Groundwater quality: introduction

Introduction

Maintaining the quality of Dutch groundwater is vital given the uses to which it is put. In the first place, groundwater is a vital source of drinking water. In addition, groundwater quality has a major influence on ecosystems. Groundwater quality is under pressure from eutrophication, and to a lesser degree from acidification, desiccation and toxic and hazardous substances.

A notable characteristic of the groundwater compartment is that decades may elapse between the application of a contaminant on the soil surface and the detection of an excessive concentration in the groundwater as a result. The more distant in time contamination is, the deeper the effect on groundwater will be now.

Recent pollution on the ground level affects the quality of the uppermost groundwater (the top metre).
Contamination from approximately ten years ago will be manifest in the shallow groundwater (at a depth of 5-15 metres).
The medium-deep groundwater (15-30 metres depth) is now suffering the effects of contamination introduced a few decades ago.

Contamination can therefore continue undetected for years and, once the impact has been detected in deeper groundwater (drinking water, for example), it will in turn take a long time before the quality improves. This means that extra vigilance is required in the area of groundwater quality.

References

VROM (1997). National Environmental Policy Plan 3. Ministry of Housing, Spatial Planning and the Environment, The Hague.
VROM (2001). National Environmental Policy Plan 4. Working on sustainability: Where there's a will there's a world. Ministry of Housing, Spatial Planning and the Environment, The Hague.

Groundwater quality: introduction

Introduction

References

Relevant sections and indicators in the Environmental Data Compendium