Implications of de Facto Reuse on Future Regulatory Developments for Beaufort-Jasper Water & Sewer Authority in Okatie, South Carolina, USA

A significant portion of the national water supply can be attributed to de facto or unplanned potable reuse, though the extent of its contribution is difficult to estimate. Fortunately, the contribution of Water Resource Recovery Facility (WRRF) effluent to waters that supply drinking water treatment plants has been documented by some communities. In the United States (US), among the top 25 most impacted drinking water treatment plants by upstream WRRF, 16% of the influent flow to the drinking water treatment plant under average streamflow and up to 100% under low-flow conditions is WRRF effluent. Currently, the full extent of de facto reuse in the US may be much higher because of population growth. The scenario is no different for Beaufort-Jasper Water and Sewer Authority (BJWSA) in South Carolina, US, with contributions to the Savannah River originating from numerous WRRF and other upstream dischargers. South Carolina coastal utilities such as BJSWA are considering direct and indirect potable reuse options, driven by disposal limitations and challenges. Currently, South Carolina does not have a framework, guidelines, or regulations for reuse, but discussions have started among the regulated community. In addition to understanding the extent of de facto reuse, the state will need to develop standards and best practices to enable future adoption of planned potable reuse solutions to water resources challenges. Such guidance should address human health risk management and technical considerations regarding treatment in addition to other factors, including source control, storage, fail-safe operation, monitoring, non-cost factors, and public acceptance. This study conducted a mapping assessment specific to BJWSA, sampled at four locations on Savannah River, and observed that de facto reuse is approximately 4.6% to 5.9% during low-flow months and is within the range generally observed nationwide. When coupled with evidence that planned potable reuse can improve human health and environmental risks, this practice is a meaningful option in the water supply portfolio for many utilities.

Performance of a Horizontal Flow Constructed Reed Bed Filter for Municipal Wastewater Treatment: The Case Study of the Prototype Installed at Gaston Berger University, Saint-Louis, Senegal

In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability.

Study of Wastewater Advanced Treatment and Reclaimed Water Reuse for a Large General Hospital

A combined process of biological aerated filter,fiber ball filter and chlorine dioxide disinfection was used to treat effluent of primary hospital wastewater in Jinan.Its treatment capacity was designed as 400m^3/d based on the reclaimed water demand of the large general hospital.The quality of the effluent can meet the requirements of the Reuse of Urban Recycling Water——Water Quality Standard for Urban Miscellaneous Water Consumption(GB/T18920-2002).The project has less site area,low investment and operation cost and high automatic control level,so it can provide scientific references for design and operation of similar projects.

Potential contributions to Beijing's water supply from reuse of storm-and greywater

In order to find new approaches to alleviating the water crisis in Beijing which is caused by among others dwindling precipitation and rapid growth of population and manifests in a rapidly declining groundwater table this study explores decentralized stormwater harvesting and greywater reuse at household level as a means to reduce groundwater abstraction and water transfer from other regions.Based on a desktop case study two concepts for combined harvesting and reusing of storm-and greywater are presented.With rough pre-assumptions calculations show that a saving of 67.8%of tap water consumption can be achieved with the upgrading concept compared with 5.9% with the simple downgrading concept.The saving with the upgrading concept equals 0.545 ×109 m3 annual water volume if 20 million Beijing people apply this approach.Despite numerous prerequisites such as water treatment technology space demand energy and cost and public acceptance this paper advocates combining stormwater harvesting and greywater reuse in households with other measures for Beijing’s sustainable water management.

Simultaneous synthesis of heat-integrated water networks by a nonlinear program:Considering the wastewater regeneration reuse

Heat-integrated water network synthesis(HIWNS)has received considerable attention for the advantages of reducing water and energy consumptions.HIWNS is effective in water and energy sustainability.Mixed integer non-linear programming(MINLP)is usually applied in HIWNS.In this work,a novel nonlinear programming(NLP)was proposed for HIWNS by considering wastewater reuse and wastewater regeneration reuse.Integer variables are changed to non-linear equation by the methods for identifying stream roles and denoting the existence of process matches.The model is tested by examples with single and multiple regeneration unit problems.The testing results showed that the NLP is an alternative method for HIWNS with wastewater reuse and regeneration reuse.

