ÖNORM M 6232

This Austrian Standard (ÖNORM) contains guidelines to conduct ecological studies in permanently or temporarily flowing surface waters. It shall be understood as a guideline for studies which aim to assess rivers according to ecological criteria (water as habitat) in connection with water resource management, river water quality monitoring, river protection, river rehabilitation, and the maintenance of rivers as landscape elements. An ecologically oriented ÖNORM demonstrates to the educated specialist ,the state of knowledge in describing river ecosystems; it compiles the methodology used to make ecological Observations and lays out the normative prerequisites for the assessment of the results. This senres to standardize study strategies and helps clarify the conclusions drawn from investigations of riverine ecology. Establishing minimum data requirements concerning the most frequently met Problems leads to standardized methodologies for ecological assessments. Ecological assessment utilizes methods that compare riverine habitats which to a large degree have not yet been influenced by man - the pristine conditions of the river - with the current conditions of the riverine environment. This assessment strategy incorporates the ecological values of biotope and species protection and follows the normative prerequisites of the Austrian Water Rights Act and the Proposal of the European Union for a Council Directive establishing a framework for EC water policy (clause 7). In this Austrian Standard, all environmental factors and groups of organisms which are important for the ecological assessment of rivers (17) are, in principle, included. Groups of organisms which are relevant to the practice, and can be handled methodologically, have been more extensively described, due to the more advanced state of knowledge. The application of this ÖNORM extends to, among other things, studies corresponding to the Water Rights Act 1959 (WRG 1959) - especially those studies which record and describe the ecological integrity (39) of rivers - and studies that address questions concerning river water quality (22), self-purifying capacity, and the preservation of natural conditions of the river and bank areas which are necessary to preserve the ecological integrity (39) of a river. River-related questions concerning the initiation of ecosystem protection within the environmental protection legislation of individual federal provinces are also subject to this ÖNORM. This ÖNORM further contains a methodological basis for the description of the "Natural ecological Status" by a body of surface water as well as the assessment of the "Surface water status" by a body of surface water according to the proposed directives of the EU (consultation draft 4/12/96; See clause 7). Studies in the described manner are additionally required for the - assessment of the effects of water-engineering measures and flood control such as: impacts on the dynamics of the river; impacts on the diversity of in-stream structures and current velocities; impacts on the ecological continuity of the river channel System; - assessment of the ecological effects of changes in the hydrological regime of the river; - assessment of the effects of hydropower development such as: impoundment; water abstraction; hydro-peaking ; - assessment of changes in the temperature regime and discharge of sewage; ...