Die EG‐Wasserrahmenrichtlinie: Ausweisung und Bewertung künstlicher und erheblich veränderter Gewässer

Designation and Assessment of Artificial and Heavily Modified Water Bodies under the EC Water Framework Directive The EC Water Framework Directive allows the Member States to designate artificial and heavily modified water bodies under specific conditions. For those water bodies the ecological assessment and the resulting programmes of measures will be based on the “maximum ecological potential” as reference conditions and not on the “high ecological status”, which has to be used for natural water bodies. Such designation is possible only, if the hydromorphology of the water bodies concerned has been substantially changed in character to maintain specified uses. The criteria for the designation are fulfilled, if restoration measures needed to meet the high ecological status would have significant adverse effects on the uses and if no other better environmental options would exist to maintain the specified uses. In late 1999 the EC‐Working Group on Heavily Modified Water Bodies (HMWB) has been established to develop criteria for the designation of artificial and heavily modified water bodies as well as for the determination of the maximum ecological potential. The working group has produced the guidance document “Identification and Designation of Artificial and Heavily Modified Water Bodies” in November 2002, which has been agreed by the European Water Directors on 21 November 2002 in Copenhagen. The guidance document is focusing on two time borders, the provisional identification of heavily modified water bodies until 2004 and the legally binding designation as artificial and heavily modified in the first river basin management plan in 2009 at the latest. The guidance document considered the main findings of 34 case studies for rivers, lakes, transitional and coastal waters carried out in 11 European countries. The results of the case studies as well as a summarizing synthesis were used as a fundamental basis to produce the guidance document. The practical examples given by the case studies were compiled as a toolbox which supplements the guidance for the purpose of its better application.     

Zum Einfluß des pH-Wertes und des Calciumgehaltes auf Metall-Fulvinsäure-Bindungen — Inversvoltammetrische und chemometrische Untersuchungen

The Influence of pH and Calcium Concentration on Metal-Fulvic Acid Bonds – Stripping Voltammetric and Chemometric Investigations. Electrochemically available metal concentrations of Cd, Cu and Zn were analyzed in dependence of different concentrations of calcium, fulvic acids and pH by Differential Pulse Anodic Stripping Voltammetry (DPASV). A statistical experimental design was the base to minimize the number of experiments and to include the multifarious interactions between the independent variables (Ca concentration, concentration of fulvic acids and the pH value) and otherwise the electrochemically available metal concentrations of Cd, Cu and Zn. At first analysis of experimental data was carried out by multiple linear regression. The main influence on available metal concentrations is the pH value especially for Cu. The Ca ion influence has not competitive effect and is only significant for Cd and Cu. It has an effect on the metal-fulvic acid-bonds. Two factor interactions exist for pH/fulvic acids and for Ca/fulvic acids too. The partial least squares regression (PLS) model was used to include the interactions between the metals Cd, Cu and Zn. For proving these two models the three parameters pH, Ca and fulvic acid were varied within the calibration range of the models and predicted values were compared with the experimental values. The approach with the PLS model is better than the approach with the multiple linear regression (normally used mathematical method of analysis of a factorial plan) with a relative error of 9.7% for modelling of Cd, 6.0% for Zn and 58% for Cu in relation to multiple linear regression with errors of 12% for Cd, 8.6% for Zn and 65% for Cu. The PLS modelling is a suited tool for modelling chemical interactions also in simulated natural matrices.     

Vorkommen natürlicher und synthetischer östrogener Steroide in Wässern des süd‐ und mitteldeutschen Raumes

Distribution of Natural and Synthetic Estrogenic Steroid Hormones in Water Samples from Southern and Middle Germany Natural and synthetic hormones can reach surface waters via domestic sewage effluents. For drinking water production, bank filtration of river waters is a common procedure and hormone contaminations can potentially reach groundwater levels and drinking water sources. In order to analyse steroid hormones in the different aquatic compartments (raw sewage and effluent, surface water, groundwater, raw and drinking water) of South and Middle Germany, a sensitive analytical method was developed and employed to detect the natural steroid hormones estradiol (E2) and estrone and the synthetic estrogen ethinylestradiol (EE2). Samples which were taken in two subsequent series were subjected to clean‐up and enrichment procedure and subsequently analysed by HPLC‐MS. The limit of quantitation for the method was determined to be 0.05 to 0.5 ng/L, depending on the matrix. By treating the samples with glucuronidases/arylsulfatases, conjugates were amenable to analysis and the sum of conjugates and unconjugated steroids was calculated. In raw sewage, the median of the concentrations of the unconjugated steroids was 7 ng/L for EE2, 1.5 ng/L for E2, and 5.5 ng/L for estrone. After cleavage of conjugates, the medians of total steroids were 9.5 ng/L (EE2), 3 ng/L (E2), and 13 ng/l (estrone). Conjugates therefore contributed up to 50 % of the total steroid concentration in raw sewage. In treated effluents, the concentrations of steroids were much lower than in the raw sewage. The medians of free steroids were determined to be 0.3 ng/L for EE2, 0.2 ng/L for E2, and 2.5 ng/L for estrone. Overall the medians in the effluent were thus less than 10% of those in the influent. Conjugates still contributed significantly (40% and more) to the steroid concentrations (medians: EE2: 0.5 ng/L, E2: 0.8 ng/L, and estrone: 8 ng/L).     