Assessment of Wastewater Reuse in Kuwait and Its Impact on Amounts of Pollutants Discharged into the Sea

Kuwait has recently implemented a vigorous campaign that aims to reclaim and reuse all treated wastewater in an at- tempt to alleviate water scarcity problem and to preserve seawater quality. This paper assesses the present status of wastewater treatment, reclamation and reuse in Kuwait, and discusses the impact of wastewater reuse on the amounts of pollutants discharged into the sea. Through analysis of the historical records of the wastewater treatment plants, it has been found that reuse of reclaimed wastewater in Kuwait has greatly reduced the amounts of pollutants discharged into the sea. Results showed that more than 50% reduction in volumes of wastewater discharged into the sea had been achieved from year 2000 to year 2010. However, this study has predicted that the amounts of wastewater discharged into the sea will start increasing again by the year 2020 due to shortages of storage capacity for reclaimed wastewater and due to the limitation of wastewater reuse applications to basically agricultural and landscape irrigations. In contrary, the on-going works and future plans of the Ministry of Public Works (MPW) are expected to overcome this problem and lead to a zero discharge of wastewater into the sea.

Research of Water Quality Analysis,Treatment and Reuse Technology for Rainwater on the North University Campus

The pollution situation of different underlying surface and the change rule of each water quality index were researched,on the basis of rainwater quality monitoring by different approaches in a university campus. The results showed that due to some factors,such as the underlying surface material pollution,road materials,road surface pollution condition and surrounding atmospheric environment quality,the pollution of different underlying surface rainwater would be different. Main pollutants of rainwater runoff in the city campus area were such as COD,SS,NH;-N,TP,etc. Ultimately,along with the increase of accumulated rainfall,the pollutants tended to gradually decrease. The road rain pollution was more serious than roof runoff pollution and the early rain pollution was serious,but the late rain water quality was much better. According to the rainwater conditions,subsequent rainwater recycling technology and processing technology were determined as a way to alleviate the problem of water shortage and water pollution.

Reuse rate of treated wastewater in water reuse system

A water quality model for water reuse was made by mathematics induction. The relationship among the reuse rate of treated wastewater（R）, pollutant concentration of reused water（ Cs ）, pollutant concentration of influent（ C0）, removal efficiency of pollutant in wastewater（ E）, and the standard of reuse water were discussed in this study. According to the experiment result of a toilet wastewater treatment and reuse with membrane bioreactors, R would be set at less than 40%, on which all the concerned parameters could meet with the reuse water standards. To raise R of reuse water in the toilet, an important way was to improve color removal of the wastewater.

A Grey Water Dam Design for the Treatment and Reuse of Grey Water from Single and Multiple Households

An innovative design for the treatment and reuse of grey water is presented in the form of a grey water dam which is an outgrowth of the vertical grey water tower. A hydraulic equation has been formulated and is presented in this paper which is used to determine the seepage path within the grey water dam, and determine the dimensions of the dam components. The hydraulic equation model also helps in avoiding soil piping problems by keeping the phreatic line within the grey water dam. Vegetables are planted around the surface of the dam as a reuse option while helping recycling of water in the form of evapotranspiration. A successful pilot trial of this dam was run in Mnyamatsini area in Swaziland which can accept grey water from multiple households.

Treatment of submerged hollow fiber ultrafiltration membrane for reuse of sludge water

To lower the costs of wastewater treatment, the submerged hollow fiber ultrafiltration membrane was employed to reuse the filter backwash water and settling tank sludge water. Experimental study indicates that the submerged hollow fiber uhrafihration membrane can condense the concentration of sludge from 0. 1% -0. 3% to 2.5%. At 20 ℃, the system can operate continuously for 80 clays with daily online backwashing with chemical additions only once, and the membrane flux can be recovered up to 97% by using NaClO and NaOH as chemical additions. The results show that the membrane flux is mainly affected by temperature,and has a positive lin- ear relation to temperature with a slope of 0. 368. After treated by submerged hollow fiber uhrafihration membrane, the effluent can reach the National Standard for Drinking Water（ GB5749 -85 ） , especially for the sludge water from sedimentation tanks and the backwashing Water from filters in water supply plants.

