Subsurface tile drainage is a common management practice implemented by farmers throughout the Midwest in fields that have poorly drained soils. Tile drainage has several benefits including increased productivity, reduced erosion, and increased trafficability. However, relatively little is known about the long-term change of soil properties that may occur as a result of subsurface drainage. Careful monitoring of tile drains at the long-term experimental site at the Southeast Purdue Agricultural Center led to the observation of faster drain flow than in the past, with hydrographs of the flow showing flashier peaks, suggesting that more preferential flow paths have developed over time. The overall goal of this study was to characterize possible evolution of physical and hydraulic properties of this silt loam soil after 35 years of subsurface drainage. Bulk density and water retention were measured in May of 2018 at 0-5 cm, 5-15 cm, and 15-30 cm in all plots and again in July of 2019 in the 5 m and 40 m spacings at four different horizons down to depths of approximately 100 cm, rather than set depth increments. Bulk density results from both sets of sampling show the 5 m spacing to have a significantly lower bulk density than the 40 m spacing in the top 30 cm of soil, although the difference was small. Differences in water retention among treatments were too small to be physically meaningful. Saturated hydraulic conductivity results measured by three different methods were highly variable and no differences were detected. In soils with naturally weak structure, low organic matter, and low clay content, like the soil in this study, the processes responsible for soil aggregation, structure stabilization, and lowering bulk density are inherently slow and may require longer than 35 years of subsurface drainage to produce significant changes in the physical properties measured.

Der Abbau der Uranerzlagerstätte Schlema-Alberoda von über Tage bis in eine Teufe von 2000 m und die anschließende Flutung führten zu Einwirkungen auf die Tagesoberfläche u.a. in Form von Senkungen, Hebungen, Horizontalverschiebungen und seismischen Entspannungen. Im Grubenteil Oberschlema entstand durch intensiven Abzug des Eigenversatzes aus dem Firstenstoßbau ein Bruchkörper (sog. Deformationsgebiet), der einen ca. 3,3 km² großen Senkungstrog mit Senkungen bis 6 m, mehrere hundert Meter lange Erdrisse und eine ca. 30 Jahre anhaltende Nachsenkungsphase mit Senkungen bis 3 cm/a verursachte (abbaubedingte Bodenbewegungen). Infolge der abbaubedingten Bodenbewegungen, der Vielzahl von tagesnahen Grubenbauen und daraus entstandener Tagesbrüche, musste der Kurort Oberschlema fast vollständig abgebrochen werden. Das ca. 25 ha große, als Deformationsgebiet bezeichnete Gelände wurde eingezäunt. Nach 1994 entstand in diesem Gebiet ein Kurpark. Mit der Stilllegung der Grube Schlema-Alberoda begann die Flutung. Ab 1998 wurde auch der Bruchkörper geflutet. Entsprechend der bisher beobachteten Bodenbewegungen reagiert der Bruchkörper und das relativ standfeste umgebende Grubengebäude unterschiedlich auf die Flutung. Über dem Bruchkörper wurden Schieflagen um 4 mm/m, Verschiebungen über 15 cm, Zerrungen bis 6 mm/m und Pressungen bis zu 5 mm/m ermittelt. Über dem Grubenteil Niederschlema-Alberoda konnten mit den bis Oktober 2016 durchgeführten Nivellements flutungsbedingte großflächige Hebungen bis 12 cm nachgewiesen werden. Ursache der Hebungen sind Dehnungen des durchbauten Gebirgskörpers bis in eine Teufe von ca. 1000 m. In dem Beitrag wird das für die Beobachtung und Interpretation der geomechanischen Auswirkungen der Flutung der Grube durchzuführende Monitoring sowie einige Ergebnisse vorgestellt.

Experimental design can be vital when experiments are resource-exhaustive and time-consuming. In this work, we carry out experimental design in the Bayesian framework. To measure the amount of information that can be extracted from the data in an experiment, we use the expected information gain as the utility function, which specifically is the expected logarithmic ratio between the posterior and prior distributions. Optimizing this utility function enables us to design experiments that yield the most informative data about the model parameters. One of the major difficulties in evaluating the expected information gain is that it naturally involves nested integration over a possibly high dimensional domain. We use the Multilevel Monte Carlo (MLMC) method to accelerate the computation of the nested high dimensional integral. The advantages are twofold. First, MLMC can significantly reduce the cost of the nested integral for a given tolerance, by using an optimal sample distribution among different sample averages of the inner integrals. Second, the MLMC method imposes fewer assumptions, such as the asymptotic concentration of posterior measures, required for instance by the Laplace approximation (LA). We test the MLMC method using two numerical examples. The first example is the design of sensor deployment for a Darcy flow problem governed by a one-dimensional Poisson equation. We place the sensors in the locations where the pressure is measured, and we model the conductivity field as a piecewise constant random vector with two parameters. The second one is chemical Enhanced Oil Recovery (EOR) core flooding experiment assuming homogeneous permeability. We measure the cumulative oil recovery, from a horizontal core flooded by water, surfactant and polymer, for different injection rates. The model parameters consist of the endpoint relative permeabilities, the residual saturations and the relative permeability exponents for the three phases: water, oil and microemulsions. We also compare the performance of the MLMC to the LA and the direct Double Loop Monte Carlo (DLMC). In fact, we show that, in the case of the aforementioned examples, MLMC combined with LA turns to be the best method in terms of computational cost.

