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Phosphorus (P) is an essential element for sustaining human life, but its current management is unsustainable. Scientists are currently developing novel scientific and technological innovations to improve P management. By engaging stakeholders to understand their perceptions and concerns, researchers can address concerns and improve the chances that their innovations will be adopted. In this paper, we conducted thirty-seven interviews with U.S. stakeholders to develop three case studies of technologies in P recovery. The cases investigated are i) urine diversion for P recovery, ii) biological P removal from wastewater, and iii) analysis of stable isotopes for source tracking in natural water bodies. Stakeholders highlighted an array of economic, regulatory, and social barriers to adoption that were similar across all three cases. The findings presented in this study provide proof of concept for the efficacy of comparative methods to identify shared challenges in adoptions of new innovations within a research area. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is a finite resource and necessary nutrient for agriculture. Urine contains a higher concentration of P than domestic wastewater, which can be recovered by source separation and treatment (hereafter urine diversion). Commercial and institutional (CI) buildings are a logical location for urine diversion since restrooms account for a substantial fraction of water use and wastewater generation. This study estimated the potential for P recovery from human urine and water savings from reduced flushing in CI buildings, and proposed an approach to identify building types and community layouts that are amenable to implementing urine diversion. The results showed that urine diversion is most advantageous in CI buildings with either high daily occupancy counts or times, such as hospitals, schools, office buildings, and airports. Per occupant P recovery benchmarks were estimated to be between 0.04–0.68 g/cap·d. Per building P recovery rates were estimated to be between 0.002–5.1 kg/d, and per building water savings were estimated to be between 3 and 23 % by volume. Recovered P in the form of phosphate fertilizer and potable water savings could accrue profits and cost reductions that could offset the capital costs of new urine diversion systems within 5 y of operation. Finally, urine diversion systems can be implemented at different levels of decentralization based on community layout and organizational structure, which will require socioeconomic and policy acceptance for wider adoption.

The deposition of solid phosphorus-based mineral particles is a common problem in urine diversion systems, which occurs in transport systems, particularly in horizontal pipelines. In this work, particle deposition behaviour in turbulent flow in a 3D horizontal pipe was simulated by using the Euler–Lagrange method. The effects of particle diameter, particle density, particle shape factor and fluid flow velocity on particle deposition behaviour were investigated. The results showed that the deposition rate increased by 9.92%,6.88% and 6.88% with increasing particle diameter (10-90 μ m ), particle density (1400 kg/m3–2300 kg/m3), and particle shape factor (0.2–1), respectively. For particles with larger diameters (>90 μ m ) or larger density (>2300 kg/m3), the deposition rate of these particles was almost reached 100%. It was found that gravitational sedimentation was the dominant deposition mechanism in low fluid flow velocity range (0.1–0.5 m/s). As fluid flow velocity increased (>0.5 m/s), turbulent fluctuation became the dominant factor that affected particle motion behaviour, whereas the effect of gravitational sedimentation on particle deposition behaviour declined significantly, and the increase in fluid flow velocity no longer significantly affects deposition rate. It was found that the deposition rate decreased by 29.13% as the fluid flow velocity was increased from 0.1 m/s to 0.5 m/s, while the corresponding deposition rate only decreased by 14.24% when the fluid flow velocity was increased from 0.5 m/s to 2 m/s. The optimal flow velocity was found to range between 0.75 and 1.25 m/s, which may mitigate the deposition of mineral solids in urine diversion systems. [ABSTRACT FROM AUTHOR]

Urine diversion (UD) is a system-of-systems that involves source separation of waste to maximize recovery of valuable nutrients, including phosphorus. Recent research shows how UD systems offer valuable ecological benefits and can aid in water conservation efforts, and public perception studies suggest that UD systems are generally viewed positively by end-users and the general public. Nevertheless, adoption and implementation of this promising sustainability solution remains limited in many countries, including the United States (U.S.). In this perspective, we argue that in order to scale up adoption in the U.S., UD researchers and innovators must do more to address regulatory barriers. We draw on insights from political science research on ‘regulatory regimes’ to introduce the array of regulations that apply to UD systems, with a focus on commercial and institutional buildings. We examine regulatory regimes all along the UD system-of-systems, beginning at the point of collection and ending at the point of beneficial reuse. We then propose next steps to address current regulatory challenges that impact adoption, with an emphasis on the importance of stakeholder coordination. Throughout, we argue that law and regulation plays a critical role in shaping adoption of UD technologies because: (1) different regulatory regimes will be important at different points in the system-of-systems, (2) there may be multiple regulatory regimes that apply to a single subsystem, and (3) it is important to consider that legal and regulatory definitions of a technology may not match scientific understanding.

