Drinking Water Biofiltration Performance With Varying Ozone and Hydraulic Operations

Biological stability refers to the inability of drinking water to support microbial growth. This phenomenon was studied in a full-scale drinking water treatment and distribution system of the city of Zurich (Switzerland). The system treats lake water with successive ozonation and biological filtration steps and distributes the water without any disinfectant residuals. Chemical and microbiological parameters, notably dissolved organic carbon (DOC), assimilable organic carbon (AOC), heterotrophic plate counts (HPC) and flow-cytometric total cell concentration (TCC), were measured over an 18-month period. We observed a direct correlation between changes in the TCC, DOC and AOC concentrations during treatment; an increase in cell concentration was always associated with a decrease in organic carbon. This pattern was, however, not discerned with the conventional HPC method. The treated water contained on average a TCC of 8.97 × 10 4 cells ml −1 , a DOC concentration of 0.78 mg l −1 and an AOC concentration of 32 μg l −1 , and these parameters hardly changed in the distribution network, suggesting that the treated water had a high level of biological stability. This study highlights the descriptive value of alternative parameters such as flow-cytometric TCC for drinking water analysis, and pinpoints some of the key aspects regarding biological stability in drinking water without disinfectant residuals.

Hydrodynamics, Sediment Transport and Fluorescent Dissolved Organic Matter Modelling in a Shallow and Subtropical Reservoir

Impact of bromide on halogen incorporation into organic moieties in chlorinated drinking water treatment and distribution systems

,Wildfire events significantly contribute to the degradation of surface water quality by introducing ashes and unburnt carbon through runoff, resulting in elevated turbidity, increased levels of total suspended and dissolved solids, and higher concentrations of dissolved organic matter (DOM). Biofiltration has emerged as a sustainable and cost-effective water treatment technology, particularly valued for its environmentally friendly ability to remove DOM. This study evaluated the performance of process intensified biofiltration in removing dissolved organic carbon (DOC) from wildfire-impacted raw water using three bench-scale biofilters composed of different media: sand, granular activated carbon (GAC), and a combination of sand and GAC. The influent was pretreated using aeration and a roughing filter. DOC was tested at three levels: 20, 50, and 100 mg/L. Water quality parameters such as pH, turbidity, temperature, alkalinity, ultraviolet absorbance at 254 nm (UVA₅₂₄), specific ultraviolet absorbance at 254nm (SUVA₅₂₄) – calculated, and microbial activity – adenosine triphosphate (ATP), extracellular polymeric substances (EPS), and dissolved oxygen (DO) were monitored. Results indicate that at 20 mg/L DOC, the sand + GAC biofilter achieved the highest mean DOC removal efficiency of 70 ± 20%, followed by GAC (68 ± 16%) and sand (68 ± 22%). At 50 mg/L, removal efficiencies declined to 54 ± 16% (sand + GAC), 47 ± 19% (GAC), and 33 ± 19% (sand). At 100 mg/L, performance dropped remarkably, with average removals of only 16 ± 26% (sand + GAC), 16 ± 21% (GAC), and 12 ± 22% (sand). UVA₅₂₄ and SUVA₅₂₄ values remained below 2 L/mg·m, indicating the dominance of hydrophilic and low molecular weight organic matter. ATP concentrations peaked at 14 ± 2 mM in the sand biofilter, confirming its superior microbial activity. EPS analysis revealed higher sugar than protein concentrations, with tightly bound EPS peaking at 296 ± 37 mg/g total suspended solids. Elevated influent DOC concentrations were associated with increased pH (up to 9.52 ± 0.12), which may have negatively impacted microbial activity and DOC removal. Statistical analysis revealed a strong negative correlation between DOC concentration and DOC removal efficiency. Furthermore, analysis of variance confirmed that DOC concentration significantly influenced removal efficiency, while media type did not. However, Tukey post-hoc test showed that at DOC concentrations of 20 and 50 mg/L, the biofilters significantly reduced DOC levels, while at 100 mg/L, no significant reduction was observed, indicating diminished effectiveness at higher concentrations. The findings of this study underscore the robustness and adaptability of biofiltration systems in treating wildfire-impacted water, particularly in the effective removal of DOC and turbidity. By providing a nature-based, cost-effective treatment solution, biofiltration offers a sustainable and climate-resilient strategy for safeguarding drinking water sources against emerging contaminants.