Climate changes are predicted to increase precipitation intensities and occurrence of extreme rainfall events in the near future. Scandinavia has been identified as one of the most sensitive regions in Europe to such changes; therefore, an increase in the risk for flooding, landslides and soil erosion is to be expected also in Sweden. An increase in the occurrence of extreme weather events will impose greater strain on the built environment and major transport infrastructures such as roads and railways. This research aimed to identify the risk of flooding at the road-stream intersections, crucial locations where water and debris can accumulate and cause failures of the existing drainage facilities. Two regions in southwest of Sweden affected by an extreme rainfall event in August 2014, were used for calibrating and testing a statistical flood prediction model. A set of Physical Catchment Descriptors (PCDs) including road and catchment characteristics was identified for the modelling. Moreover, a GIS-based topographic Index of Sediment Connectivity (IC) was used as PCD. The novelty of this study relies on the adaptation of IC for describing sediment connectivity in lowland areas taking into account contribution of soil type, land use and different patterns of precipitation during the event. A weighting factor for IC was calculated by estimating runoff calculated with SCS Curve Number method, assuming a constant value of precipitation for a given time period, corresponding to the critical event. The Digital Elevation Model of the study site was reconditioned at the drainage facilities locations to consider the real flow path in the analysis. These modifications led to highlight the role of rainfall patterns and surface runoff for modelling sediment delivery in lowland areas. Moreover, it was observed that integrating IC into the statistic prediction model increased its accuracy and performance. The calibrated model was then validated in another area, located in the central part of Sweden, affected by severe rainfall event in August 2004, in order to verify its robustness even in ungauged catchments.

Flooding is already an issue that occurs from time to time. With climate changes the frequency of floods that occur due to heavy rainfall will most likely increase. Sweden is no exception and cities in Sweden have been victims of heavy rainfall events and floods. This leads to a need of climate change adaptation in municipalities. The municipalities in Sweden have monopoly on planning and are therefore utterly responsible to plan and adapt to climate changes. Planning can both be to prevent flooding from occurring but also to adapt the municipality to floods, in other words, when a flooding occur the consequences and damage will be minimized. The method used in this research was literature review. The research studied municipalities responsibilities connected to the flooding issue but also advice and recommendations from other authorities, as well as what measures municipalities can take to avoid flooding or minimize the consequences. The research also includes a short case study of Umeå municipality to study their work on the issue. The results mainly show that it is important to plan for flooding early in the planning process. However, the continuously work in every stage in the planning process to adapt to flooding or minimize the consequences of them is important. This research showed that it is a lack of adaptation for flooding in Umeå municipality.

The main aim of this Master Thesis is the design of several hydraulic structures to decrease as much as possible the huge flooding caused by the Escartana gully which drains its water towards the city of Albacete (Spain) and its surrounding areas, affecting to their inhabitants; and causing huge material damages in residential and industrial areas, and loss of crops in nearby farmland. Some alternatives such as embankment dams with or without drainage systems inside the dam body and a roller-compacted concrete (RCC) dam have been proposed to be built, being necessary to carry out a multicriteria analysis in order to decide which alternative has the best fit according to the analyzed features of the region. The alternative chosen to be developed was the RCC dam for the advantages of this typology, currently in development and implantation in some countries like Spain. For this reason, a RCC dam is planned to be built some kilometers upstream of these areas, with the objective of controlling the future floods coming from this watershed by decreasing its peak flow. In order to increase the beneficial effects of the construction of the dam, a channel downstream is also designed to drain the discharged overflows by the drainage systems of the dam towards a natural endorheic area, the Salobral Lagoon (currently dried-up), located 13 kilometers downstream of the dam’s location. This lagoon is connected hydraulically to the drainage network of Albacete by means of the Salobral channel and due to its huge storage capacity, it allows to reduce substantially the peak flows over the Salobral channel avoiding the dangerous flooding and potential damages caused by them. As a result of the projected hydraulic structures, Albacete and its surrounding areas would increase substantially their protection against the floods coming from the Escartana watershed.