Although Sweden pioneered in the development of resource-recovery sanitation solutions, and there has existed a political awareness of such solutions since the 1990s, their implementation has been slow. We adopt a historical (40-year) perspective and use the main journal of the Swedish sanitation sector as source material to go into depth why this has been the case. Central explanations emerge in terms of previously strong governmental control and continuously tightened environmental requirements that ceaselessly have expanded and strengthened the large-scale centralized sanitation system. In parallel, the sector has continuously been reminded of the shortcomings of alternative (and smaller) solutions and of the tension between recovery and treatment/risk management. The study highlights the possibility of achieving long-term and profound impacts from policy mixes, as well as the strong influence of the sum of challenges and choices over a long time, on today's perspectives and propensity for change. [ABSTRACT FROM AUTHOR]

In the case of advanced stage gynecological disorders, most patients have a disturbance in the upper urinary tract. Most patients with uterine cervical carcinoma are already in stage 3B and require urine diversion. The purpose of this study is to find and determine the profile of gynecological disorders that require urine diversion, the type of urine diversion, and urine diverted output in patients with cervical carcinoma. This descriptive analytical retrospective study was conducted at Dr. Soetomo Hospital, Surabaya, Indonesia, between 2012 and 2015. The samples of this study were all patients with gynecological disorders who underwent retrograde DJ stent procedures, underwent ureterocutaneostomy and nephrostomy at the Integrated Central Surgery Building, Dr. Soetomo Hospital, Surabaya, for three years between 2012 and 2015. Data was collected based on the medical record number of patients with gynecological disorders who underwent urine diversion procedures and were recorded in the book on the operation schedule. We find that the most common cause of gynecological abnormalities in kidney obstruction is cervical carcinoma. There are three types of urine diversions used, namely DJ stent, percutaneous nefropyelostomy, and ureterocutaneostomy, with DJ as the most commonly performed. Urine diversion can improve creatinine without being influenced by the type of diversity.

Prior measurements at bench scale revealed that waterless urinal cartridges containing oily sealant fluids are capable of partitioning pharmaceuticals from urine and therefore reducing their concentration in wastewater. We sought to measure pharmaceutical removal from in‐use waterless urinals. We developed a method to quantify pharmaceuticals in the sealant phase, which resulted in 79 ± 30% and 71 ± 30% recovery of eight pharmaceuticals from two sealant fluids, respectively. The method was applied to sealant samples collected over three weeks from in‐use waterless urinals on a university campus. Six of eight pharmaceuticals were present in the sealant samples from 1.4 µg/L to 241 µg/L. Loads of the six pharmaceuticals detected in the sealants were removed from the receiving wastewater from 0.02 µg/day to 3.4 µg/day across the sampling period. The concentration of the pharmaceuticals were similar over time, indicating rapid saturation and washout of the sealant. We also observed relatively rapid loss of sealant at maintenance intervals consistent with the manufacturer's instructions. These findings indicate that while waterless urinals do remove some pharmaceuticals from the wastewater stream, meaningful changes to wastewater concentrations will only result if the sealant fluid and/or the urinal cartridge are significantly modified. Practitioner points: We developed a quantification method for pharmaceuticals in oily waterless urinal sealants.Pharmaceuticals were present at relatively low concentrations in the sealant phase of two in‐use waterless urinals.We identify engineering challenges that must be overcome to meaningfully reduce pharmaceutical loads in wastewater with waterless urinals. [ABSTRACT FROM AUTHOR]

Since March 2014, a sustainably focused community located on a 0.7 hectares site in Portland, Oregon, USA, has been undertaking an experimental composting toilet system modeled after the Water Efficiency and Sanitation Standard (WE-Stand) set out by the International Association of Plumbing and Mechanical Officials (IAPMO). This system collects urine and hot composts human excreta in a dry-composting toilet system for eventual use on the community's organic gardens. The system design reduces the need to access municipal water, sewer, and electrical infrastructure, enhancing emergency preparedness. It conserves an otherwise wasted nutrient flow, and safely produces a valuable compost. The system consists of urine collection vessels, multiple portable collection containers for excreta, toilet paper, and additive, and a compost processor. Urine diversion has allowed the community to reclaim nitrogen and other nutrients otherwise lost in conventional sewage systems, resulting in large savings of potable water and significant carbon sequestration via topsoil creation. Logs showed thermophilic compost temperatures. Compost and urine pathogen testing met American National Standards Institute and National Sanitation Foundation Standard 41 requirements.

