Quantifying debris-flow hazard and risk based on fan sector

We show how a quantitative estimate of debris-flow hazard and risk can be derived simply from the position of infrastructure on the fan relative to the fan apex and the most likely flow path (e.g., active channel). Fan sectors and the spatial probability of impact in each sector are based on a fan-normalized heat map of debris-flow impacts derived from 146 mapped impact areas across 30 fans in southwestern British Columbia, Canada. As a proof-of-concept, we provide an example for annual life loss risk to an individual who occupies a home in various sectors of a debris-flow fan. The results are comparable to broad findings from quantitative risk assessments completed at 10 fans in British Columbia and Alberta, Canada with similar characteristics. The method presented here is a way to obtain a high-level quantitative risk estimate prior to a detailed site-specific assessment

A multi-year record of topographic changes on debris-flow fans in south-western British Columbia, Canada

Repeat observations of four debris-flow fans in south-western British Columbia, Canada, were made using a UAV-lidar system. Detailed measurements of deposit thicknesses and volumes have been generated from the data. We present channel measurements and characteristics for one of the sites to demonstrate the utility of the repeat lidar scanning technique to provide insights into where avulsions occur during debris flows. Through continued monitoring, we plan to obtain greater detail on a wider variety of events and the characteristics of avulsion locations

Outcomes of delivering a fertility preservation service for women with cancer over a 12-year period at a UK assisted conception unit.

This service evaluation aimed to appraise the delivery of a fertility preservation service for women with cancer which was established in 2005 as part of an Assisted Conception Unit. First, the ACU-database was interrogated between 08/2005 and 01/2017; revealing 174 women received referrals over the 12-year period with a steady referral increase each year. Demographic analyses revealed factors, such as being partnered, to be strong indicators of whether women would seek FP or not. To improve service provision, women who had consented to be contacted for audit, administrative and research purposes, received questionnaires to ascertain their perspectives on the FP decision-making process, their outcomes and ACU after-care. The majority perceived their experience as excellent due to the care they received from ACU staff, speed and efficiency in service delivery. The increasing number of referrals since 2005 is reassuring. However, this audit also highlighted shortcomings of the service, such as limited awareness of the fertility counselling service and lack of after-care. IMPACT STATEMENT What is already known on this subject? There has been an increase in women diagnosed with cancer undergoing fertility preservation (FP) before starting potential gonadotoxic treatment. Offering FP to these women is essential as the ability to have future children is often perceived as equally as important as survivorship, and a source of hope for the future. What do the results of this study add? This study presents a service evaluation, across a 12-year period, of delivering FP services to women with cancer in one UK Assisted Conception Unit (ACU). Women's experiences of the service were evaluated to enhance service delivery and make recommendations for clinical practice. What are the implications of these findings for clinical practice and/or future research? The current service evaluation demonstrated increased rates of FP referral over a 12-year period for women with cancer. While this increasing number is reassuring and reflecting increased awareness among professionals and patients; shortcomings in the care pathway were also found: women reported limited opportunity to see fertility counsellors and desired better after care. This information may also be of benefit to other ACUs seeking to enhance and improve service provision in the care of women with cancer, contemplating fertility preservation

Geomorphic mapping and UAV lidar of debris flow fans in southwestern British Columbia, Canada

The data consists of geomorphic fan mapping completed at 29 debris flow fans in southwestern British Columbia, Canada, and uncrewed aerial vehicle (UAV) lidar at three of these fans. This dataset was used to study the spatial record of debris-flow impacts on fans for hazard and risk assessments. The fan mapping geodatabase contains fan boundaries, fan apexes, watershed boundaries, impact areas (any area below the fan apex that has been overrun by a debris flow since the last observation record), and flow paths (the channel or main flow path associated with an impact area). Fan mapping was completed using orthorectified airphotos, satellite imagery, topographic base maps, lidar data, orthophotos, and field observations. UAV lidar was collected at three of the 29 fans in the fall of 2019 for the purposes of geomorphic mapping and change detection analysis. One of the fans is located near Mt. Currie (Currie D) and two are located near Lillooet (Fountain N, Fountain S). Lidar for Currie D was flown on October 1 and 2, 2019, and has an average point density of 6.7 points per square meter, an average point spacing of 0.38 meters, and covers and area of 0.5 square kilometers. Lidar for Fountain N was flown on October 23, 2019, and has an average point density of 8.1 points per square meter, an average point spacing of 0.35 meters, and covers and area of 0.95 square kilometers. Lidar for Fountain S was flown on September 18-19, 2019, and has an average point density of 8.1 points per square meter, an average point spacing of 0.35 meters, and covers and area of 0.44 square kilometers. The lidar is provided as classified point clouds (LAS files), NAD83 / UTM zone 10N

A multi-year record of topographic changes on debris-flow fans in south-western British Columbia, Canada

