WQQDB - water quality and quantity data base Germany: metadata

The water quality and quantity data base Germany (WQQDB) was collected and put together at the UFZ.
It is based on a query to all federal states to provide discharge as well as nutrient and basic water quality metrics from their monitoring programs.
An overview on the providing agencies is given in a CSV-file (data_providers.csv).
This resulted in a collection of water quality and quantity time series from 14 federals states (without Hamburg and Bremen).

Quality data is available for 6086 stations. Time series are on average 11 years long starting from earliest 1954 (very rare), on average starting 1998. For Nitrate concentrations the average frequency is 7 measurements per year. All time series end 2016 latest.
Data is available for in-situ parameters (water temperature, pH, electrical conductivity, oxygen concentration and saturation), for nutrients (nitrate, nitrite, ammonia, mineral and organic nitrogen, total phosphorous, dissolved phosphate, total organic carbon, dissolved organic carbon)
and for sulfate, chloride, magnesium, calcium and suspended solids. Not all data is available for all stations.
For some stations measured discharge at the time of sampling is available. Based on spatial match and on stations naming connections to the water quantity stations as well as GRDC runoff data was established for 501 stations.

Quantity data is available on a daily basis for 894 stations. Time series are on average 40 years long starting earlies 1893, on average starting 1973.

The procedure, how data was imported, transformed and initially quality checked can be found in a TXT-file (procedure.txt).

The WQQDB is composed of two parts:
(1) The raw data archive that is archived in a repository at the UFZ: https://www.ufz.de/record/dmp/archive/7754/de/
(2) The metadata archive that contains information on the stations, time series length, number of measurements, data providers that is stored in HYDROSHARE