How can flooding and circular principles in architecture become catalysts for rural revitalisation and resilience? A project that engages with the interaction between humans, nature and non-human actors. Exploring how landscape, architecture and ecology can become providers of catalytic strategies that can embrace uncertainty, multifunctionality and change over time. "Sense The Marsh" focuses on creating an engaging learning landscape that builds on the local unique site conditions and deals with flooding as an instrument to create experiences and raise awareness.

Lagos State in Nigeria is faced with the massive problem of waste from plastic bags which causes the yearly flooding displacing thousands of residents and causes diseases like malaria. Plastic bags which became popular because of their versatility, affordability and durability have now become a major source of environmental degradation requiring the use of more environmentally friendly alternatives like Jute, woolen bags, and biodegradable types of plastic. The Nigerian legislature proposed a plastic bag prohibition bill to reduce the manufacture and use of plastic bags with fines and time behind bars which is Nigeria’s first attempt at managing the menace of single-use plastic bags. The goal of this study is to determine reasons for the continued use of plastic bags to contribute to better management of plastic bags waste. It further investigates the available alternatives and willingness of the residents of Lagos to embrace some alternatives to plastic bags. Anonymous online surveys were distributed across social media platforms and interviews involving shop owners described as “givers” who are off social media in this study was carried out. Responses from both quantitative and qualitative sources have been analyzed using the Nvivo software and connection circles have been developed to describe feedbacks within the system. Results showed that the lack of alternatives and convenience are the biggest reasons for the continued use of plastic bags in Lagos, Nigeria. The results further show that the proposed bill has not made provision of alternatives to plastic bags and incentives for manufacturers of plastic bags revealing poor public participation in policy-making of this nature. Overall, respondents have indicated a willingness to embrace alternatives to plastic bags and have mentioned that the situation is worsened by poor waste management in the state. Recommendations included more extensive research into the use of plastic bags with a bigger sample size with both online and offline platforms. This could encourage effective public participation in policy-making important for creating useful nudges in behavioural change in the shift from plastic bags.

<p>Disturbance regimes like freezing and thawing (FT) can have potentially significant impacts on nutrient release from soil and are predicted to increase with climate change. This is particularly important in biogeochemical hotspots like floodplains that can both remove and release nutrients to surface waters during flooding. Connection between the river and floodplain can improve water quality by reducing nutrient loads through microbial processes and sedimentation. However, conditions during flooding can also lead to phosphorus (P) release from pools that are not normally bioavailable. Disturbance events like FT can also lead to changes in bioavailable P due to microbial cell lysis. This study investigates differences in P chemistry and flux during flooding from intact soil cores that have undergone a FT cycle compared to soils that have not undergone freezing. Floodplain soils were collected from four sites along the Wabash and Tippecanoe Rivers in Indiana. We hypothesized that (i) the primary pools of P within the soil would change with freezing (ii) and flooding; (iii) frozen treatment cores would release more P during flood incubations than unfrozen control cores; and (iv) processes controlling P release during flood incubations would change after FT due to changes in the primary pools of P in the soil cores. </p> <p> </p> <p>On average, soil cores that underwent FT released greater amounts of P than unfrozen cores over the course of the 3-week experimental flood incubation. Phosphorus release in both unfrozen control and FT treatment cores during flooding was explained in part by soil extractable Al and Fe and redox status; however, P release was influenced by soil Ca-P in the FT cores to a greater extent than unfrozen cores. Phosphorus release in FT cores occurred faster than in control cores with overlying water concentrations peaking 2 weeks after onset of flooding, followed by lower concentrations at 3 weeks. Whereas control cores had some release and uptake early on but then released P throughout the 3-week incubation—supporting the hypothesis that drivers of P release were different after FT. Interactive effects of FT and flooding suggest that concentration gradients between soil pore water and overlying surface water could have enhanced dissolution of the Ca-P pool, highlighting the importance of floodwater chemistry to P dynamics following FT. This study provides an important link between observed winter floodplain P loss and potential drivers of release and retention, which is critical to informing floodplain restoration design and management through all seasons.</p>

ABSTRACT: Umeå has had its troubles with flooding over the years. This study aims to describe and analyze flooding and stormwater management in the municipality of Umeå in Sweden. How the municipality is handling the responsibility to minimize the risk of flooding in problem areas and how they are planning to prevent flooding with stormwater management methods in both old and new districts of the city. With information gathered from the municipality itself and from other reports and websites of worth, I have compared the results I’ve gotten partly from my own field visits in the areas that are being planned for changes and partly from other reports. With that said, this study is a descriptive study with a focus on comparisons.