Water Quality Improvement Measures Research Articles

Research on the Adjustment Strategy and Effect Evaluation of Oilfield in the Late Stage of Water Drive with Ultra High Water Cut

This article delves into the adjustment strategies for high water cut oil fields in the later stage of water flooding and their impact on oilfield performance. We conducted a series of experiments, including optimizing the layout of injection wells, comparing water quality improvement measures, comparing oilfield management and operation strategies, and applying efficient oil recovery technologies, to analyze and evaluate the effects of different strategies in detail. The experimental results indicate that the production and recovery rate of the oilfield show a stable increase over time, starting from an initial value of approximately 95 units. At the end of the 10th time cycle, this indicator accumulated to around 950 units. This indicates that artificial lifting technology has shown stable performance in improving oilfield performance. The results of this study emphasize the importance of adjusting strategies. By optimizing the layout of water injection wells, improving water quality, optimizing management and operation, and applying efficient oil recovery technologies, it is possible to significantly increase the production and recovery rate of oil fields in the later stage of water flooding with ultra-high water content, reduce the expansion of water shear zones, and achieve better economic benefits and sustainable development. These results are of great significance for practical applications in the field of petroleum engineering.

Analysis of future nitrogen and phosphorus loading in watershed and the risk of lake blooms under the influence of complex factors: Implications for management

For the management of eutrophic lakes, watershed nitrogen and phosphorus control is oriented to future water quality. Assessing future nutrient dynamics and the risk of lake eutrophication is necessary. However, current assessments often lack integrated consideration of socioeconomic and climatic factors, which reduces the reference value of the results. In this study, a typical large shallow lake Chaohu, which is highly influenced by human activities, was selected as the study area, and the current and future total nitrogen (TN) and total phosphorus (TP) loading in the basin were analysed using the improved MARINA model, and the risk of water bloom were assessed. The results showed that socioeconomic factors alone varied future TN and TP loading by −24% to 32% and −40% to 34%, respectively, under different development patterns. After considering the effect of increased precipitation, the changes of TN and TP loading became −10% to 163% and −29% to 108%, respectively. The effect on loading reduction under the sustainable development pattern was weakened (58% and 28% for TN and TP loading, respectively) and the increase in loading under the brutal development pattern was significantly amplified (409% and 215% for TN and TP loading, respectively). The adoption of active environmental policies remained an effective way of loading control. However, the risk of water bloom in local lake areas might persist due to factors such as urbanization. Timely and comprehensive assessments can provide managers with more information to identify key factors that contribute to the risk of water blooms and to develop diverse water quality improvement measures. The insights from our study are applicable to other watersheds around the world with similar socio-economic background and climatic conditions.

Historical Trends and Driving Forces of River Water Quality Improvement in the Megacity Shenzhen, China

The water quality of urban rivers in China has undergone significant improvement since the 13th Five-Year Plan period (2016–2020). Among these, urban rivers in Shenzhen are the most representative. Assessing historical trends and analyzing the driving forces of river water quality improvement is of great importance and provides valuable insights. This study selects two typical watersheds, Maozhou River and Longgang River, to explore how water quality trends link with water control projects in Shenzhen from 2003 to 2020. The historical trends were evaluated using a recently developed index called WQI-DET, which considers DO, COD, NH3-N, TP, and anionic surfactants. Results showed that both rivers were seriously polluted before 2010 and gradually improved during the 12th Five-Year Plan period. After 2010, the water quality improved rapidly thanks to the environmental remediation of the mainstream, especially the interception project of Longgang River around 2010, and the Maozhou River interception project in 2015. The rainwater and sewage diversion renovation project mainly contributed to meeting the standards for Class IV water bodies during the 13th Five-Year Plan period. This study reveals the semi-quantitative link between comprehensive water quality improvement and pollution control engineering measures. It is a helpful review for Shenzhen and provides a useful reference for other cities.