Challenges to achieve biological stability in drinking water distribution systems Drinking water is distributed from the treatment facility to consumers through extended man-made piping systems. The World Health Organization drinking water guidelines (2006) stated that “Water entering the distribution system must be microbiologically safe and ideally should also be biologically stable”. The biological stability criterion refers to maintaining the microbial drinking water quality in time and distance from the point of drinking water production up to the point of consumption. However, uncontrolled growth of indigenous bacteria during water transport can result in the deterioration of aesthetic aspects of water, such as taste, colour, and odour, in exceeding of guideline values, and/or in technical problems. Controlling bacterial growth in piping systems and premise plumbings is very challenging (Chapter 2), and changes in drinking water microbial characteristics are often measured in networks distributing water with or without residual disinfectant such as chlorine, monochloramine or chlorine dioxide. In the Netherlands, drinking water is distributed without detectable residual disinfectant. Quantitative and qualitative knowledge on the indigenous bacterial communities and microbiological processes taking place during drinking water distribution is limited and in-depth investigations are required. New opportunities with novel analytical methods One reason for the lack of knowledge on bacterial growth controlling factors in drinking water distribution systems is that methods for characterizing drinking water bacterial communities are still relying heavily on culture-based techniques such as plate counts, developed more than 130 years ago. The conventional cultivation-based methods have major limitations: only a minute fraction (<0.1 %) of drinking water bacteria is detected, which is not representative of the drinking water bacterial community, and results are obtained only after a minimum of two days. During the last decade, new cultivation-independent techniques have emerged for the characterization of water bacterial communities. Among them, flow cytometry (FCM) enables the rapid detection and counting of all bacterial cells in water (within 15 minutes), and provides information on bacterial cell properties such as viability. Besides, high-throughput sequencing methods (e.g. 454-pyrosequencing or Illumina) enable characterization of the total bacterial community composition and structure at various taxonomic levels. FCM and high-throughput sequencing methods offer new perspectives for better and faster water microbiology monitoring and for increased understanding of the complex bacterial dynamics occurring during drinking water distribution up to the point of consumption (Chapter 2). Method development The primary goal of this study was to develop a methodological approach, based on advanced analytical methods, for the assessment of biological stability in drinking water distribution systems. A standardized, rapid and simple FCM method was shown to be highly reproducible and sensitive for total and intact bacterial cell enumeration. Changes in bacterial community characteristics could be detected based on bacterial cell concentrations and FCM fluorescence fingerprints, which are characteristic of each water sample (Chapter 3). Changes in fluorescence fingerprints were proven to be a rapid indication for changes in bacterial community composition, by comparing FCM and 16S rRNA gene pyrosequencing data obtained from the same drinking water samples. Combining the two methods enabled both quantitative and qualitative characterization of water bacterial communities (Chapter 4). An integrated approach was proposed for the assessment of bacterial growth-controlling factors in drinking water and for the evaluation of the impact of full-scale distribution conditions on bacterial growth extent. The approach combines (i) characterization of autochthonous bacterial communities in water samples collected at several locations in full-scale drinking water distribution systems, using FCM and high-throughput sequencing methods, (ii) comparison of changes in bacterial abundance recorded during water distribution and during controlled laboratory bacterial growth tests, and (iii) stepwise assessment of bacterial growth limitations in drinking water using straightforward bacterial growth potential tests (Chapter 5). Application of developed methodological approach to a full-scale drinking water system The developed methodological approach was applied to a Dutch full-scale drinking water treatment and distribution system operated without detectable disinfectant residual. Spatial and temporal variations were studied on short-term (hour, day, week) and long-term (seasonal) time-scales, and bacterial growth-limiting factors were investigated. Bacterial growth in the produced drinking water was limited both by organic carbon and inorganic nutrients (Chapter 5). Large seasonal variations in bacterial cell concentrations were recorded at the treatment effluent, which were congruent with water temperature fluctuations. Changes in bacterial community characteristics in the distribution system were minor compared to temporal variations in the treatment effluent (Chapter 6). However, all studies univocally showed that changes in bacterial community abundance, viability and/or community composition occurred during water distribution in the well-maintained network (Chapters 4, 5, 6 and 7). Changes were not detected with conventional bacterial detection methods. In-depth analysis of bacterial community composition in water samples, using pyrosequencing, showed that the core bacterial community did not change during water distribution, whereas high dynamicity was found in rare taxa (Chapter 7). Different bacterial cell concentrations were measured in the full-scale system and after incubation of the same water under controlled conditions, highlighting the effect of distribution conditions (e.g. temperature, pipe material, residence time) on drinking water microbial quality (Chapter 5). The results suggest that the extent of bacterial growth at one specifically studied location in the distribution system was not determined by the concentration of assimilable organic carbon in the treatment effluent. Likely not only one single parameter can be considered as controlling factor of microbial growth in drinking water distribution systems (Chapter 6). Recommendations From these observations, it is recommended to study microbial dynamics in drinking water distribution systems using a combination of controlled laboratory growth potential tests and in-situ characterization of the drinking water bacterial communities in the distribution network, which includes both spatial and temporal investigations. Applying such an approach to individual systems would provide better understanding of microbial dynamics during drinking water production and distribution, enabling (i) rapid and sensitive drinking water monitoring, (ii) effective corrective and maintenance actions and (iii) funded decisions for the optimization of water treatment production and/or distribution conditions to control bacterial growth in drinking water distribution systems. In this regard, the recent emergence of on-line flow cytometers will promote flow cytometry as an ideal monitoring method, for the rapid detection of system failure and targeted maintenance management.