Phosphorus (P) is a finite resource and necessary nutrient for agriculture. Urine contains a higher concentration of P than domestic wastewater, which can be recovered by source separation and treatment (hereafter urine diversion). Commercial and institutional (CI) buildings are a logical location for urine diversion since restrooms account for a substantial fraction of water use and wastewater generation. This study estimated the potential for P recovery from human urine and water savings from reduced flushing in CI buildings, and proposed an approach to identify building types and community layouts that are amenable to implementing urine diversion. The results showed that urine diversion is most advantageous in CI buildings with either high daily occupancy counts or times, such as hospitals, schools, office buildings, and airports. Per occupant P recovery benchmarks were estimated to be between 0.04-0.68 g/cap·d. Per building P recovery rates were estimated to be between 0.002-5.1 kg/d, and per building water savings were estimated to be between 3 and 23 % by volume. Recovered P in the form of phosphate fertilizer and potable water savings could accrue profits and cost reductions that could offset the capital costs of new urine diversion systems within 5 y of operation. Finally, urine diversion systems can be implemented at different levels of decentralization based on community layout and organizational structure, which will require socioeconomic and policy acceptance for wider adoption., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Treavor Boyer is an editor at Water Research X., (© 2024 The Authors. Published by Elsevier Ltd.)

Decentralized treatment of wastewater has been identified as an area of growth for cyber-enabled sensing and control. One such system that would benefit from embedded cyber components is urine diversion. This research sought to create a cyber-physical system for wastewater collection and treatment. Two subsystems were integrated into the CPS: sensing and actuation. Real-time sensing using low-cost pH and conductivity sensors was used to monitor urine chemistry. Actuation was used to deliver urine to the system and to control urine chemistry. Once integrated, the system used the sensing data to determine when to actuate urine chemistry control pumps. By using urine diversion as a test case, two demonstrations were able to show the applicability of the system created. The first demonstration was able to characterize the flow characteristics of the physical system. The second demonstration was able to mimic and inhibit urea hydrolysis under realistic conditions. Ultimately, the use of this novel CPS approach was able to confirm the benefits of sensing and actuation in wastewater collection and treatment within buildings.

• In UV-free controls, urease activity in water and synthetic urine was similar, and higher than in real urine. • No urease activity was detected in water, synthetic urine and real urine after UV treatment. • Electrical energy demand to inactivate urease in real urine was 25-fold higher than synthetic urine. • Organic metabolites in real urine absorbed radiant flux and inhibited urease inactivation. In source-separating sanitation systems, inhibiting urease activity prevents enzymatic urea hydrolysis and volatilisation of ammonia when urine is concentrated by evaporation. This study tested UV-based photoinactivation as a novel alternative to existing methods of inactivating urease that require dosing urine with acid, base or oxidants. The enzymatic activity of jack bean (Canavalia ensiformis) urease in water, synthetic fresh urine and real fresh urine was investigated, with and without a 15 W low-pressure UV lamp that emitted 185 nm and 254 nm radiation. In UV-free controls, urea was hydrolysed at a rate of 3.2 × 10−3 mmol mg urease −1 min−1, 3.3 × 10−3 mmol mg urease −1 min−1 and 2.0 × 10−3 mmol mg urease −1 min−1 in water, synthetic urine and real urine, respectively. In the presence of UV, no urease activity was detected in any matrix. A UV irradiation time of 1.3 and 3.3 min was needed for inactivating urease in water and synthetic urine, respectively, whereas an irradiation time of 71 min was needed for inactivating urease in real urine. Overall, the electrical energy demand for photoinactivation of urease in real human urine was estimated to be 29.1 kWh m−3. Photolysis and photo-oxidation of amino acid residues at the active site of the enzyme were likely reasons for inactivation. Organic metabolites in real urine affected photoinactivation by (i) absorbing radiation between 190 nm and 400 nm, which reduced incident radiant flux; and (ii) scavenging hydroxyl radicals, which impeded oxidative damage to the enzyme. Overall, the findings demonstrate the feasibility of on-site treatment using a low-pressure UV lamp for inactivating urease in freshly excreted urine. [ABSTRACT FROM AUTHOR]