Microbiome response in an urban river system is dominated by seasonality over wastewater treatment upgrades

BackgroundMicroorganisms such as coliform-forming bacteria are commonly used to assess freshwater quality for drinking and recreational use. However, such organisms do not exist in isolation; they exist within the context of dynamic, interactive microbial communities which vary through space and time. Elucidating spatiotemporal microbial dynamics is imperative for discriminating robust community changes from ephemeral ecological trends, and for improving our overall understanding of the relationship between microbial communities and ecosystem health. We conducted a seven-year (2013–2019) microbial time-series investigation in the Chicago Area Waterways (CAWS): an urban river system which, in 2016, experienced substantial upgrades to disinfection processes at two wastewater reclamation plants (WRPs) that discharge into the CAWS and improved stormwater capture, to improve river water quality and reduce flooding. Using culture-independent and culture-dependent approaches, we compared CAWS microbial ecology before and after the intervention.ResultsExaminations of time-resolved beta distances between WRP-adjacent sites showed that community similarity measures were often consistent with the spatial orientation of site locations to one another and to the WRP outfalls. Fecal coliform results suggested that upgrades reduced coliform-associated bacteria in the effluent and the downstream river community. However, examinations of whole community changes through time suggest that the upgrades did little to affect overall riverine community dynamics, which instead were overwhelmingly driven by yearly patterns consistent with seasonality.ConclusionsThis study presents a systematic effort to combine 16S rRNA gene amplicon sequencing with traditional culture-based methods to evaluate the influence of treatment innovations and systems upgrades on the microbiome of the Chicago Area Waterway System, representing the longest and most comprehensive characterization of the microbiome of an urban waterway yet attempted. We found that the systems upgrades were successful in improving specific water quality measures immediately downstream of wastewater outflows. Additionally, we found that the implementation of the water quality improvement measures to the river system did not disrupt the overall dynamics of the downstream microbial community, which remained heavily influenced by seasonal trends. Such results emphasize the dynamic nature of microbiomes in open environmental systems such as the CAWS, but also suggest that the seasonal oscillations remain consistent even when perturbed.

Investigating the effects of inflow river water quality on lake nutrient-concentration variations: a case study in Gehu Lake, China

Context Controlling the inputs of nutrients, one of the main sources of lake pollution from inflow rivers, is an important way to protect lakes. Aims To obtain a whole picture of spatiotemporal variation of water quality in Gehu lake and its main inflow rivers from 2011 to 2018, and to study relationship of water quality between lake and inflow rivers. Methods We analysed the relationship by using correlation analysis and BATHTUB model and discussed the goal of collaborative control by setting up different scenarios. Key results The concentrations of total nitrogen (ρ(TN)) and total phosphorus (ρ(TP)) are the main water pollutants in Gehu Lake and it continues to maintain the middle-eutropher state. ρ(TN) and ρ(TP) in the lake have a significant negative correlation with the quantity of water inflow and a significant positive correlation with ρ(TN) and ρ(TP) in inflow rivers. Conclusions It showed that when ρ(TN) and ρ(TP) in inflow rivers decreased by 25%, ρ(TN) and ρ(TP) in Gehu Lake decreased by 21.01 and 22.64%. Furthermore, when ρ(TN) and ρ(TP) in inflow rivers decreased by 50%, they correspondingly decreased by 40 and 36.91% in the lake. Implications Our findings provide effective control of water quality in Gehu Lake and give a guide for environmental governance and water-quality improvement measures.

Instream filtering system for the removal of suspended solids in King Yip Street Nullah, Kwun Tong

The preliminary design of the project “Revitalization of Tsui Ping River” recommended a few water quality improvement measures aiming to enhance the aesthetic appearance and environmental conditions of the existing King Yip Street Nullah in Kwun Tong, including the use of a cost-effective instream filtering system to remove suspended solids (SS) in dry weather flows. However, the effectiveness as well as operational and maintenance experience of instream filtering systems in Hong Kong is not well established. Thus, we conducted a site trial to ascertain its effectiveness before full-scale implementation. The results showed that the sand trap screened a lot of sandy materials during the site trial period, especially during rainfall events. The instream filtering system with a gravel size of 80−120 mm effectively removed SS and total organic carbon from the water. We recommend that for the instream filtering system to be implemented in other nullahs in Hong Kong, larger dimensions (length of 4−9 m) with possible flow control (0.3−1.5 m3/h) measures could be considered when the site conditions (water depth of 1.1−1.5 m and water turbidity level below 500 NTU) allow. Overall, this study provided indispensable guidance to formulate the future design of filter sizing criteria based on targeted rainfall events and specific hydrological objectives.

