg/day in high rainfall, storm conditions. The data collected is being used to determine relationships between DOC load, land use, land management and climate. These relationships will later be utilized in a model which will be used to simulate various scenarios including some future climate analysis. The final aim of the study is to produce a catchment management plan and business plan considering potential DOC load management methods, stakeholder involvement and scenario analysis.

Abstract The passive, ambient sound above the water from a river has previously untapped potential for determining flow characteristics such as stage. Measuring sub‐aerial sound could provide a new, efficient way to continuously monitor river stage, without the need for in‐stream infrastructure. Previous published work has suggested that there might be a relationship between sound and river stage, but the analysis has been restricted to a narrow range of flow conditions and river morphologies. We present a method to determine site suitability and the process of how to record and analyse sound. Data collected along a 500 m length of the River Washburn during July 2019 is used to determine what makes a site suitable for sound monitoring. We found that sound is controlled by roughness elements in the channel, such as a boulder or weir, which influences the sound produced. On the basis of these findings, we collect audio recordings from six sites around the northeast of England, covering a range of flow conditions and different roughness elements, since 2019. We use data from those sites collected during storms Ciara and Dennis to produce a relationship between this sound and river stage. Our analysis has shown a positive relationship between an R2 of 0.73 and 0.99 in all rivers, but requires careful site selection and data processing to achieve the best results. We introduce a filter that is capable of isolating a river's sound from other environmental sound. Future work in examining the role of these roughness elements is required to understand the full extent of this technique. By demonstrating that sound can operate as a hydrometric tool, we suggest that sound monitoring could be used to provide cost‐effective monitoring devices, either to detect relative change in a river or, after more research, a reliable stage measurement.

Bioelectrochemical systems (BES) have the potential to deliver energy-neutral wastewater treatment. Pilot-scale tests have proven that they can operate at low temperatures with real wastewaters. However, volumetric treatment rates (VTRs) have been low, reducing the ability for this technology to compete with activated sludge (AS). This paper describes a pilot-scale microbial electrolysis cell (MEC) operated in continuous flow for 6 months. The reactor was fed return sludge liquor, the concentrated filtrate of anaerobic digestion sludge that has a high chemical oxygen demand (COD). The use of a wastewater with increased soluble organics, along with optimisation of the hydraulic retention time (HRT), resulted in the highest VTR achieved by a pilot-scale MEC treating real wastewater. Peak HRT was 0.5-days, resulting in an average VTR of 3.82 kgCOD/m3∙day and a 55% COD removal efficiency. Finally, using the data obtained, a direct analysis of the potential savings from the reduced loading on AS was then made. Theoretical calculation of the required tank size, with the estimated costs and savings, indicates that the use of an MEC as a return sludge liquor pre-treatment technique could result in an industrially viable system.

Abstract Algae blooms are a seasonal problem in UK waters and during these periods interferences with treatment plants are reported. This paper presents an analysis of data from 2000 to 2005 demonstrating UK experiences of algae at water treatment works. Cell populations are lower than those reported in the 1970s and 1980s, but reach levels that adversely affect treatment processes. Diatoms and cyanobacteria dominate in spring and autumn respectively. A treatment works including pre‐oxidation, coagulation, flotation and filtration removes on average 96% of influent cells, while rapid gravity filters alone remove 63–75%. Cells present in the filtrate are typically either unicellular, micro‐algae, or flagellated algae. filter blockages in the spring and autumn are caused by large cells of complex morphology, including the diatoms Melosira and Asterionella. Overall, since the 1980s the key issue with respect to algae treatment has changed from one of treatability to that of process optimisation and economics.