Within the international water sector, Durban's municipal practitioners have been widely celebrated, for innovations in retail pricing, new product development, creative service delivery and community participation. However, in a society as divided as South Africa, with a high degree of neoliberal public policy influence from international sources, the myriad social, economic and environmental contradictions have reached deep into Durban's water and sanitation politics. Distant parts of the city were neglected when it came to 'uneconomic' water and sewage pipe extension. Tokenistic supplies of water were given to poor people, but in a manner that left them with one-third lower consumption levels. In surveys, the no-flush toilets were overwhelmingly rejected by hundreds of thousands of recipients. It is in the destruction of older water and sanitation policies, and the creation of new ones for poor and working-class black Durban residents, that adds new meaning to critical analysis of 'roll back' and 'roll-in' neoliberalisms. [ABSTRACT FROM AUTHOR]

In the case of advanced stage gynecological disorders, most patients have a disturbance in the upper urinary tract. Most patients with uterine cervical carcinoma are already in stage 3B and require urine diversion. The purpose of this study is to find and determine the profile of gynecological disorders that require urine diversion, the type of urine diversion, and urine diverted output in patients with cervical carcinoma. This descriptive analytical retrospective study was conducted at Dr. Soetomo Hospital, Surabaya, Indonesia, between 2012 and 2015. The samples of this study were all patients with gynecological disorders who underwent retrograde DJ stent procedures, underwent ureterocutaneostomy and nephrostomy at the Integrated Central Surgery Building, Dr. Soetomo Hospital, Surabaya, for three years between 2012 and 2015. Data was collected based on the medical record number of patients with gynecological disorders who underwent urine diversion procedures and were recorded in the book on the operation schedule. We find that the most common cause of gynecological abnormalities in kidney obstruction is cervical carcinoma. There are three types of urine diversions used, namely DJ stent, percutaneous nefropyelostomy, and ureterocutaneostomy, with DJ as the most commonly performed. Urine diversion can improve creatinine without being influenced by the type of diversity. [ABSTRACT FROM AUTHOR]

Abstract Over four billion people are discharging untreated human excreta into the environment without any prior treatment, causing eutrophication and spreading disease. The most nutrient rich fraction is the urine. Urine can be collected separately and dehydrated in an alkaline bed producing a nutrient rich fertiliser. However, faecal cross-contamination during the collection risks to introduce pathogens to the urine. The objective of this hygiene assessment was to study the inactivation of five microorganisms (Ascaris suum, Enterococcus faecalis , bacteriophages MS2 and ΦX 174 and Salmonella spp) in alkaline dehydrated urine. Fresh human urine was dehydrated in wood ash at 42 °C until the pH decreased to ≤10.5, at which point the saturated ash was inoculated with faeces containing the microorganisms and left open to the air (mimicking stockpiling of the end product) at temperatures of 20 and 42 °C. The bacteria and bacteriophages were inactivated to below the detection limit (100 cfu ml−1 for bacteria; 10 pfu mL−1 for bacteriophages) within four days storage at 20 °C. A. suum inactivation data was fitted to a non-linear regression model, which estimated a required 325 days of storage at 20 °C and 9.2 days at 42 °C to reach a 3 log 10 reduction. However, the urine dehydration in itself achieved a concentration <1 A. suum per 4 g of dehydrated medium which fulfil the WHO guidelines for unrestricted use. [ABSTRACT FROM AUTHOR]

