Salt content of reclaimed water from sanitation facilities in informal settlements and management options for sustainable agricultural irrigation

2015 ◽  
Vol 10 (1) ◽  
pp. 99-109
Author(s):  
K. Müller ◽  
P. Cornel
Keyword(s):  
Water Reuse ◽  
Membrane Filtration ◽  
Root Zone ◽  
Tap Water ◽  
Salt Content ◽  
Reclaimed Water ◽  
Management Options ◽  
Urine Separation ◽  
Per Capita

For long-term sustainable irrigation of agricultural areas, salt accumulation on the fields needs to be controlled. In areas where rainfall is high at least during some time of the year, infiltrating water is usually sufficient to leach salts from the soil. In arid and semi-arid regions, rainfall might be too scarce, and additional measures for the removal of salts from the root zone are necessary. This paper presents data on water quantities, electrical conductivity (EC), and total dissolved solids (TDS) from a research project with agricultural water reuse in North Namibia and discusses options for salinity management. During planning, TDS were quantified using literature data. After implementation, quantities, EC, and TDS of tap water and reclaimed water were monitored. Mean water consumption is 61–64 L per capita equivalent and day. TDS loads are about 20–21 g/(capita equivalent × d) and thus lower than reported in literature. TDS loads in the water can be reduced by measures such as urine separation or reverse osmosis membrane filtration. However, accumulation on the field is still considerable in the long term. Salt uptake in crops is only substantial to the salt balance if TDS contents of the irrigation water are relatively low. Therefore, in the majority of cases, regular drainage and leaching of the fields are necessary. The per capita TDS loads and water quantities presented in this work are specific results collected from the facilities implemented in this project. They can serve as a basis for estimating water quantities and excreta loads for similarly managed sanitation facilities.

Production of high quality water for reuse purposes: the West Basin experience

2003 ◽  
Vol 3 (3) ◽  
pp. 167-175 ◽  
Author(s):  
V. Lazarova ◽  
P. Sheilds ◽  
B. Levine ◽  
P. Savoye ◽  
D. Hranisavljevic ◽  
...  
Keyword(s):  
Water Reuse ◽  
High Performance ◽  
Membrane Filtration ◽  
Salt Content ◽  
The West ◽  
Pilot Studies ◽  
Lime Pretreatment ◽  
Trace Organics ◽  
Main Challenge ◽  
West Basin

Water reuse is becoming an essential factor for developing sound water and environment managaement policies, The main challenge for the operators of water reuse facilities is to increase the cost-efficiency and reliability of water reuse systems. To achieve this objective, an R&D program has been implemented at the West Basin Recycling Plant in California to study the removal of trace organics by advanced treatment (UV disinfection, membrane filtration). The pilot studies demonstrated the efficiency of two UV systems for final disinfection and in particular its high performance for the MF/RO effluent at low UV doses. UV appears as a cost competitive alternative to chlorination; it prevents the generation of toxic chlorinated by-products and reduces the salt content. It was demonstrated that microfiltration, as a replacement of conventional lime pretreatment for reverse osmosis, also offers numerous advantages. Despite the improved removal of trace organics, the membrane pretreatment before RO leads to a saving of 45% of life costs.

Long-Range Planning for Water Reuse in the City of Los Angeles

1991 ◽  
Vol 24 (9) ◽  
pp. 11-17 ◽  
Author(s):  
Bahman Sheikh
Keyword(s):  
Los Angeles ◽  
Groundwater Recharge ◽  
Water Reuse ◽  
Potable Water ◽  
Reclaimed Water ◽  
Potable Reuse ◽  
Water Demands ◽  
San Fernando ◽  
Near Term

While new sources of affordable potable water for Los Angeles will likely decrease or be unavailable in the future, sources of readily usable reclaimed water will double over the next decade. For many non-potable uses (e.g., landscape irrigation, industrial cooling, toilet flushing), reclaimed water can replace potable water, thereby making equivalent volumes of potable water available. Groundwater recharge with reclaimed water can further augment potable water supplies in significant volumes. Quantitative goals for water reuse were derived by comparing projected water demands with predicted dependable supplies. These goals are to reuse 40, 70, and 80 percent of the total effluent by the years 2010, 2050, and 2090, respectively. In this planning study, several water reuse concepts were evaluated for near-, mid-, and long-term application. For the near-term, several immediately implementable water reuse projects are recommended, involving landscape irrigation, industrial cooling and groundwater recharge. For the mid-term, massive groundwater recharge in San Fernando Valley and in Central and West Coast Basins is recommended. For the long-term, potable reuse and/or groundwater recharge appear to be the best options.