Second derivative UV\u2013visible spectroscopy characterizing structural components of dissolved and particulate organic matter in an urbanized river

BackgroundSpatio-temporal variations of structural components of the POM–DOM fractions exhibit in urban rivers, which is valuable information to reveal dynamic migration and transformation within and between the organic matter pools, also provide important support for river water quality improvement and management measures. Second derivative UV–visible spectroscopy (SDUVS) was applied to simultaneously characterize structural components and spatial variations of dissolved (DOM: Diameter < 0.2 μm) and particulate (POM1: 0.2 < diameter < 0.7 μm; POM2: diameter > 0.7 μm) organic matters in an urbanized river of northeast China.ResultsThirty-six water samples were collected from mainstream and tributaries along a human impact gradient, i.e., rural, town and urban regions. The DOM was a representative fraction for the natural organic matter pool, which was mostly derived from allochthonous and terrestrial sources. Four components C1 to C4 were identified from the POM–DOM fractions by the SDUVS. The C1 associated with phenolic groups and the C2 related to carboxylic groups were dominant for the organic matter pool. The C3 was composed of the primary humificated materials, and the %C3 was kept relatively consistent in the organic matter pool. The C4 presented deeply humificated organic matter with the increase of aromatic and alkyl structures. The average %C4 of the POM pool was higher than that of the DOM pool, indicating that the humification degree of the POM fractions was higher than that of the DOM fraction.ConclusionsMoreover, the tributaries had a higher average %C4 within the DOM than the mainstream, and trends of the POM pool were similar to the DOM pool. The trophic level of the river water decreased in the order of urban region > town region > rural region, while the molecular sizes of the POM–DOM decreased in the order of rural region > town region > urban region.Graphical

Water quality improvement measures at the Yagang cross-section in the Pearl River Delta based on the calculation of excessive pollutant fluxes

Abstract The aim of this study was to quantify the sources of pollution in the Yagang River Basin. A 1-D hydrodynamic model and a 1-D water quality model were combined with the excessive pollutant flux analysis method to calculate pollution data of the Yagang area. The results showed that upstream pollution was the primary cause of water quality degradation for the Yagang Basin, exceeding the water quality standards. In addition, the pollution problem ranking of the entire basin was as follows: the Yagang area (30.4%) &amp;gt; the Foshan area (23.2%) &amp;gt; the Baini River Basin (13.1%) &amp;gt; the Liuxi River Basin (0.6%). In addition, the rainy season had the greatest influence on pollution concentrations. It was also concluded that if the boundary water quality could meet the inspection requirements (class IV water), and the internal research area sewage collection rate reached 60%, the ammonia-nitrogen (NH3-N) in the river discharge would reach 35.7%. This would allow the water quality at the Yagang cross-section to reach standard class IV.

Are the Water Quality Improvement Measures of China's South-to-North Water Diversion Project Effective? A Case Study of Xuzhou Section in the East Route.

Xuzhou is the hub city of the east route of China’s South-to-North Water Diversion (SNWD) project and implemented dozens of measures to ensure the water quality security of the water transmission line. In order to detect the effectiveness of water quality improvement measures, the monthly water quality data of five water quality parameters from 2005 to 2015 of six state-controlled monitoring sites in Xuzhou section were selected for analysis. The results showed that the water quality improved from 2.95 in 2005 to 2.74 in 2015, as assessed by the comprehensive water quality identification index (CWQII), and basically reached the Class III standards of China’s Environmental Quality Standard for Surface Water (GB3838-2002) from 2011 to 2015. The trend analysis showed that the decline of ammonia nitrogen (NH3-N) was the most obvious among the five water quality parameters. However, the concentrations of phosphorus (TP) showed significant upward trends at three sites. The positive abrupt change of time series of water quality occurred in 2009–2011. The identification of influencing factors of water quality changes by multivariate statistical methods found that the urbanization factor accompanied by a decrease in agricultural nonpoint source pollution emissions and the enhancement of wastewater treatment capacity, the closure of factories with substandard emissions and precipitation were the major influencing factors of most water quality parameters, which confirmed the effectiveness of measures for water quality improvement in Xuzhou.

The water exchange and water quality improvement measures on the example of the Gulf of Cheboksary

This paper is dedicated to the Gulf of Cheboksary. The gulf has an important recreational and decorative function. It has been an integral part of the urban landscape for several decades. There is an eutrophication process, accompanied by the development of blue-green algae and the appearance of an odour in early spring, despite the water quality improvement measures. Measures that will improve the water exchange in the Gulf are proposed in this paper. Problems with the sanitary condition of the water body can occur without taking these measures. Therefore, the theme of this research is quite urgent.

