In this age when IT is king and sophisticated computer modelling is common place, is there still a place for low tech science such as hydrometry ? Is this merely a costly use of manpower and time, yielding only marginal gains in productivity, requiring sophistic justification, of limited interest in a period of increasingly rare money?

We've got to take a stand: the overwhelming majority of mathematical models err in their calibration data. Today it is less expensive to create a model than to go out into the field and collect real data. If we scratch beneath the surface of some of these hydrological projects- and certain recent scientific committee opinions remind us of this- we can quickly see the problem and underline the extent to which derived default hypotheses can have consequences not only in terms of risks but also in terms of possible cost overruns.

The use of hydrological data is growing rapidly. Beyond the needs for modelling purposes, water use regulations have pushed us to better judge the effect of projects in observing an area and subsequently its fluctuations. Finally, the development of irrigation, using an increasing portion of seasonal discharges, made it necessary to manage this water use, which meant a better real time understanding of discharges.

The quality charter, created by the HYDRO database user committee, shows that the hydrometry techniques have greatly evolved over the last fifteen years. There has always been an overriding concern for traceability, so that tomorrow's enlightened critics will be able to obtain current as well as historical data.

In this charter, several improvements have been planned in order to ensure a maximum quality for hydrological data. It is therefore an everyday work guide whose vocation is to serve as a commitment to quality for hydrometry services.

The originality of this charter, then, is that it is designed firstly for field personnel, although technicians and engineers will surely find some interesting surprises herein, and there is even something for the decision makers and financial experts whose curiosity takes them beyond the realm of educational illustrations.