update:

EN* BQ* missing or new:

EN ISO 6222:1999 Water quality - Enumeration of culturable micro-organisms - Colony count by inoculation in a nutrient agar culture medium (ISO 6222:1999)
EN ISO 7027-1:2016 Water quality - Determination of turbidity - Part 1: Quantitative methods (ISO 7027-1:2016)
EN ISO 8689-2:2000 Water quality - Biological classification of rivers - Part 2: Guidance on the presentation of biological quality data from surveys of benthic macroinvertebrates (ISO 8689-2:2000)
EN ISO 9697:2017 Water quality - Gross beta activity in non-saline water - Test method using thick source (ISO 9697:2015)
EN ISO 10253:2016 Water quality - Marine algal growth inhibition test with Skeletonema sp. and Phaeodactylum tricornutum (ISO 10253:2016)
EN ISO 11731:2017 Water quality - Enumeration of Legionella (ISO 11731:2017)
ENV ISO 13843:2001 Water quality - Guidance on validation of microbiological methods (ISO/TR 13843:2000)
EN 14486:2005 Water quality - Detection of human enteroviruses by monolayer plaque assay
EN 16772:2016 Water quality - Guidance on methods for sampling invertebrates in the hyporheic zone of rivers
EN 16859:2017 Water quality - Guidance standard on monitoring freshwater pearl mussel (Margaritifera margaritifera) populations and their environment
EN 16870:2017 Water quality - Guidance standard on determining the degree of modification of lake hydromorphology
EN ISO 17943:2016 Water quality - Determination of volatile organic compounds in water - Method using headspace solid-phase micro-extraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) (ISO 17943:2016)
EN ISO 18635:2016 Water quality - Determination of short-chain polychlorinated alkanes (SCCPs) in sediment* sewage sludge and suspended (particulate) matter - Method using gas chromatography-mass spectrometry (GC-MS) and electron capture negative ionization (ECNI) (ISO 186


the missing are:

EN ISO 5667-16:2017 Water quality - Sampling - Part 16: Guidance on biotesting of samples (ISO 5667-16:2017)
EN ISO 9308-1:2014/A1:2017 Water quality - Enumeration of Escherichia coli and coliform bacteria - Part 1: Membrane filtration method for waters with low bacterial background flora (ISO 9308-1:2014/Amd 1:2016)
EN ISO 20227:2017 Water quality - Determination of the growth inhibition effects of waste waters* natural waters and chemicals on the duckweed Spirodela polyrhiza - Method using a stock culture independent microbiotest (ISO 20227:2017)

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