Implementation of water demand reduction strategies may impact downstream water quality. These practices and impacts are particularly important for arid west regions with frequent water supply shortages. Downstream water quality impacts on indoor conservation, source separation, and graywater and effluent reuse were quantified for an arid water system where receiving water stream is predominantly fed by snowmelt and experiences large fluctuations in flow. Estimates of indoor conservation indicate that, without wastewater treatment facility (WWTF) process modifications, conservation practices implemented during drought conditions to stretch a water supply will result in an increase in receiving water body nutrient concentrations (>25% increase in total nitrogen [TN] and total phosphorous [TP]). Graywater reuse practices for toilet flushing or irrigation have negligible impacts on WWTF performance and downstream water quality even with wide adoption of the practice (100% population adoption). Conversely, adoption of source separation is estimated to notably improve influent nutrient loading, which corresponded to an improvement in WWTF effluent loading. To meet potential stream standards, city-wide adoption of source separation would be necessary and there are likely more cost-effective and feasible opportunities for improvements at the WWTF. The downstream impact of WWTF effluent reuse is largely dependent on the receiving water body and seasonality of flows, but the practice is beneficial during mid-range flow and dry conditions when effluent reuse is most valuable as an additional supply (>25% decrease in TN and TP). However, water reuse does not provide a benefit to the WWTF under concentration-based permits. [ABSTRACT FROM AUTHOR]

In this study, we explored why urine recycling systems have failed to gain wide-scale expansion despite their high potential for food and fertilizer security. Additionally, we examined the future perception of urine recycling in Sweden and Switzerland, as these two countries are at the forefront of technological advancement. Along with identifying barriers, we also proposed pathways for overcoming those barriers and achieving the upscale. The analysis was conducted using the technological innovation (TIS) approach, which is technology-focused, i.e., revolves around emerging technologies. Additionally, the study provides a methodological contribution to the innovation systems research by employing the Delphi method in conjunction with urine recycling experts to enforce transparency and prevent bias in the analysis. For urine recycling to overcome its current challenges, actors must work collectively. There needs to be a combination of top-down and bottom-up efforts to achieve the upscaling pathways. Lobbying and knowledge provision are necessary to adjust the current regulatory framework in a manner that provides public and private incentives. For urine recycling to diffuse and break into the mainstream market, we must move beyond enthusiasts, innovators, and niche markets into the mass market (ordinary people); dedicated service providers can facilitate this process. Pilot projects have been found integral to urine recycling upscaling. Future work could conduct life cycle assessments on existing pilot projects to understand the environmental and economic performance of urine recycling systems when scaled up. [Display omitted] [ABSTRACT FROM AUTHOR]

• ΣOMP degradation of 99% in water and 55% in urine after 80 min UV-AOP (2100 J m-2). • Energy demand to degrade OMPs in urine was 10-fold higher than in Milli-Q water. • Organic compounds in urine compete with OMPs for UV light and scavenge free radicals. • Nitrogen content in urine is preserved during UV AOP and can be recovered afterwards. In household wastewater, a large proportion of organic micropollutants (OMPs) load is attributed to human urine. OMPs could pose a risk to human and environmental health when urine collected in source-separating sanitation systems is recycled as crop fertiliser. This study evaluated degradation of 75 OMPs in human urine treated by a UV-based advanced oxidation process. Fresh urine and water samples were spiked with a broad range of OMPs and fed into a photoreactor equipped with a UV lamp (185 and 254 nm) that generated free radicals in situ. Degradation rate constant and the energy required to degrade 90% of all the OMPs in both matrices were determined. At a UV dose of 2060 J m-2, average ΣOMP degradation of 99% (±4%) in water and 55% (±36%) in fresh urine was achieved. The energy demand for removal of OMPs in water was <1500 J m-2, but for removal of OMPs in urine at least 10-fold more energy was needed. A combination of photolysis and photo-oxidation can explain the degradation of OMPs during UV treatment. Organic substances (e.g. urea, creatinine) likely inhibited degradation of OMPs in urine by competitively absorbing UV-light and scavenging free radicals. There was no reduction in the nitrogen content of urine during treatment. In summary, UV treatment can reduce the load of OMPs to urine recycling sanitation systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Pyocystis, empyema cystis, vesical empyema are all terms that describe the purulent filled bladder that may develop in patients with defunctionalized bladders such as after supravesical urinary diversion without cystectomy or in patients with end-stage renal disease with anuria. It is a severe form of lower urinary tract infection. In addition to the local symptoms of suprapubic pain and malodorous discharge, the condition can be more serious with bacterial dissemination into the blood stream and ensuing sepsis and even mortality. The current review will discuss the pathogenesis, risk factors and management of this commonly forgotten complication of urinary diversion. [ABSTRACT FROM AUTHOR]