The Possibility of Agricultural Drainage Water Reuse in Agricultural Project

Agricultural drainage water in Ashkada-Barak agricultural project is a major source of wasted water, which amount to about 35 million liters per day. This huge sum of wasted water cause a formation of pools around the area and therefore a lot of environmental problems such as the proliferation of mosquitoes, and other health problems, while it can be reuse in a variety purposes such as agriculture, fish farming and drinking, so the goal of this research is to study quality of water and determine its suitability. Different samples were taken over a period of year for testing the most important elements of which were estimated concentrations of nitrate, nitrite and ammonia. The results show a presence of high concentrations of nitrogen compounds in studied water. Temperature had been identified as environmental factor dynamically controlled the process of nitrification.

Research on optimal design of wastewater reclamation and reuse for a university

An optimal design of wastewater reuse for a University is concerned in this paper. The raw water and the capacity of wastewater reuse were determined according to the wastewater characteristic of a university; the treatment process was chosen by building a cost-benefit model; and the modeling test was performed about the operation effect of the proposed project and the recommended water quality of reclaimed water. It is estimated that 3.4×10^5 m^3/a tap water and 6.1×10^5 Yuan/a will be saved if the project was put into operation and the proposed project will reduce the total quantity of pollutant efficiently and bring lots of social and economic benefits.

Urban Rejected Water Reuse in Agriculture for Irrigation in Major Cities of India:A Synoptic Review

Indiscriminate and rapid urbanization without sufficient infrastructure to manage huge domestic sewage(urban rejected water)generated by urban centers posing serious threats to different ecosystems in many places across the world.On the other hand,the downstream of urban centers facing an acute shortage of water for irrigation.In recent years reuse of urban waste water is being increased in many countries including India irrespective of adverse impacts on other ecosystems.The present study has provided a synoptic review on urban rejected water reuse for irrigation in the major cities of India with a special focus on banks of the Musi river basin in South India where huge wastewater irrigation is being practiced in the world in comparison with global waste water irrigation practices.In all the cases major contaminants namely fecal coliform,nitrates,Biological Oxygen Demand(BOD),Chemical Oxygen Demand(COD)and Dissolved Oxygen(DO)are found in water and with increased soil and groundwater salinity on long term use.The review indicated that there a large scope to intensify the irrigation with proper treatment of wastewater.The study also suggested to understand the impacts of rejected water reuse impact on soil-water-food chain and also emphasizes the need for the establishment of sufficient ETPs to minimize the adverse impacts and also to protect hydro-agro ecosystems.

Emerging R&D on membranes and systems for water reuse and desalination

Sustainable production of clean water is a global challenge.While we firmly believe that membrane technologies are one of the most promising solutions to tackle the global water challenges,one must reduce their energy consumption and fouling propensity for broad sustainable applications.In addition,different membranes face various challenges in their specific applications during long-term operations.In this short review,we will summarize the recent progresses in emerging membrane technologies and system integration to advance and sustain water reuse and desalination with discussion on their challenges and perspectives.

Sustainable graywater reuse for residential landscape irrigation-a critical review

The demand for potable water is rising rapidly due to an ever-increasing population,economic activities,and dwindling water supplies.To provide adequate water supplies in the future,understanding the issues and challenges in the reuse of water and developing appropriate strategies for reuse will be critical.One way to augment water supplies for residential use is to reuse graywater- the wastewater from kitchens,bathrooms,and laundries.In this article,we critically review the evolution of water reuse,the definition of graywater,graywater reuse practices,volumes and flow in different situations,and graywater characteristics.We then examine the issues associated with different graywater treatment methods and how using graywater for irrigation around homes affects soil quality and plant growth.The study concludes that graywater treatment costs,human health risks,and its effect on soil quality are some of the challenges that need to be addressed in the future for widespread and sustainable reuse of graywater for irrigation around homes.