scholarly journals Modelling Salinity and Sodicity Risks of Long-Term Use of Recycled Water for Irrigation of Horticultural Crops

Soil Systems ◽  
2021 ◽  
Vol 5 (3) ◽  
pp. 49
Author(s):  
Vinod Phogat ◽  
Dirk Mallants ◽  
Jirka Šimůnek ◽  
James W. Cox ◽  
Paul R. Petrie ◽  
...  
Keyword(s):  
Soil Solution ◽  
Crop Production ◽  
Root Zone ◽  
South Australia ◽  
Recycled Water ◽  
Management Scenarios ◽  
Management Options ◽  
Horticultural Crops ◽  
The Impact

Long-term use of recycled water (RW) for irrigation in arid and semiarid regions usually changes the soil solution composition and soil exchange characteristics, enhancing the risk for salinity and sodicity hazards in soils. This modelling study focuses on developing alternative management options that can reduce the potentially harmful impacts of RW use on the irrigation of wine grapes and almonds. The multicomponent UNSATCHEM add-on module for HYDRUS-1D was used to evaluate the impact of long-term (2018–2050) use of irrigation waters of different compositions: good-quality low-salinity (175 mg/L) water (GW), recycled water with 1200 mg/L salinity (RW), blended water of GW and RW in the 1:1 proportion (B), and monthly (Alt1) and half-yearly (Alt6) alternate use of GW and RW. The management options include different levels of annual gypsum applications (0, 1.7, 4.3, and 8.6 t/ha soil) to the calcareous (Cal) and hard red-brown (HRB) soils occurring in the Northern Adelaide Plain (NAP) region, South Australia. Additional management scenarios involve considering different leaching fractions (LF) (0.2, 0.3, 0.4, and 0.5) to reduce the salinity build-up in the soil. A new routine in UNSATCHEM to simulate annual gypsum applications was developed and tested for its applicability for ameliorating irrigation-induced soil sodicity. The 1970–2017 period with GW irrigation was used as a warmup period for the model. The water quality was switched from 2018 onwards to reflect different irrigation water qualities, gypsum applications, and LF levels. The data showed that the GW, B, Alt1, and Alt6 irrigation scenarios resulted in lower soil solution salinity (ECsw) than the RW irrigation scenario, which led to increased ECsw values (4.1–6.6 dS/m) in the soil. Annual gypsum applications of 1.7, 4.3, and 8.6 t/ha reduced pH, SAR, and ESP in both soils and reduced the adverse impacts of irrigation, especially in surface soils. A combination of water blending or cyclic water use with 3.8 t/ha annual gypsum applications showed promise for the SAR and ESP control. Additionally, irrigation with RW, a 0.2 LF, and annual gypsum applications limited the harmful salinity impacts in the soils. However, in the RW irrigation scenario, ECsw and ESP at the bottom of the crop root zone (90–120 cm depth) in the HRB soil were still higher than the wine grape and almond salinity thresholds. Thus, annual amendment applications, combined with the long-term use of blended water or cyclic use of RW and GW, represent a sustainable management option for crop production at the calcareous and hard red-brown soils.

Water reuse and integrated water resources management in Vitoria-Gasteiz, Spain

2008 ◽  
Vol 3 (2) ◽  
Author(s):  
R. Mujeriego ◽  
J. López
Keyword(s):  
Water Resources ◽  
Water Resources Management ◽  
Water Reuse ◽  
Flood Control ◽  
Reclaimed Water ◽  
Integrated Water Resources Management ◽  
Partial Substitution ◽  
Management Options ◽  
Resources Management ◽  
Essential Components