QUAL2E 모형을 이용한 오염원변화에 따른 충주댐 상류 유역의 수질 개선 효과 분석

본 연구는 충주댐 상류유역의 수질개선대책을 수립하기 위해 실시된 상위 및 관련계획, 수리 수문환경, 환경기초시설 현황 및 계획, 수질현황, 주요 오염원 발생 및 배출현황 등의 자료조사를 통하여 수질오염원을 파악하고 국내에 알려져 있는 수질모델 중 신뢰도가 인정되어 하천수질모의에 널리 적용되고 있는 QUAL2E 모형을 적용하였다. 연구 결과를 토대로 하여 충주댐 상류 유역의 수질개선을 위한 규제와 정책 방안들을 고려한 수질예측이 필요할 것으로 판단되며, 특히 충주댐 상류 유역의 오염원별 수질을 관리하는 방안과 더불어 오염원별 배출부하량이 높은 지역의 대형 환경기초시설에 의한 고도처리시설 도입 및 비점오염 저감시설에 의한 부분을 고려한 추가적인 연구가 필요할 것으로 판단된다. The research grasps water quality contamination source by investigating the data that are superordinate laws and the related plans implemented for establishing water quality improvement measures of upper stream for Chung-Ju Dam, present conditions of the hydraulic and hydrology, the present conditions and plans of environment basic facilities, and present conditions of main contamination source's occurrence load and discharge load, etc. The research used the QUAL2E simulation which is being widely applied to simulation of river water quality because the QUAL2E has high credibility among water quality simulations known throughout the country. On basis of this research, regulations and politic alternatives are required in order to water quality improvement upper stream for the Chung-ju dam, especially establishing processing facilities in the region where loading amount is concentrated should be considered with the additional research regarding cost-efficient facility of pollution source.

Trend Analysis of Water Pollutant at Summer Rainfall Season

This study, with Hongdong Reservoir, is intended to evaluate the changes in water quality in the lake before and after rainfall in summer. Various non-point source pollutions are scattered around the reservoir, and to determine the pollution level by pollution source, samples were taken at the same point before rainfall (1st), during rainfall (2nd) and after rainfall (3rd) and concentration was measured. Pollutant concentration curve at the measuring points (HDS1, HDS2, HDS3) appeared to be similar with the hydrological curve. When comparing the concentration immediately before rainfall with event mean concentration (EMC), SS and COD were 4 - 59 times and 1 - 4 times, respectively. However, when it comes to total nitrogen (T-N), concentration arrived at the reservoir stayed the range of 1.3 - 12.0 mg/L in all 3 cases without significant variation, which indicated that total nitrogen load is critical when arriving at the reservoir, irrespective of rainfall, and thus it’s necessary to consider non-point source pollution runoff also in addition to point source pollution when developing the water quality improvement measures in reservoir.

