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The paper summarizes the experience gained with the ISS water management system during the missions ISS-1 through ISS-17 (since November 2, 2000, through October 23, 2008). The water supply sources and structure, consumption and supply balance and balance specifics at various phases of space station operation are reviewed. The performance data of the system for water recovery from humidity condensate SRV-K and urine feed and pretreatment system SPK-U in the Russian orbital segment are presented. The key role of water recovery on board the ISS and the need to supplement the station's water supply hardware with a system for water reclamation from urine SRV-U is emphasized. The prospects of regenerative water supply system development are considered.

Space Station Freedom (SSF) will be operational for up to 30 years with missions lasting up to 180 days. Because of the need for large amounts of potable and hygiene water for the crews, it will not be practical to supply water from the ground (as was done for Skylab) or to generate water from fuel cells (as is done for the Shuttle). Hence, waste and metabolic waters will be reclaimed and recycled in SSF. Because of the unique nature of the water sources and the closed loop recycling processes, providing safe water will be a challenging task. Developing a program for the verification of SSF water quality to ensure crew health is the responsibility of NASA's Medical Sciences Division at the Johnson Space Center (JSC). This program is being implemented through the Environmental Health System (EHS). This paper will describe the strategy for the development of water quality criteria and standards, and the associated monitoring requirements.

The ability of iodine to maintain microbial water quality in a simulated spacecraft water system is being studied. An iodine level of about 2.0 mg/L is maintained by passing ultrapure influent water through an iodinated ion exchange resin. Six liters are withdrawn daily and the chemical and microbial quality of the water is monitored regularly. Stainless steel coupons used to monitor biofilm formation are being analyzed by culture methods, epifluorescence microscopy, and scanning electron microscopy. Results from the first two years of operation show a single episode of high bacterial colony counts in the iodinated system. This growth was apparently controlled by replacing the iodinated ion exchange resin. Scanning electron microscopy indicates that the iodine has limited but not completely eliminated the formation of biofilm during the first two years of operation.

At the initial phase of the construction of the international space station (ISS) water supply will be provided by the systems located in the Russian segment. The paper reviews the systems for water recovery from humidity condensate and urine to be incorporated in the Russian segment of the ISS. The similar systems have been successfully operated on the Mir space station. The updates aim at enhancing system cost-effectiveness and reliability. The system for water recovery from humidity condensate (WRS-C) features an added assembly for the removal of organic contaminants to be catalytically oxidized in an air/liquid flow at ambient temperature and pressure. The system for water reclamation from urine (WRS-U) incorporates a new distillation subsystem based on vacuum distillation with a multistage rotary distiller and a vapor compression or thermoelectric heat pump. The updating of the WRS-C system will enable an increase in the multifiltration bed's life at least two fold.

The crews of Expeditions 12 and 13 aboard the International Space Station (ISS) continued to rely on potable water from two different sources, regenerated humidity condensate and Russian ground-supplied water. The Space Shuttle launched twice during the 12-months spanning both expeditions and docked with the ISS for delivery of hardware and supplies. However, no Shuttle potable water was transferred to the station during either of these missions. The chemical quality of the ISS onboard potable water supplies was verified by performing ground analyses of archival water samples at the Johnson Space Center (JSC) Water and Food Analytical Laboratory (WAFAL). Since no Shuttle flights launched during Expedition 12 and there was restricted return volume on the Russian Soyuz vehicle, only one chemical archive potable water sample was collected with U.S. hardware and returned during Expedition 12. This sample was collected in March 2006 and returned on Soyuz 11.

Phase separation is one of the most significant obstacles encountered during the development of analytical methods for water quality monitoring in spacecraft environments. Removing air bubbles from water samples prior to analysis is a routine task on earth; however, in the absence of gravity, this routine task becomes extremely difficult. This paper details the development and initial ground testing of liquid metering centrifuge sticks (LMCS), devices designed to collect and meter a known volume of bubble-free water in microgravity. The LMCS uses centrifugal force to eliminate entrapped air and reproducibly meter liquid sample volumes for analysis with Colorimetric Solid Phase Extraction (C-SPE). Previous flight experiments conducted in microgravity conditions aboard the NASA KC-135 aircraft demonstrated that the inability to collect and meter a known volume of water using a syringe was a limiting factor in the accuracy of C-SPE measurements.