Water reclamation and reuse have become essential components of water resources management in Vitoria-Gasteiz, by helping to overcome historical water deficits experienced by the city with respect to water allocations set in 1973 with the Metropolitan Area of Bilbao, for the conjunctive use of the Urrunaga-Ullibarri reservoirs system. By generating a reliable flow of 35,000° m3/day of high quality reclaimed water, the options available for integrated water resources management have widely expanded as to allow in-stream river flow substitution, agricultural irrigation, seasonal storage of reclaimed water, and more favorable flood control policies for the Urrunaga-Ullibarri reservoirs system. Those management options have been made possible thanks to the implementation of an extensive and elaborated water distribution and storage system (reuse component) that allows distribution of reclaimed water to 10,000 ha of farmland, seasonal storage in a 7 hm3 reservoir, partial substitution of in-stream river water, and the potential consideration of water augmentation in reservoirs. The continuous support and promotion by agricultural users, the excellent operation and maintenance records of the project, and its favorable economic features have been instrumental in assuring a wide acceptance of this innovative water management option, under the Vitoria-Gasteiz social, economic, geographical and water resources conditions.

The Reproduction Vector of the Russian Economy: 1999-2007

2008 ◽  
pp. 94-109 ◽  
Author(s):  
D. Sorokin
Keyword(s):  
Economic Policy ◽  
Human Capital ◽  
Growth Rates ◽  
Developed Countries ◽  
Gdp Per Capita ◽  
Real Sector ◽  
Russian Economy ◽  
Per Capita ◽  
The Developed Countries

The problem of the Russian economy’s growth rates is considered in the article in the context of Russia’s backwardness regarding GDP per capita in comparison with the developed countries. The author stresses the urgency of modernization of the real sector of the economy and the recovery of the country’s human capital. For reaching these goals short- or mid-term programs are not sufficient. Economic policy needs a long-term (15-20 years) strategy, otherwise Russia will be condemned to economic inertia and multiplying structural disproportions.

STUDIES IN THE SUPPOSED GOITROGENOUS EFFECT OF TAP WATER IN HELSINKI

1960 ◽  
Vol XXXIII (IV) ◽  
pp. 630-636
Author(s):  
F.-E. Krusius ◽  
P. Peltola
Keyword(s):  
Tap Water ◽  
Physiological Saline ◽  
Normal Weight ◽  
The Body ◽  
Iodine Uptake ◽  
Redistilled Water ◽  
Detectable Difference ◽  
Term Administration ◽  
Long Term Experiment

ABSTRACT The study reported here was performed in order to examine the tap water of Helsinki for its alleged goitrogenous effect. In a short-term, 24-hour experiment with rats, kept on an iodine-poor diet, we noticed no inhibition of the 4-hour 131I uptake, as compared with that of animals receiving physiological saline instead of tap water. Two similar groups of rats receiving 1 and 2 mg of mercazole in redistilled water showed a distinct blockage of the 4-hour uptake, which proved the effect of this substance. In a long-term experiment of 5 weeks' duration there was no detectable difference in the body weight, thyroid weight and the 4-hour 131I uptake when the rats receiving tap water or distilled water to which 0.45 per cent of sodium chloride was added were compared with each other. Replacement of tap water by a 10 mg per cent solution of mercazole in redistilled water enlarged the thyroid to double its normal weight and increased the 131I uptake to approximately five times that of the controls. Thus our experiments failed to demonstrate any goitrogenous effect in the tap water of Helsinki. Changes similar to those produced by a long-term administration of mercazole, i. e. an enlargement of the thyroid and an increased thyroidal iodine uptake, have been shown to be due to milk collected from goitrous areas. The observations here reported confirm the importance of milk in the genesis of the goitre endemia of Helsinki. Attention is further called to the fact that a thyroidal enlargement combined with an increased thyroidal iodine uptake cannot always be taken as a sign of iodine deficiency because similar changes may be produced by the administration of goitrogens.