Degradation of source water quality complicates water treatment processes, resulting in additional treatment cost and tap water quality deterioration. In this study, source water quality was investigated for 441 water supply systems (WSSs) during the period of 18years (1999-2016). The investigation was performed on 21 water quality parameters (WQPs) for groundwater (GWS) and surface water (SWS) sources. The averages of dissolved organic carbon (DOC), color, and Kjeldahl nitrogen (N) were much higher in SWS than GWS while other 18 WQPs (e.g., alkalinity, conductivity, and pH) were higher in GWS. In SWS, averages of DOC during 2000-2005, 2006-2010, and 2011-2015 were 6.08, 6.74, and 6.78mg/L, respectively. In these periods, pH were 6.39, 6.62, and 6.77, respectively. In GWS, averages of DOC in these periods were 1.43, 1.36, and 1.81mg/L, respectively, while pH were 7.50, 7.69, and 7.89, respectively. The DOC in SWS and GWS were increasing at the rates of 0.0722 and 0.0491mg/L/year, respectively, while pH were increasing at the rates of 0.0375 and 0.0441units/year, respectively. Trihalomethanes showed increasing trends in drinking water from SWS and GWS while haloacetic acids showed no trend. In SWS, DOC and its rate of increase were higher while in GWS, pH and its rate of increase were higher. The higher DOC and pH, and their increasing rates could increase disinfection byproducts (DBPs) in drinking water. Many DBPs are known as possible or probable human carcinogens and some DBPs are regulated. The other WQP and their increasing patterns can also impart new challenges, which are likely to increase the treatment cost and/or deteriorate drinking water quality.

Sustainable development goals (SDGs) 2 (zero hunger), 6 (clean water and sanitation), and 15 (life on land) are related to the human-water-soil nexus. Soil organic carbon and nutrients can be removed and transported to waterways through runoff and drainage. The main goals of this study are to quantify the water quality for irrigation and assess the dissolved organic carbon (DOC) contents in streams in the northern Nile Delta, Egypt. A 4-year water quality monitoring program is accomplished by collecting 35 irrigation and drainage water samples per year from the study area. The measured water quality parameters are as follows: salinity, pH, Na, SAR, Cl, and NO3–N. In addition, the DOC content is accessed. The salinity hazard ranged from moderate, for most irrigation samples, to high and very high for drainage samples. All collected water samples have low to medium sodium hazards. Results indicate that average DOC contents in irrigation canals are 2.32 and 2.93 mg L−1 for the summer and winter, respectively. The respective means of DOC concentration in drainage canals for the summer and winter seasons are around 3.96 and 5.09 mg L−1. This study revealed significant differences in EC, pH, Na, Cl, and SAR, as water quality parameters, between irrigation and drainage canals. Additionally, the studied agroecosystem has seasonal variability in DOC concentration in irrigation and drainage canals between summer and winter. Overall, reusing drainage water for irrigation in the study area requires the selection of suitable crops and site-specific management.

