Uhl, Mathias
Refine
Year of publication
Document Type
- Part of a Book (62)
- Lecture (44)
- Article (42)
- Book (5)
- Article in Conference Proceedings (4)
- Report (1)
Language
- German (95)
- English (52)
- Multiple languages (11)
Is part of the Bibliography
- no (158)
Keywords
- Entwässerungssysteme (1)
- Evapotranspiration (1)
- R (1)
- Regenwasserbewirtschaftung (1)
- RoGeR (1)
- SWMM (1)
- SWMM-UrbanEVA (1)
- Stormwater Quality (1)
- Vegetation (1)
- Verdunstung (1)
Institute
In Germany, the current sectoral urban planning often leads to inefficient use of resources, partly because municipalities lack integrated planning instruments and argumentation strength toward politics, investors, or citizens. The paper develops the ResourcePlan as (i) legal and (ii) a planning instrument to support the efficient use of resources in urban neighborhoods. The integrative, multi-methodological approach addresses the use of natural resources in the building and infrastructural sectors of (i) water (storm- and wastewater) management, (ii) construction and maintenance of buildings and infrastructure, (iii) urban energy system planning, and (iv) land-use planning. First, the development as legal instrument is carried out, providing (i) premises for integrating resource protection at all legal levels and (ii) options for implementing the ResourcePlan within German municipal structures. Second, the evaluation framework for resource efficiency of the urban neighborhoods is set up for usage as a planning instrument. The framework provides a two-stage process that runs through the phases of setting up and implementing the ResourcePlan. (Eco)system services are evaluated as well as life cycle assessment and economic aspects. As a legal instrument, the ResourcePlan integrates resource protection into municipal planning and decision-making processes. The multi-methodological evaluation framework helps to assess inter-disciplinary resource efficiency, supports the spatial identification of synergies and conflicting goals, and contributes to transparent, resource-optimized planning decisions.
The water balance of urban areas differs considerably from the landscape water balance. Increased surface runoff, reduced groundwater recharge and evaporation change the hydrological regime, the morphology and ecology of water bodies close to the cities, the groundwater in the urban area and the urban climate. Today's urban drainage systems are designed to prevent, reduce, drain, seep away, evaporate or discharge precipitation into nearby surface waters with considerable delays. In doing so, it follows the principles of the German Water Resources Act (WHG) and the objectives of the relevant technical regulations DWA-A 102 to keep changes in the natural water balance by settlement activities as low as ecologically, technically and economically acceptable. A reference for the "natural" water balance has to be defined as a planning objective in order to quantify the hydrological changes in settlements. As a suitable reference, we propose to use the water balance of the landscape of the associated ecoregion with today's cultural land use without urban developments. This approach is more suitable to define local conditions than the water balance of the enclosed catchment. The presented calculation approach to define reference values of the water balance, uses soil and geological properties, precipitation and climate data and can be implemented and applied uniformly throughout Germany. The water balances in this study are simulated with the water balance model RoGeR. In this study, the developed approach is applied for five locations in Germany.
Im Rahmen einer nachhaltigen Stadtentwicklung wird der Vegetation die
Funktion der Beschattung und Verdunstung zugesprochen. Der Stadthydrologie fehlte hierfür bislang ein geeignetes Simulationsmodell. Der entwickelte Modellbaustein SWMM-UrbanEVA erlaubt die standortgerechte Simulation der Verdunstung von Vegetation im urbanen Raum. Für Freiflächen erfolgt die Prozessmodellierung des Energie- und Wasserhaushaltes des Systems Boden-Pflanze-Atmosphäre. Mit meteorologischen und vegetationskundlichen Kenndaten wird eine raum-zeitlich differenzierte Berechnung ermöglicht.
Die Verdunstung als Teil des urbanen Wasserhaushalts sollte aus wasserwirtschaftlicher und energetischer Sicht im Rahmen von Planungsprozessen zielgerichtet beeinflusst werden. Lösungs-strategien können nur in einem iterativen und interdisziplinä-ren Prozess entwickelt werden. So ergeben sich zahlreiche pla-nerische Optionen blau-grüner Infrastruktur, die anhand des Oxford-Quartiers in Münster exemplarisch dargestellt werden. Die erfolgreiche Umsetzung solcher ganzheitlichen Planungen erfordert interdisziplinäre Zusammenarbeit über bisherige kom-munale Organisations- und Arbeitsstrukturen hinweg. Je nach Planungsphase unterstützen dabei unterschiedlich differenzier-te Planungswerkzeuge die Entscheidungsfindung (zum Beispiel WABILA, SWMM-UrbanEVA).