The Quantification of Structural Reforms in OECD Countries

2018 ◽  
Author(s):  
Balázs Égert ◽  
Peter Gal
Keyword(s):  
Product Market ◽  
Physical Capital ◽  
Oecd Countries ◽  
Market Regulation ◽  
Structural Reforms ◽  
Long Term Effects ◽  
Per Capita ◽  
Product Market Regulation ◽  
The Impact

This chapter describes and discusses a new supply-side framework that quantifies the impact of structural reforms on per capita income in OECD countries. It presents the overall macroeconomic impacts of reforms by aggregating over the effects on physical capital, employment, and productivity through a production function. On the basis of reforms defined as observed changes in policies, the chapter finds that product market regulation has the largest overall single policy impact five years after the reforms. But the combined impact of all labour market policies is considerably larger than that of product market regulation. The paper also shows that policy impacts can differ at different horizons. The overall long-term effects on GDP per capita of policies transiting through capital deepening can be considerably larger than the five- to ten-year impacts. By contrast, the long-term impact of policies coming only via the employment rate channel materializes at a shorter horizon.

scholarly journals Biofilm reduction potential of 0.02% polyhexanide irrigation solution in several types of urethral catheters

BMC Urology ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Florian H. H. Brill ◽  
Julia Hambach ◽  
Christian Utpatel ◽  
Diana C. Mogrovejo ◽  
Henrik Gabriel ◽  
...  
Keyword(s):  
Membrane Filtration ◽  
Saline Solution ◽  
Bacterial Biofilm ◽  
Plate Count ◽  
Vitro Assay ◽  
Significant Difference ◽  
Irrigation Solution ◽  
Clinically Relevant Bacteria

Abstract Background Long-term use of urethral catheters is associated with high risk of urinary tract infection (UTI) and blockage. Microbial biofilms are a common cause of catheter blockage, reducing their lifetime and significantly increasing morbidity of UTIs. A 0.02% polyhexanide irrigation solution developed for routine mechanical rinsing shows potential for bacterial decolonization of urethral catheters and has the potential to reduce or prevent biofilm formation. Methods Using an in vitro assay with standard market-leading types of catheters artificially contaminated with clinically relevant bacteria, assays were carried out to evaluate the biofilm reduction and prevention potential of a 0.02% polyhexanide solution versus no intervention (standard approach) and irrigation with saline solution (NaCl 0.9%). The efficiency of decolonization was measured through microbial plate count and membrane filtration. Results Irrigation using a 0.02% polyhexanide solution is suitable for the decolonization of a variety of transurethral catheters. The effect observed is significant compared to irrigation with 0.9% saline solution (p = 0.002) or no treatment (p = 0.011). No significant difference was found between irrigation with 0.9% saline solution and no treatment (p = 0.74). Conclusions A 0.02% polyhexanide solution is able to reduce bacterial biofilm from catheters artificially contaminated with clinically relevant bacteria in vitro. The data shows a reduction of the viability of thick bacterial biofilms in a variety of commercially available urinary catheters made from silicone, latex-free silicone, hydrogel-coated silicone and PVC. Further research is required to evaluate the long-term tolerability and efficacy of polyhexanide in clinical practice.

Economic considerations and decision support tool for wastewater reuse scheme planning

2007 ◽  
Vol 56 (5) ◽  
pp. 175-182 ◽  
Author(s):  
R. Hochstrat ◽  
D. Joksimovic ◽  
T. Wintgens ◽  
T. Melin ◽  
D. Savic
Keyword(s):  
Water Reuse ◽  
Net Present Value ◽  
Wastewater Reuse ◽  
Reclaimed Water ◽  
Decision Support Tool ◽  
Critical Issue ◽  
Economic Feasibility ◽  
Support Tool ◽  
The Cost ◽  
Economic Considerations

The reuse of upgraded wastewater for beneficial uses is increasingly adopted and accepted as a tool in water management. However, funding of schemes is still a critical issue. The focus of this paper is on economic considerations of water reuse planning. A survey of pricing mechanisms for reclaimed water revealed that most schemes are subsidised to a great extent. In order to minimise these state contributions to the implementation and operation of reuse projects, their planning should identify a least cost design option. This also has to take into account the established pricing structure for conventional water resources and the possibility of gaining revenues from reclaimed water pricing. The paper presents a case study which takes into account these aspects. It evaluates different scheme designs with regard to their Net Present Value (NPV). It could be demonstrated that for the same charging level, quite different amounts of reclaimed water can be delivered while still producing an overall positive NPV. Moreover, the economic feasibility and competitiveness of a reuse scheme is highly determined by the cost structure of the conventional water market.

Sign in / Sign up

Export Citation Format

Share Document