Colorimetric-solid phase extraction (C-SPE) is being developed as a method for in-flight monitoring of spacecraft water quality. C-SPE is based on measuring the change in the diffuse reflectance spectrum of indicator disks following exposure to a water sample. Previous microgravity testing has shown that air bubbles suspended in water samples can cause uncertainty in the volume of liquid passed through the disks, leading to errors in the determination of water quality parameter concentrations. We report here the results of a recent series of C-9 microgravity experiments designed to evaluate manual manipulation as a means to collect bubble-free water samples of specified volumes from water sample bags containing up to 47% air. The effectiveness of manual manipulation was verified by comparing the results from C-SPE analyses of silver(I) and iodine performed in-flight using samples collected and debubbled in microgravity to those performed on-ground using bubble-free samples.

The paper summarizes the six years' experience gained with the ISS water management system during the missions ISS-1 through ISS-14 (since November 2, 2000 through October 31, 2006). The water supply sources, consumption structure and supply balance and balance specifics at various phases of space station operation are reviewed. The performance data of the system for water recovery from humidity condensate SRV-K and urine feed and pretreatment system SPK-U in the Russian orbital segment are presented. The key role of water recovery during space missions and the prospects of regenerative water supply of an interplanetary space station are discussed. The aim of this paper is to summarize the water supply experience and to provide recommendations for a perspective water supply integrated system based on water recovery.

Microbial proliferation in the STS potable water system is prevented by maintaining a 2-5 ppm iodine residual. The iodine is added to fuel cell water by an iodinated ion exchange resin in the Microbial Check Valve (MCV). Crew comments indicated excessive iodine in the potable water. To better define the problem, a method of in-flight iodine analysis was developed. Inflight analysis during STS-30 and STS-28 indicated iodine residuals were generally in the 9-13 ppm range. It was determined that the high iodine residual was caused by MCV influent temperatures in excess of 120 °F. This is well above the MCV operating range of 65-90 °F. The solution to this problem was to develop a resin suitable for the higher temperatures. Since 8 months were required to formulate a MCV resin suitable for the higher temperatures, a temporary solution was necessary. Two additional MCV's were installed on the chilled and ambient water lines leading into the galley to remove the excess iodine.

On the International Space Station (ISS), atmospheric humidity condensate and other waste waters will be recycled and treated to produce potable water for use by the crews. Space station requirements include an on-orbit capability for real-time monitoring of key water quality parameters, such as total organic carbon, total inorganic carbon, total carbon, pH, and conductivity, to ensure that crew health is protected for consumption of reclaimed water. The Crew Health Care System for ISS includes a total organic carbon (TOC) analyzer that is currently being designed to meet this requirement. As part of the effort, a spacecraft TOC analyzer was developed to demonstrate the technology in microgravity and mitigate risks associated with its use on station. This analyzer was successfully tested on Shuttle during the STS-81 mission as a risk mitigation experiment. A total of six ground-prepared test samples and two Mir potable water samples were analyzed in flight during the 10-day mission.

The primary source of potable water planned for the International Space Station will be generated from the reclamation of humidity condensate, urine, and hygiene waters. It is vital to crew health and performance that this reclaimed water be safe for human consumption, and that health risks associated with recycled water consumption be identified and quantified. Only recently has data been available on the chemical constituents in reclaimed waters generated in microgravity. Results for samples collected during Mir-21 reveal that both the reclaimed water and stored water are of potable quality, although the samples did not meet U.S. standards for total organic carbon (TOC), total phenols, and turbidity.

This report describes the first two parts of a three-phase project to develop and test a spacecraft-compatible capillary electrophoresis (CE) instrument. This instrument is designed to monitor the quality of recycled potable water aboard spacecraft such as the International Space Station. Phase I involved selecting and validating methods for low mass-to-charge ratio (m/z) cations and anions by using a slightly modified commercial CE instrument as a model. The analytical performance of several published CE methods was assessed for their ability to detect targeted anions and cations listed in a NASA water quality standard. Direct and indirect UV absorption detection at a single wavelength (214 nm) was used, and separation selectivity and sensitivity were optimized at the expense of analysis time. Phase II focused on building a breadboard CE instrument and flight-testing it on NASA's KC-135 parabolic aircraft.

To satisfy a requirement to supply water to Mir station, a process for treating iodinated water on the Shuttle was developed and implemented. The treatment system consists of packed columns for removing iodine and a syringe-based injection system for adding ionic silver, the biocide used in Mir water. Technical and potable grade water is produced and transferred in batches using collapsible 44-liter contingency water containers (CWCs). Silver is added to the water via injection of a solution from preloaded syringes. Minerals are also added to water destined for drinking. During the previous four Shuttle-Mir docking missions a total of 2781 liters (735 gallons) of water produced by the Shuttle fuel cells was processed using this method and transferred to Mir. To verify the quality of the processed water, samples were collected during flight and returned for chemical analysis.