Size and XAD fractionations of trihalomethane precursors from soils

Dissolved organic matter (DOM) is a critical component in ecosystem processes and is the largest pool of organic carbon (C) in aquatic environments. In this study, we investigated the variability in quantity and quality of DOM in 3 large lakes in southern Ontario. Water quality parameters were coupled with excitation emission fluorescence spectroscopy and absorption spectra to characterize the DOM and investigate the overarching factors controlling DOM dynamics. The results show that Lake Simcoe has higher dissolved organic carbon (DOC) concentrations than lakes Erie, Ontario, and Hamilton Harbour (an embayment in western Lake Ontario) and suggest that a DOM source independent of watershed inputs is likely an important contributor to the DOC in this system. Five components were identified through parallel factor analysis (PARAFAC), representative of both terrestrial and microbial origin. Their relative intensities in the 4 Lake Simcoe end-members allowed the identification of dominant DOM sources in our studied ecosystems. Lake Simcoe seems to have a similar contribution of agriculturally derived DOM to lakes Erie, Ontario, and Hamilton Harbour. Lake Ontario, including Hamilton Harbour had on average a larger input of DOM derived from wastewater treatment plant effluents. The seasonal patterns in the different optical characteristics of DOM in Lake Simcoe compared to other systems suggested that DOM qualitative transformations, be it through photooxidation or microbial degradation, are likely very important processes in this lake. The role of DOM in Lake Simcoe may have important ecological implications for the cycling of C and the oxygen regime of this lake.

PDF HTML阅读 XML下载 导出引用 引用提醒 可溶性有机碳在米槠天然林不同土层中的迁移特征 DOI: 10.5846/stxb201310272590 作者: 作者单位: 福建师范大学地理科学学院,湿润亚热带山地生态国家重点实验室培育基地,湿润亚热带山地生态国家重点实验室培育基地,福建师范大学地理科学学院,湿润亚热带山地生态国家重点实验室培育基地,湿润亚热带山地生态国家重点实验室培育基地 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学青年基金项目(31100467); 福建师范大学优秀青年骨干教师培养基金(fjsdky2012008); 国家自然科学基金重点项目(31130013); 福建省自然科学青年基金项目(2011J05105); 高等学校博士学科点专项科研基金(优先发展领域)(20113503130001) Transport characteristics of dissolved organic carbon in different soil horizons in natural Castanopsis carlesii forest Author: Affiliation: State Key Laboratory of Humid Subtropical Mountain Ecology,State Key Laboratory of Humid Subtropical Mountain Ecology,State Key Laboratory of Humid Subtropical Mountain Ecology,State Key Laboratory of Humid Subtropical Mountain Ecology,State Key Laboratory of Humid Subtropical Mountain Ecology,State Key Laboratory of Humid Subtropical Mountain Ecology Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:选取我国中亚热带典型的常绿阔叶林米槠天然林(Castanopsis carlesii)为研究对象,采集林内米槠凋落物并通过挖剖面法分6个土层采集土样至1 m。通过浸提米槠凋落物得到可溶性有机碳(dissolved organic carbon,DOC)溶液并在室内模拟其在不同土层的淋溶过程,不仅分析了土壤性质对DOC淋溶的影响,还研究了淋溶前后DOC化学结构的变化,以阐明DOC在不同土层中的迁移特征及影响因素,探寻米槠天然林土壤的固碳潜力和DOC在土壤有机碳循环中的作用。结果表明:(1)下层土壤比上层土壤吸附DOC的能力更强,亲水性DOC与疏水性DOC间会争夺土壤颗粒表面的吸附位点,而且芳香化合物和大分子物质等疏水性DOC组分会被优先吸附;(2)红外光谱表明,芳香类和醚类等疏水性物质会优先被吸附,烷烃类物质却不易被吸附,土壤中原有的酚、醇类亲水性物质会被初始DOC中的疏水性物质置换出来;(3)土壤DOC的截留能力与粘粒、游离氧化铁含量呈极显著正相关,而与土壤有机碳和砂粒含量呈极显著负相关,其中土壤有机碳的含量是影响米槠天然林不同土层DOC截留量的关键因素。 Abstract:Dissolved organic carbon (DOC) is a mixture of organic compounds with varying molecular sizes and weights. In forest ecosystems, litterfall is a major aboveground resource of DOC, which supplies soils with carbon as a crucial component of terrestrial biogeochemical cycles. During the migration of litterfall-derived DOC from topsoils to subsoils, soils might retain, transform, or release DOC, depending on the chemical nature of DOC and its interactions with soil surfaces. These physicochemical processes contribute considerably to soil organic carbon (SOC) accumulation. It is generally accepted that soil properties have a great influence on the interaction between soil surface and DOC, with Fe/Al oxides constraining DOC losses and high SOC content being usually negatively correlated to DOC sorption. However, an inconsistency still remains regarding the extent to which soils properties impact DOC movement. In some cases topsoils rich in SOC might demonstrate higher DOC retention capacity. Although subsoils with abundant Fe/Al oxides are considered to have a stronger DOC retention capacity, relatively lower SOC content is often found in subsoils, and direct evidence for their higher carbon sequestration potential is rare. One reason for this maybe the amount of DOC from aboveground litterfall, which is not sufficient and little DOC can reach subsoils. Another reason might be that highly sorptive DOC is preferentially absorbed by topsoils, and DOC that reaches subsoils has a weak affinity for soil surfaces. Supplying individual soil horizons with a common DOC solution is thus a good way to differentiate their carbon sequestration capacities. Natural Castanopsis carlesii forests are dominant evergreen broad-leaf forests in mid-subtropical China, and interaction between litterfall derived DOC and red soil (Ferralic Cambisols, World Reference Base) is now recognized as one of the most important mechanisms of C sequestration in this region. To solve inconsistencies about factors controlling DOC translocation in soils and to provide direct information to differentiate carbon sequestration potential between soil horizons, a 200-year-old natural Castanopsis carlesii forest without human interference was selected for undecomposed litter collection and soil sampling at the depth of 0-10 cm, 10-20 cm, 20-40 cm, 40-60 cm, 60-80 cm, 80-100 cm from each of the three profiles in the site. After extracting DOC from the collected litter with ultrapure water, we supplied individual soil cores with the common DOC in the laboratory. We not only analyzed the influences of soil properties on DOC interception, but also studied the changes in structural composition of DOC before and after leaching. The results showed that: (1) DOC interception in subsoils was greater than that in topsoils. Hydrophilic and hydrophobic DOC competed for binding sites on soil surfaces, and aromatic compounds and macromolecular substances of hydrophobic components were preferentially adsorbed by soils; (2) infrared spectrum suggested that hydrophobic materials such as aromatic substances and ethers were much more ready to be adsorbed than alkane materials, while indigenous hydrophilic substances such as phenols, alcohols could be displaced by hydrophobic components of DOC; (3) there was significant positive correlation between DOC interception and the content of clay and free iron oxide and significant negative correlation between DOC interception and the content of sand and soil organic carbon. Soil organic carbon content was the key factor affecting DOC interception in different soil horizons in natural Castanopsis carlesii forest. 参考文献 相似文献 引证文献