마산만 재해방지시설을 이용한 해수교환 방안에 관한 연구

마산만은 반폐쇄성 해역으로, 느린 유속과 육상오염물질의 하천부하 등으로 인해 심각한 수질문제를 가지고 있으며, 동시에 폭풍해일에 취약한 입지적 특성을 나타내고 있다. 이 중 폭풍해일 저감대책으로 제시된 재해방지시설을 운용함과 동시에 이를 마산만 내측 수질개선에 활용하는 방안을 모색하였다. 즉, 재해방지시설을 가동하여 마산만 내측과 외측의 수위조건이 다를 때 발생하는 수두차를 이용하여 만 내 외의 해수를 교환하였다. 재해방지시설의 위치를 기존 만 입구부, 마창대교 인근, 그리고 돝섬 인근으로 가정하였으며, 선박운항 횟수와 연간조위를 분석하여 통항빈도가 가장 낮은 새벽시간(01~05) 및 수두차가 가장 큰 대조기에 운용된다고 가정하였다. 또한, 재해방지시설과 함께 약 10km 길이의 유출 입 관로를 통한 내 외해수의 해수교환 촉진을 위한 추가 실험안을 구성하였다. 수치모의 결과, 현재상태의 경우 마산만 전체 해수교환율은 38.62%을 나타냈으며, 모든 실험안에서 마산만 내 모든 구역에서 꾸준한 증가 추세를 보이고 있다. 이에 반해, 마산만 입구부와 비교한 마산만 내측의 해수교환율은 매우 낮게 나타나 반폐쇄성 내만해역의 특성을 잘 재현하는 것으로 판단된다. 재해방지시설과 관로를 이용한 실험안을 분석한 결과, 현재상태와 비교하여 재해방지시설을 운용한 경우 해수교환율이 높고, 그 운용빈도가 많아질수록 더 많은 순환이 이루어지는 것으로 나타났다. 또한, 재해방지시설에 의해 발생된 수두차를 이용하여 관로를 통해 해수를 유입 혹은 유출한 경우 마산만 가장 내측의 수질이 개선되는 것으로 나타났다. 재해방지시설의 위치는 마창대교 남측과 비교하여 마산만 입구와 돝섬에 위치한 경우 해수교환 효과가 더 좋게 나타났다. 한편 마산만 전체영역에 대한 해수교환율은 만 입구에 재해방지시설이 위치한 경우가 돝섬에 위치한 경우보다 높지만, 마산만 내측을 포함한 해수교환율은 반대로 돝섬에 위치한 경우가 더 높게 나타났다. Masan bay with a semi-enclosed waters has serious water quality problems due to the low flow and river pollution load from land, and shows the vulnerable locational characteristics to storm surge. We are seeking the way of both operating disaster prevention facilities and water quality improvement measures in the bay. That is, the water was exchanged using the head difference occurred by operating disaster prevention facilities. The location of disaster prevention facilities was assumed to be in the inlet of the bay, in the vicinity of Machang bridge, and in the vicinity of Dot island and the operation time was assumed to be early morning hours(01~05) considering the number of shipping passage and annual tide, and spring tide of the largest head difference. In addition, the experiment case of water exchange including the in-outflow feeder pipe was tested. According to the simulation results, water exchange rate in all experiments has shown a steady increase. Water exchange rate of the whole of Masan bay in the case of present is 38.62%. The water exchange rate of the inside of Masan bay compared with the inlet of bay, appeared to be very low. Thus, we judged that the characteristics of semi-enclosed waters were well reproduced. On the results of the experiment of disaster prevention facilities and in-outflow feeder pipe, the case of the operation of disaster prevention facilities, water exchage rate is high compared with the case of present. And, the higer the operating frequency, the more water exchange is appeared. The cases of water exchange prevention facilities through the in-outflow feeder pipe caused by the head difference, also showed the higest improvement of the water quality. Compared with the south of Machang bridge, the effect of water exchange was better in the inlet of Masan bay and Dot island. On the other hand, the inlet of Masan bay is higer than Dot island as for water exchange of the whole of Masan bay, but opposite, water change rate including Masan inside was higher in the case of Dot island.

Predicting the occurrence of stoneflies (Plecoptera) on the basis of water characteristics, river morphology and land use

Stoneflies are macro-invertebrates that are sensitive water quality indicators. Here, their occurrence was modelled based on physical–chemical water characteristics, river morphology and land use with five different modelling techniques. In a case-study in Flanders, stoneflies were found in 219 samples and two sets of absence data were gathered: 219 random samples from sites without stoneflies and 219 samples from sites downstream of each sampling site where stoneflies were observed. With both random and downstream absences, logistic regressions, artificial neural networks, support vector machines, random forests and classification trees could all successfully predict stonefly occurrence. For most environmental parameters, significant differences were found between sites with and without stoneflies. As stoneflies were only detected in a few percent of the samples, the ecological water quality is obviously still too low in most watercourses. Based on planned water quality improvement measures, an ensemble forecast using the five mentioned modelling techniques predicted that stonefly prevalence will only increase marginally by 2015 and 2027. To meet the European Union Water Framework Directive requirements, which states that all surface waters should obtain a good ecological quality, a more ambitious management plan is needed to decrease nutrient concentrations and improve habitat quality.