The paper presents the results of ground and flight (on OSS Mir) tests of an updated purification assembly of the WRS-C system outfitted with a filter-reactor. The tests have proved that the filter-reactor oxidizes effectively basic organic contaminants in humidity condensate including ethyleneglycol to ones that easily undergo sorption, enables the operation of the recovery system in the event of an off-design increase in organic contaminants in condensate and significantly improves the lifetime of the purification assembly. The data obtained confirm a wise selection of the purification assembly hardware for the system for water recovery from humidity condensate WRS-CM for the ISS service module.

A selection of a distillation subsystem with a rotary multistage vacuum distiller (RMVD) and a heat pump (HP) for the system for water reclamation from urine for the international space station is substantiated. The results of computational/experimental analysis of specific energy for distillation with RMVD and HP of different type used are presented. The test results of an experimental system mockup are given. It is shown that the subsystem of a given type is stable in operation, features high condensate processing rate and low specific energy demand.

Archival sampling of potable water and condensate for ground laboratory analysis has been an important part of the Shuttle-Mir program because of coolant leaks and other events on Mir that have affected water quality. We report here the development of and preliminary results from a novel device for single phase humidity condensate collection at system pressures. The sampler consists of a commercial-off-the-shelf Teflon® bladder and a custom reinforced Nomex® restraint that is sized properly to absorb the stress of applied pressures. A plastic Luer-Lock disconnect, with poppet actuated by a mating Luer-Lock fitting, prevents the contents from being spilled during transport. In principle, a sampler of any volume can be designed. The empty mass of the reusable one-liter sampler is only 63 grams. Several designs were pressure tested and found to withstand more than 3 atmospheres well in excess of typical spacecraft water or wastewater system pressures.

Liquid Chromatography / Mass Spectrometry / Mass Spectrometry (LC/MS/MS) is a powerful technique for identifying unknown non-volatile organic compounds dissolved in liquids. One type of LC/MS/MS that is gaining popularity is quadrupole-time-of-flight (QqTOF) mass spectrometry. This technique is now in use at the Johnson Space Center for identification of unknown nonvolatile organics in water samples from the space program. An example of the successful identification of an unknown peak in U.S. Lab Condensate is reviewed in detail in this paper. Each step of the procedure is described in the identification of triethylene glycol mono-n-butyl ether (TGBE) as the unknown analyte. The advantages of time-of-flight instrumentation are demonstrated through this example as well as the strategy employed in using time-of-flight data to identify unknowns. The use of the instrument for quantitative analysis is also demonstrated.

The paper summarizes the experience gained on the ISS water management system during the missions of ISS-1 through ISS-16 (since November 2 2000, through December 31, 2007). The water supply sources and structure, consumption and supply balance at various phases of space station operation are reviewed. The performance data of the system for water recovery from humidity condensate SRV-K and urine feed and pretreatment system SPK-U in the Russian orbital segment are presented. The key role of water recovery on a board the ISS and the need to supplement the station's water supply hardware with a system for water reclamation from urine, water from a carbon dioxide reduction system and hygiene water is shown.

The Crew Health Care System (CHeCS) is responsible for providing environmental monitoring to protect crew health, including in-flight chemical water quality analysis. To meet this objective, Total Organic Carbon Analyzer (TOCA) Serial Number (SN) 1002 was launched to the International Space Station (ISS) in April of 2001 as part of the CHeCS hardware. Since that time it has been used to evaluate the quality of the potable water supplies consisting of reprocessed atmospheric condensate water, Shuttle-transferred water, and ground-supplied water. Potable water is available for crew use from the Service Module System for Regeneration of Water from Condensate (SRV-K) galley hot and warm ports and the Stored Potable Water System (SVO-ZV) port. Potable water samples are periodically collected from each of these ports for in-flight analysis with the TOCA.

The International Space Station (ISS) drinking water supply consists of water recovered from humidity condensate, water transferred from Shuttle, and groundwater supplied from Russia. The water is dispensed from both the stored water dispensing system (SVO-ZV) and the condensate recovery system (SRV-K) galley. Teflon bags are used periodically to collect potable water samples, which are then transferred to Shuttle for return to Earth. The results from analyses of these samples are used to monitor the potability of the drinking water on board and evaluate the efficiency of the water recovery system. This report provides results from detailed analyses of samples of ISS recovered potable water, Shuttle-supplied water, and ground-supplied water taken during ISS Expeditions 4 and 5. During Expedition 4, processing of U.S. Lab condensate through the Russian condensate recovery system was initiated. Results indicate water recovered from both Service Module and U.S.