Peatlands are important due to their high carbon storage, their role in suppressing climate change processes, and their importance for local and global communities’ livelihood. Large amounts of organic carbon pools in peatlands can be released into the environment as gaseous emitted carbon and lost through waterways (fluvial). The carbon released through the water stream consists of organic and inorganic forms and is partly in the form of CO2 and CH4 gases. The organic form consists of dissolved organic carbon (DOC) and particulate organic carbon, where DOC is the most dominant organic carbon in water sourced from peatlands. This research's objectives were to study the DOC concentration of peat water resulting from the hydrological condition's difference and the peat thickness overlaying the sulfidic substratum. The study was carried out in the Pangkoh area of Pulang Pisau district of Central Kalimantan. Peat water is taken on PVC pipes installed on each plot representing different peat thicknesses (deep, moderate, and shallow peat) at a depth of 25, 50, 100, 150, 200, and 250 cm from the soil surface. The water sampling was conducted on the peak wet season, during the transition from wet season to dry season and during the peak dry season. The results showed that DOC was influenced by peat thickness, depth of sulfidic material, and groundwater level. The release of DOC is higher from the deep peat than from the thin and moderate peat. The difference in DOC concentration between peat thickness is also related to the electrical conductivity of the peat water. The results showed a negative correlation between electrical conductivity and DOC concentration. The negative correlation was significant in the observation of the rainy and dry seasons, while in the transitional season, it was not significant.