서낙동강 수문 운영에 따른 동적 수질 변화 연구

호소형 하천으로 정체수역 특성을 갖는 서낙동강에서의 대저수문 유입량과 녹산수문 방류량은 오염총량관리 시행계획 대상유역인 낙본N 단위유역의 수질관리에 있어서 매우 중요한 영향을 미친다. 하지만 기준유량을 산정하기 위한 실측자료는 매우 부족하고, 대저수문과 녹산수문의 운영자료는 수문개도시 최대가능방류량만을 사용하고 있으므로 실측 방류량과는 많은 차이를 보이고 있다. 본 연구에서는 대저수문과 녹산수문의 운영자료를 수집하고, 이를 환경부 수질측정망 월별 수질변화와의 비교를 통해 분석하였다. 또한 대저수문과 녹산수문의 운영에 따른 서낙동강 본류의 비정상상태의 유량변화와 이에 따른 수질변화를 실측하였다. 낙동강 본류 수위, 서낙동강 수위, 조위 등의 영향을 받는 대저수문 유입과 녹산수문 방류에 의한 서낙동강 유량변화를 실측하였으며, 이는 대저수문과 녹산수문의 최적 운영을 통한 서낙동강의 수질 개선 대책 수립의 기초자료로 활용될 수 있을 것으로 판단된다. The inflow from Daejeo gate and the outflow from Noksan gate in Seonakdong river, which is a reservoir-like river with the characteristics of stagnant water, is very important for TMDLs (Total Maximum Daily Load) of Nakbon N unit watershed. However, there are very few measured data for calculating base flow. The operating data is much different from the actual measured data because the probable maximum flowrate is used for gate operation. In this study, the operating flowrate data of Daejeo and Noksan gates are compared with the monthly water quality data from Ministry of Environment monitoring station. The dynamic change of the flowrate and the water quality is also measured for the operation of Daejeo and Noksan gates. The flowrate of Seonakdong river is measured, which is affected by the gate operation, the water elevation difference of Nakdong river and Seonakdong river, and the tidal elevation. The results of this study can be used for establishing the water quality improvement measures by the optimal gate operation.

Regional Environmental Governance and Social Capital: A Case Study of Mangyeong River Communities

With a growing concern over the quality of water running downward into the Saemangeum area, the public-private-academic partnership for water quality management called Jeollabuk-do River Restoration was inaugurated in 2011 at the municipal level. On account of the fact that the water quality control as common pool resource faces a social dilemma, non-point source pollution requires cooperation particularly among river community residents supported by the public-private-academic partnership. Drawing upon a survey of the residents of Wanju-gun, Iksan-si, and Gimje-si along the Mangyeong River, we find that, firstly, residents including farmers do not consider diffuse pollution from the agricultural riverbank to be serious. Secondly, the partnership's activities are not sufficiently familiar to residents. Thirdly, residents commonly tend to perceive the current form of regional environmental governance as a managerial model that is led by the local government. Fourthly, residents of Iksan-si and Gimje-si have significantly higher levels of social capital. Lastly, norms of cooperation can be explained by civic associations and regional identity, with more cooperation from Iksansi residents. Several implications of these findings are discussed.Keywords: Quality Control, Non-point Source Pollution, Social Dilemma, Regional Environmental Governance, Social Capital, Cooperative NormsIntroductionSince the biggest land reclamation project in the history of South Korea called Saemangeum Seawall was launched in 1989 as a national project for farmland construction, water demand estimation was the main subject of research during the 1990s. The issue of water quality was first raised in 1996, and thereafter, the central government of South Korea implemented various tasks informed by the Water Quality Improvement Measures Phase 1 (2001-2010). Meanwhile, the government changed the fundamental design of the Saemangeum Seawall project in October 2008 to increase the share of land for non-agricultural purposes such as industry, tourism and leisure, international affairs, science, and research, with the proportion of agricultural land down to 30%. To this end, the government upwardly adjusted the overall level of water quality to grade 4 for the agricultural sector and grade 3 for the urban sector, according to the Comprehensive Development Plan passed in March 2011 by the 6th Saemangeum Committee. Highlighting the priority of the intensive maintenance of two rivers named Mangyeong and Dongjin in the upstream regions of the Saemangeum land, Water Quality Improvement Measures Phase 2 (2011-2020) focuses mainly on how to effectively control pollution from livestock farms, point source pollution, and non-point source pollution. Pertinently, the government began to draw new attention to various diffuse sources of water pollution (e.g., by means of combined sewer overflow facilities and low impact development-based urban planning) in contrast to the earlier approach to water quality management which is disproportionately concerned about livestock wastes and point sources of pollution.The pro-growth regime in leollabuk-do, having consistently alleged that the future of leollabuk-do depends solely on the success of the Saemangeum project, took active steps in response to the idea that a regional agency is required for more collaborative governance of water quality improvement at the provincial level immediately after the central government announced the Water Improvement Measures Phase 2. The leollabuk-do governor took the initiative in arranging the leollabuk-do River Restoration Association in March 2011, which is an enlarged version of the Public-Private-Academic Partnership for Eco-Friendly Mangyeong River (2002-2011). This new association presumes itself as the first case of a municipal-level public-private-academic partnership regarding river restoration since the launch of Koreas local self-governing system. …