Repeat observations of four debris-flow fans in south-western British Columbia, Canada, were made using a UAV-lidar system. Detailed measurements of deposit thicknesses and volumes have been generated from the data. We present channel measurements and characteristics for one of the sites to demonstrate the utility of the repeat lidar scanning technique to provide insights into where avulsions occur during debris flows. Through continued monitoring, we plan to obtain greater detail on a wider variety of events and the characteristics of avulsion locations

Outcomes of delivering a fertility preservation service for women with cancer over a 12-year period at a UK assisted conception unit

This service evaluation aimed to appraise the delivery of a fertility preservation service for women with cancer which was established in 2005 as part of an Assisted Conception Unit. First, the ACU-database was interrogated between 08/2005 and 01/2017; revealing 174 women received referrals over the 12-year period with a steady referral increase each year. Demographic analyses revealed factors, such as being partnered, to be strong indicators of whether women would seek FP or not. To improve service provision, women who had consented to be contacted for audit, administrative and research purposes, received questionnaires to ascertain their perspectives on the FP decision-making process, their outcomes and ACU after-care. The majority perceived their experience as excellent due to the care they received from ACU staff, speed and efficiency in service delivery. The increasing number of referrals since 2005 is reassuring. However, this audit also highlighted shortcomings of the service, such as limited awareness of the fertility counselling service and lack of after-care.IMPACT STATEMENT What is already known on this subject? There has been an increase in women diagnosed with cancer undergoing fertility preservation (FP) before starting potential gonadotoxic treatment. Offering FP to these women is essential as the ability to have future children is often perceived as equally as important as survivorship, and a source of hope for the future. What do the results of this study add? This study presents a service evaluation, across a 12-year period, of delivering FP services to women with cancer in one UK Assisted Conception Unit (ACU). Women’s experiences of the service were evaluated to enhance service delivery and make recommendations for clinical practice. What are the implications of these findings for clinical practice and/or future research? The current service evaluation demonstrated increased rates of FP referral over a 12-year period for women with cancer. While this increasing number is reassuring and reflecting increased awareness among professionals and patients; shortcomings in the care pathway were also found: women reported limited opportunity to see fertility counsellors and desired better after care. This information may also be of benefit to other ACUs seeking to enhance and improve service provision in the care of women with cancer, contemplating fertility preservation

Variable hydrograph inputs for a numerical debris-flow runout model

Debris flows affect people and infrastructure around the world, and as a result, many numerical models and modelling approaches have been developed to simulate their impacts. Observations from instrumented debris-flow channels show that variability in inflow depth, velocity and discharge in real debris flows is much higher than what is typically used in numerical simulations. However, the effect of this natural variability on numerical model outputs is not well known. In this study, we examine the effects of using complex inflow time series within a single-phase runout model utilizing a Voellmy flow-resistance model. The interactions between model topography and flow-resistance were studied first using a simple triangular hydrograph, which showed simulated discharges change because of local slopes and Voellmy parameters. Next, more complex inflows were tested using time series based on 24 real debris-flow hydrographs initiated from three locations. We described a simple method to scale inflow hydrographs by defining a target event volume and maximum allowable peak discharge. The results showed a large variation in simulated flow depths and velocities arising from the variable inflow. The effects of variable inflow conditions were demonstrated in simulations of two case histories of real debris flows, where the variation in inflow leads to significant variations in the simulation outputs. The real debris-flow hydrographs were used to provide an indication of the range of impacts that may result from the natural variability in inflow conditions. These results demonstrate variation in inflow conditions can lead to reasonable estimates of the potential variation in impacts

Variable hydrograph inputs for a numerical debris-flow runout model

Debris flows affect people and infrastructure around the world, and as a result, many numerical models and modelling approaches have been developed to simulate their impacts. Observations from instrumented debris-flow channels show that variability in inflow depth, velocity, and discharge in real debris flows is much higher than what is typically used in numerical simulations. However, the effect of this natural variability on numerical model outputs is not well known. In this study, we examine the effects of using complex inflow time series within a single-phase runout model utilizing a Voellmy flow-resistance model. The interactions between model topography and flow resistance were studied first using a simple triangular hydrograph, which showed that simulated discharges change because of local slopes and Voellmy parameters. Next, more complex inflows were tested using time series based on 24 real debris-flow hydrographs initiated from three locations. We described a simple method to scale inflow hydrographs by defining a target event volume and maximum allowable peak discharge. The results showed a large variation in simulated flow depths and velocities arising from the variable inflow. The effects of variable-inflow conditions were demonstrated in simulations of two case histories of real debris flows, where the variation in inflow leads to significant variations in the simulation outputs. The real debris-flow hydrographs were used to provide an indication of the range of impacts that may result from the natural variability in inflow conditions. These results demonstrate that variation in inflow conditions can lead to reasonable estimates of the potential variation in impacts.ISSN:1561-8633ISSN:1684-998