مصرف بی‌رویه و نادرست آفت‌کش‌ها سبب آلودگی محیط زیست شده است. به منظور کاهش تحرک این ترکیبات در خاک و آلودگی محیط زیست، لزوم کمی نمودن سرنوشت علف‌کش‌هایی با مصرف خاکی وجود دارد. در این تحقیق جذب ماده آلی محلول با غلظت‌های 0، 10، 20، 40، 80 و 160 میلی‌گرم کربن آلی در لیتر در دو خاک در شرایط آزمایشگاهی و در دمای ثابت مورد بررسی قرار گرفت. همچنین تأثیر pH و ماده آلی محلول با غلظت‌های مختلف (0، 10، 40 و 160 میلی‌گرم در لیتر) بر جذب علف‌کش متری‌بیوزین (با مقادیر 5/1، 2، 3، 4، 5 و 6 میلی‌گرم در کیلوگرم) مورد مطالعه قرار گرفت. نتایج نشان داد که ماده آلی محلول بر روی خاک‌ها جذب سطحی شده و هم‌دماهای آن‌ها با مدل فروندلیچ مطابقت داشت. جذب سطحی علف‌کش متری‌بیوزین در هر دو خاک 1 و 2 در حضور ماده آلی محلول کاهش نشان داد. به‌طوری که بیشترین مقدار جذب متری‌بیوزین در هر دو خاک 1 و 2 در تیمار بدون حضور ماده آلی محلول به ترتیب 19/38 و 71/29 میلی‌گرم در کیلوگرم و کمترین میزان در تیمار 160 میلی‌گرم ماده آلی محلول در لیتر به ترتیب 75/7 و 42/5 میلی‌گرم در کیلوگرم بدست آمد. جذب متری‌بیوزین در دامنه pH 5/5-4 در خاک 1 و 2، در تیمار عدم حضور ماده آلی محلول به ترتیب 54/8 و 23/6 درصد بیشتر از تیمار حضور ماده آلی محلول محاسبه گردید. به‌طور کلی افزایش غلظت ماده آلی محلول، سبب کاهش جذب متری‌بیورزین بر روی دو خاک گردید.

Compositions and concentrations of dissolved organic matter, selected elements and anions in German drinking waters.

Two billion people lack access to safely managed drinking water services, many of these are in low/middle income countries where centralised systems are impractical. Decentralised point-of-use drinking water treatment systems offer alternative solutions in remote or resource constrained settings. The main aim of this study was to assess the long-term (3 year) operation and performance of a point-of-use drinking water treatment system (POU-DWTS). A biologically contaminated urban drainage pond was used as a water source and the quality of the produced drinking water was assessed over two independent trials. The decentralised POU-DWTS combined ultrafiltration membranes with disinfection from electrochemically generated hypochlorous acid (HOCl). The operational parameters, such as flow rate, free available chlorine and transmembrane pressure, were monitored in real-time and recorded via a remote monitoring system. Water quality from the source and treated water was assessed over two trial periods within the 3-year operational trial: an 11-week period at the start and a 22-week trial at the end. All water samples were assessed for a range of basic, chemical, microbiological and metal water quality parameters. The results demonstrate that the decentralised POU-DWTS is capable of continuously producing high quality drinking water when HOCl is continuously used to dose water prior to entering the ultrafiltration [UF] membranes. Over the 3-year operational study, the continuous dosing of HOCl pre-UF membranes resulted in stable permeability, indicating no occurrences of irreversible biofouling within the UF membranes and that good membrane ‘health’ was maintained throughout. As such, there was no need to replace the UF membranes nor undertake acid/alkaline chemical cleans at any point throughput the three-year study. The POU-DWTS continuously produced high quality drinking water, resulting in 6453 m3 of drinking water produced over the trial period, that met international water quality standards, at a community scale within the location studied.

Potable water treatment in the state of Western Australia is challenged in many instances by the presence of high and variable levels of dissolved organic carbon (DOC), particularly in surface water supplies. In recent years the effects of climate change on local sources, in combination with the ever-present requirement for on-going disinfection effectiveness and disinfection by-product regulation has driven the need for the development of innovative, sustainable processes for the removal of DOC. Extensive pilot plant studies over a number of years have demonstrated the effectiveness of biological filtration for cost-effectively managing a variety of high DOC source waters, consequently biofiltration is seen as a process of choice for organics removal in drinking water in Western Australia. Although there are a number of indicators for measuring the efficacy of organic carbon reduction across biological treatment processes (e.g., DOC concentration, SUVA, etc), none currently are able to reliably inform on the change in the “non-refractory” organic carbon component of DOC (i.e. biodegradable dissolved organic carbon [BDOC]) which arises from microbiological metabolic activity in the biological treatment process. Knowledge of this parameter is of critical importance to the understanding of biological stability of the finished water entering a distribution system. We have therefore investigated a number of analytical procedures in order to develop a robust test method to accurately quantify this important aspect of biofilter performance. The paper reports a comparison between conventional and rapid methods for the determination of BDOC using immobilised biofilms enriched on deep aquifer water. Effective sample collection, preparation and method of analytical analysis, method validation using natural source water with and without addition of standard amounts of assimilable organic carbon (e.g. acetate), and reproducibility of test results are discussed.