The in-situ performance of large decentralised stormwater treatment systems is investigated by means of continuous turbidity measurements. Turbidity measurements are used as a surrogate to continuously estimate Total Suspended Solid (TSS) concentrations. TSS event loads are calculated at the inlet and outlet of two stormwater treatment systems, which both are installed at the outlet of catchments with high pollution potential. The event-specific performance is defined as ratio between TSS loads of inflow and outflow. Based on measurement data obtained, the overall TSS load retention efficiency is about 32 %.
Stormwater quality models are usually calibrated using observed pollutographs. As current models still rely on simplified model concepts for pollutant accumulation and wash-off, calibration results for continuous pollutant concentrations are highly uncertain. In this paper, we introduce an innovative calibration approach based on total suspended solids (TSS) event load distribution. The approach is applied on stormwater quality models for a flat roof and a parking lot for which reliable distributions are available. Exponential functions are employed for both TSS buildup and wash-off. Model parameters are calibrated by means of an evolutionary algorithm to minimize the distance between a parameterized lognormal distribution function and the cumulated distribution of simulated TSS event loads. Since TSS event load characteristics are probabilistically considered, the approach especially respects the stochasticity of TSS buildup and wash-off and, therefore, improves conventional stormwater quality calibration concepts. The results show that both experimental models were calibrated with high goodness-of-fit (Kolmogorov–Smirnov test statistic: 0.05). However, it is shown that events with high TSS event loads (>0.8 percentile) are generally underestimated. While this leads to a relative deviation of −28% of total TSS loads for the parking lot, the error is compensated for the flat roof (+5%). Calibrated model parameters generally tend to generate wash-off proportional to runoff, which is indicated by mass-volume curves. The approach itself is, in general, applicable and creates a new opportunity to calibrate stormwater quality models especially when calibration data is limited.
Results from a long-term stormwater quality monitoring program were used to derive total suspended solids (TSS) event load distributions at four small urban environments (flat roof, parking lot, residential catchment, high traffic street). Theoretical distribution functions were fitted to the empirical distribution functions obtained. Parameters of the theoretical distribution functions were optimized with respect to a likelihood function to get both optimized parameters and standard errors. Kolmogorov-Smirnov and Anderson-Darling test statistics were applied to assess the goodness-of-fit between empirical and theoretical distribution. The lognormal distribution function was found to be most expressive to approximate empirical TSS event load distributions at all sites. However, the goodness-of-fit of the statistical model strongly depends on the number of events available. Based on the results of a Monte-Carlo-based resampling strategy, around 40 events should be considered.
Der Behandlung von Niederschlagsabflüssen aus Trennsystemen kommt zur Zielerreichung eines wirksamen Gewässerschutzes eine wesentliche Rolle zu. Konventionelle, zentrale Anlagen behandeln den Abfluss vor der Einleitung in das Gewässer. Zunehmend an Bedeutung gewonnen haben dezentrale Anlagen, die den Abfluss am Entstehungsort behandeln. Unterschiedlich belastete Oberflächenabflüsse können somit den wasserrechtlichen Anforderungen entsprechend gezielt behandelt werden. Voraussetzung zur Anwendung ist der Nachweis der vergleichbaren Reinigungsleistung zu zentralen Anlagen. In-situ Gütemessungen der Zu- und Ablauffrachten einer Behandlungsanlage ermöglichen eine datenbasierte Bewertung der Anlagenwirksamkeit.
The stormwater management model SWMM of the US EPA is widely used to analyse, design or optimise urban drainage systems. To perform advanced analysis and visualisations of model data this technical note introduces the R package swmmr. It contains functions to read and write SWMM files, initiate simulations from the R console and to convert SWMM model files to and from GIS data. Additionally, model data can be transformed to produce high quality visualisations. In accordance with SWMM’s open source policy the package can be obtained through github.com or the Comprehensive R Archive Network (CRAN).