Gray Water Measurement and Feasibility of Retrieval Using Innovative Technology and Application in Water Resources Management in Isfahan-Iran

Reuse of wastewater for agriculture and green spaces purposes is significant.A mean yearly precipitation in Esfahan is 150 mm.The drinking water and agriculture usually used underground resources in the city.Gray water recycling is known as a suitable option today.Delivering all the water requirements of a home from refined water rises the cost of water.Whereas the essential water quality for garden,toilet and irrigation is less than drinking water.Therefore,the aim of this study is to analyze the evaluation of gray water and estimate the amount of recycle gray water which can use for drinking water with innovation method in Esfahan region in Iran.Previous studies did not measure the value of recycling gray water with new method of waste water treatment that can use for drinking purpose.In this study,gray water in Esfahan city is measured and technical aspects of its recycling is examined.Because of the lack of referable guidelines and official technical reports,studies from other similar countries applied in this study and on the basis of which the amount of recoverable gray water was calculated.Evaluations indicates that the overall recovery of gray water in Esfahan saves nine million cubic meters of water.The price of the rial of this value established on water is 190 billion Rials.Given the lack of water sources in Esfahan,the recycle of gray water seems to be a good option,however more research is required to select a recovery strategy.

Water shortage and wastewater reuse

China is not abandantly supplied with freshwater. Water shortage is a crucial problem in northern China, and affects the development of economy and causes a host of environmental and ecological problems. Water saving, water resource protection, strengthening of management and exploitation of new water resources are some of the major measures for solving the water shortage problem. Wastewater reuse is also a feasible and practical means of alleviating the problem.

Renovated water reuse for rapid infiltration system

The renovated water in the rapid infiltration system (RI) as area for fish and duck farming is feasible. The flesh of fish and duck is edible. The farming of fish for 5 months and duck for 120 - 130 days can be accepted. It is beneficial to environment and economy, especially in developing countries. The production of fish and duck can make up for the cost of wastewater treatment.

CAS-based Water Resources Optimal Allocation and Dynamic Simulation for Sewage Irrigation Area

Based on the theory of complex adaptive system(CAS),the optimal allocation model of water resources in sewage irrigation areas was established,which provided new ideas and application value for the rational utilization of agricultural production and waste water resources.The results demonstrated that the difference of crop energy capture mainly depended on the development stage.Waste water with a certain concentration was able to promote crop growth,while excessive concentration inhibited crop growth.The correlation between water absorption rate and leaf area index was close(R=0.9498,p<0.01).The amount of bad seeds increased at a speed of 34.7·d^-1,when system irrigated randomly in the seedling stage,while it tended to remain stable at a speed of 0.3·d^-1 after plants entering the mature stage which impacted the total yields of crops.

Evaluation of the exploitation of nontraditional water resources—Case study of Yantian District in Shenzhen

Yantian District in Shenzhen is a water deficient area. Water shortage has become a major obstacle to its further economic progress. Consequently, rational exploitation of nontraditional water resources(NWR)has been naturally adopted to increase local available water volume. The purpose of this paper is to analyse the exploitation of two kinds of NWR, namely wastewater reuse and seawater utilization, in Yantian District, and assess the contribution of each mode to deal with the water crisis. Two different nontraditional water supply systems respectively based on the reclaimed water and sea water were presented, and the effects of each system were evaluated in terms of technology, economy and environment. The result shows that both wastewater reclamation and reuse (WRR) and direct utilization of seawater (DUS) are of great importance to cope with the tight water resource situation in the district. The data indicate that the fresh water saved by WRR system and DUS system is 29 and 17 million m3/a respectively. Moreover, the BOD, COD, NH3-N and T-P reduced by the WRR system are 870, 2900, 725 and 87 t/a, respectively. Considering the integrated effectiveness, the development of WRR system, which is of specific significance to exploiting new water resource and save natural fresh water supplied from distant water diversion project, is the preferred methods used to solve the water shortage problem in Yantian District and recover the water environment as well as maintain the sustainable development of the city zone.