The toilets used most in informal urban settlements have detrimental consequences for the environment and human health due to the lack of proper collection and treatment of toilet waste. Concepts for safe, sustainable and affordable sanitation systems exist, but their feasibility and acceptance have to be investigated at an early stage of development, which is difficult due to the high costs of building working models. In this paper, we present an approach to estimate acceptance in a valid and representative form with only one working model, and apply it to test an innovative zero-emission toilet with recycling of wash water. Four basic principles were specified for investigation and nine hypotheses formulated to test the feasibility and acceptance of these principles: source separation of urine and feces with subsequent collection for resource recovery; provision of wash water in a separate cycle with on-site recovery through a membrane bioreactor; a convenient and attractive overall design; and a financially sustainable business plan. In Kampala (Uganda), in 2013, data was collected from 22 regular users, 308 one-time users and a representative sample of 1538 participants. Qualitative data was collected from the users, who evaluated their likes, perceived benefits, social norms and expected ease of use based on verbal and visual information. Most of the hypotheses were confirmed, indicating the feasibility and acceptance of the basic principles. Source separation and on-site water recovery were found to be feasible and accepted, provided users can be convinced that the emptying service and water recovery process work reliably. In the survey, the toilet was evaluated favorably and 51% of the participants agreed to be placed on a bogus waiting list. However, some design challenges were revealed, such as the size of the toilet, hiding feces from view and improving the separation of urine and water. [ABSTRACT FROM AUTHOR]

A 10-day-old Tennessee Walking Horse colt was hospitalised due to a pelvic urethral tear. After 2 unsuccessful attempts to repair the tear by primary closure, the colt underwent perineal urethroplasty and laparoscopic-assisted tube cystotomy which permitted complete urine diversion and allowed the urethral tear to heal completely. [ABSTRACT FROM AUTHOR]

Adopting urine-recycling technologies can support a transition to circular nutrient management systems. Although these technologies have been developed since the 1990s, their large-scale implementation remains limited. From a technological innovation system (TIS) perspective, "knowledge development and diffusion" is a critical function in the development phase. Yet, available methods in the literature to evaluate this function are not standardized. Hence, this study aims to fill this literature gap by developing a novel multi-criteria framework for evaluating knowledge functions. Several characteristics of emerging technologies are reflected in the criteria, including the rate of growth, novelty, diffusion, and relationship to incumbent systems. The knowledge base was measured by bibliometric analysis of publications obtained from comprehensive mapping. Results showed that the rate of publications and knowledge diffusion increased sharply in 2011–2021 compared to 1990–2010. However, the function still has insufficiency in some criteria. The lack of innovation in scientific research and the diversification of technologies were found to be impediments. The analysis also identified the lock-in of conventional technologies and centralized infrastructures in terms of publication dominance as another impediment. For the TIS to be legitimate and to grow, more pilot-scale implementations at a higher level are recommended to demonstrate that the technology works in practice. [ABSTRACT FROM AUTHOR]

This paper will explain how a framework derived from systems thinking, including soft systems methodology and the use of action research as a methodology, shaped a research project addressing an area of application (sustainable sanitation). The research used F (intellectual framework) M (methodology for using F) to address A (area of application) for understanding rational intervention in human affairs proposed by Peter Checkland in the 1980s. This Australia-first research project was conducted by a multidisciplinary team of collaborators from academia, industry and government that included researchers, practitioners and students. It explored the use of innovative urine-diverting toilets in an institutional setting. The paper is focussed on the initial stages of the project--the project design and early investigative phase, and demonstrates how systems thinking and a transdisciplinary research approach were used to structure a complex problem related to sustainability, a problem that infringed on social and cultural issues. [ABSTRACT FROM AUTHOR]

The quality of life in patients with urinary incontinence or irreparable urethral stricturing can be improved by diversion with construction of catheterizable urinary stomas. We report our experience with three patients who required urinary diversion and underwent the Mitrafanoff procedure. The cases involved an eight year old with myelomeningocele, paraplegia and urinary incontinence, a 32 year old male with irreparable traumatic urethral stricture and an eighteen year old paraplegic man who developed urethral stricture secondary to prolonged catheterization for urine retention. Three years after their surgeries, they are continent with normal renal function.