Gewässergütebewertung und Bewertung von Abwasserfahnen in Rhein und Main auf der Basis mikrobieller Enzymaktivitäten

Quality Mapping of Surface Water and Assessment of Treated and Untreated Waste-water Inputs into the Rhine and Main River Based on Microbial Enzyme Activities Microbial enzyme activities are used for an extension of the traditional quality mapping of surface water. In the following study, the enzymatic parameters were proved and validated on samples from various creeks and rivers in Baden-Württemberg and on samples gathered from the Rhine and Main Rivers (Germany). The test parameters should also be used for the control and the preservation of the capacity of the biological self-purification, which is the only natural and essential process in drinking-water conditioning of surface water. Main subject of the surveys was the development of criteria for an assessment of the measured enzymatical inhibition effects. Therefore, classes of inhibition and indices of inhibition are defined.     

Über das Vorkommen von R-Plasmiden in Escherichia coli und koliformen Keimen aus Wasser und Abwasser Teil 1: Einführung und Bedeutung der übertragbaren Chemotherapeuti-karesistenz bei gramnegativen Keimen aus Wasser und Abwasser

Plasmids have been known for about 20 years. Meanwhile, there have been selected different species of bacteria, as Shigella, Salmonella, Gonococci and Haemophilusinfluenzae strains with a plasmid-infected resistance. The share of resistant microorganisms has increased due to the application of chemotherapeutic agents in the human and veterinary medicine and in the flora. As can be proved, the application of liquid manure on large areas and its frequently observed introduction of wastewater — also from hospitals — contribute to the distribution of the plasmids (resistance plasmids) in the environment.     

Vorkommen und Bewertung polyzyklischer aromatischer Kohlenwasserstoffe in einem mit kommunalen und industriellen Abwässern belasteten Fließgewässer

The river with a catchment of 5,400 km² is investigated over a length of 230 km at seven stations for the total concentration of six polycyclic aromatic hydrocarbons (PAH) and the total of three carcinogenic polycyclic substances (CPS) in the water by means of thin-layer chromatography. The maximum load occurs in the lower course downstream of large industrial wastewater introduction points with 5.1 μg/l polycyclic aromatic hydrocarbons, whereas in the upper course the maxima are at 2 … 3 μg/l polycyclic aromatic hydrocarbons for a mainly municipal pollution. The average daily load increases from 0.146 kg/d PAH and 0.048 kg/d CPS to 4.168 and 1.401 kg/d, respectively. In the flowing water there cannot be observed any self-purification concerning these substances, by an interconnected storage reservoir seston is reduced and thus also the PAC-concentrations are reduced by 50 … 60%. The PAH-concentration shows a significant positive correlation with the COD-Mn and the ammonium concentration. There is also a good agreement between the concentrations measured and the concentrations calculated from the wastewater load in the longitudinal section of the river.     

Nährstoffbelastung und Trophie von Talsperren der DDR Teil 1: Einzugsgebietsstruktur und Nährstoffsituation

Statistically secured relations between nutrient concentrations in the water and characteristics of the catchment areas can be proved for the storage reservoirs of the GDR. The o–PO₄ concentration during the full overturn in spring shows a close relation to the population density of the catchment area. Existing differences of concentration between drinking-water and industrial-water storage reservoirs can be attributed to different degrees of worthiness of protection of the catchment areas and to differences of the water morphology. The NO₃ concentration is closely correlated with the proportion of agriculturally used area in the catchment area. The mass ratio NO₃–N: o–PO₄–P mostly lies above the limiting range of the limitation of nitrogen (> 12: 1), so that phosphorus becomes the central quantity of a possible control of the trophic level. Especially for drinking-water storage reservoirs in the weakly eutrophic range the reduction of the P-load is necessary and it has a high trophy-improving effect here.     

Einfluß algenbürtiger organischer Substanzen auf Flockung und Filtration

The treatment of water from eutrophic lakes is disturbed by extensive development of plankton, which is caused by particulate algogenic organic substances and frequently also by dissolved ones. They are released by excretion, diffusion, cell destruction, separation of cell wall substances and metabolic processes in the course of the cellular reproduction in dependence on the physiological state of the algae. At a sufficient dosage of metallic salts as a flocculant, the extracellular organic substance (EOS) may act as an anionic flocculation aid in the concentration range of 1 … 2 mg/1 C. There is decisive the mass ratio: Me (metal as flocculant)/EOS (as TOC). Below a mass ratio Fe : TOC =2 … 3 the EOS disturbs the process of flocculation and filtration. Flocculation and filtration tests are carried out with the centrifugate of the culture liquid of eight algae species in flocculation test apparatus in order to clarify the disturbance of flocculation and filtration. The following essential reaction mechanisms influencing flocculation have been found: complexation of the metal-ions added as flocculation aids, precipitation reactions, neutralization of the positive charge of the metal hydroxo complexes of the flocculant with formation of surface complexes, increasing of the negative charge concentration and formation of protective colloids. The following counter-measures may be technically used with success: increasing of the addition of flocculant (Fe : TOC =2 … 3), shifting of the pH-value below the iso-electric point, addition of calcium-ions (1 … 2 mmol/l) and limited application of ozone prior to flocculation.