Benefit-Cost of River Water Environment and Investments Related to Water Environment in the River Basin

Huge investments for water and waste water management and ambient water environment improvement have been conducted for many years in economically developed countries including Japan. The investment for water supply, on-site and centralized municipal waste water treatment systems (WWTSs), river water purification facilities and dissemination of soft measures in households, and benefits from water quality improvement in the Yamato-gawa River Basin, Japan, in 1965–2009 were summarized based on the statistical data and existing literature. The benefits include ambient water quality improvement and employment of local fishery persons. The former was estimated based on the existing literatures. Average and 75% biological oxygen demand (BOD) in the River was less than 5 mg l-1 in 1963, rapidly deteriorated in the 1960s and exceeded 20 mg l-1 in 1970. The national level regulations on ambient water quality and pollutant discharges have been established in 1970. The relationship between accumulated investments and 'difference of estimated BOD based on BOD generation (PG(BOD)) and monitored BOD' (ΔBOD) suggested the critical history of pollutant discharge, water quality, and investments on the measures to improve river water quality: effects of investments were negative and not yet observed in the 1960s and the early 1970s when the total accumulated investment was less than USD 6.0 billion, effects of investments became positive in 1973, the relationship between PG(BOD) and water quality returned to the similar conditions in the 1960s after the late 1990s, and (4) positive combined effects of the measures on the River BOD quality were about 10 mg-BOD l-1 in 2010. The methods are applicable for other river basins in the world to evaluate the effectiveness of water quality improvement measures.

Nitrogen Source Apportionment for the Catchment, Estuary, and Adjacent Coastal Waters of the River Scheldt

Vermaat, J. E., S. Broekx, B. Van Eck, G. Engelen, F. Hellmann, J. De Kok, H. Van der Kwast, J. Maes, W. Salomons, and W. Van Deursen. 2012. Nitrogen source apportionment for the catchment, estuary, and adjacent coastal waters of the River Scheldt. Ecology and Society 17(2): 30. https://doi.org/10.5751/ES-04889-170230

Long-Term Trends in Intertidal and Subtidal Benthic Communities in Response to Water Quality Improvement Measures

Long-term monitoring studies are needed to understand changes in ecosystem status when restoration measures are implemented. A long-term data series (1996–2007) of the Tagus estuary (Portugal) intertidal and subtidal benthic communities was collected in a degraded area where mitigation measures were implemented. Multivariate analysis was used to analyze spatial and temporal patterns in benthic community composition and trends in five benthic community metrics (i.e., taxonomic richness, density, biomass, Shannon–Wiener diversity and the AMBI index) were also examined. The results revealed a clear separation between intertidal and subtidal assemblages, although they had 50% of taxa in common, including the most abundant. Significant positive trends were found for all metrics showing that both intertidal and subtidal communities responded to the restoration measures implemented. Nevertheless, biotic indices need some adaptation before being universally applied to intertidal and subtidal habitats.

Evaluation of pollutant build-up and wash-off from selected land uses at the Port of Brisbane, Australia

The quality of stormwater runoff from seaports can be an important source of pollution to the marine environment. Currently, little knowledge exists with regards to the pollutant generation capacity specific to seaports as they do not necessarily compare well with conventional urban land use. The research project focussed on the assessment of pollutant build-up and wash-off. The study was undertaken using rainfall simulation and small impervious plots for different port land uses with the results obtained compared to typical urban land uses. The study outcomes confirmed that the Port land uses exhibit comparatively lower pollutant concentrations. However, the pollutant characteristics varied across different land uses. Hence, the provision of stereotypical water quality improvement measures could be of limited value. Particle size <150 μm was predominant in suspended solids. Therefore, if suspended solids are targeted as the surrogate parameter for water quality improvement, this particle size range needs to be removed.