Peter Howsam

Is the EU drinking water directive standard for pesticides in drinking water consistent with the precautionary principle

Regulations based on the precautionary principle should undertake a comprehensive assessment of all available scientific and technical data to identify sources of epistemic uncertainty. In the European Union (EU), environmental regulation is required to fulfill the principles established in Article 174 of the EU Treaty, such that it offers a high level of protection and is consistent with the precautionary principle. Pesticides in drinking water are currently regulated by the Drinking Water Directive using a maximum allowable concentration of 0.1 μg/L. This standard (a surrogate zero) was consistent with the precautionary principle when it was originally set in 1980 and remained consistent when retained in 1998. However, given developments in EU pesticide and water policy, international experience in regulating pesticides, and an increasing knowledge of pesticide toxicity, it can be argued that the level of epistemic uncertainty faced by regulators has substantially decreased. In this paper, we examine the extent to which such developments now challenge the basis of European drinking water standards for pesticides and whether, for substances for which there is good toxicological understanding, a regulatory approach based upon the World Health Organization (WHO) Guideline Value (GV) methodology would be more consistent with the principles underpinning European environmental policy.

Water law and the right to a basic water supply

Although there is no shortage of government rhetoric about the importance of providing clean drinking-water, nowhere is an individuals basic right to an adequate water supply enshrined in law. Peter Howsam calls for a global rethink on what constitutes this right — and emphasizes that it comes with responsibilities.

Sustainable use of groundwater for smallscale irrigation: With special reference to sub-Saharan Africa

Abstract Concepts of sustainability are discussed in relation to small-scale groundwater irrigation (SSGWI). The nature and important features of SSGWI are described, and the main endogenous and exogenous threats to the sustainability of this important farming activity are set out. The importance of groundwater monitoring and management, together with effective legislation and control, are highlighted. The potential conflict between promoters of rapid groundwater development for poverty alleviation and the proponents of a more cautious approach is discussed. The ‘Invisibility’ and limited area of SSGWI in semi-arid, sub-Saharan Africa are contrasted with their importance in what are otherwise drought-prone dryland environments.

Aspects of the occurrence and behaviour of iron bacteria in boreholes and aquifers

Abstract Iron bacteria are well known to borehole operators as the cause of iron biofouling—the build-up of orange-coloured slimes and encrustations on casing, pump and pipe surfaces. In addition to biofouling, these nuisance organisms play a part in: enhancing the corrosion of borehole, pump and pipe components; influencing the chemistry of polluting acidic mine drainage waters; and promoting the accumulation of soluble iron in groundwaters. This paper highlights the diversity of organisms which may be classed as iron bacteria, briefly describes the behaviour of iron bacteria in boreholes and aquifers and outlines the deleterious effects that their activity can have on the efficient functioning of groundwater abstraction systems. However, it would be wrong to classify iron bacteria only as a nuisance. There is potential for harnessing the activities of these organisms in a positive way and particular reference is made here to the benefits of biological removal of iron and arsenic from groundwaters.

Water policy and policy implementation

Even the most brilliant piece of policymaking will fail if implemented badly — and vice versa. The water and sanitation sector cannot afford to get it wrong: but is there the will to come up with realistic objectives that translate into sustainable programmes?

Identifying Adaptation Options and Constraints: The Role of Agronomist Knowledge in Catchment Management Strategy

Water suppliers in parts of Europe currently face occasional Drinking Water Directive compliance challenges for a number of pesticide active substances including metaldehyde, clopyralid and propyzamide. Water Framework Directive (WFD) Article 7 promotes a prevention-led (catchment management) approach to such issues. At the same time, European pesticide legislation is driving reduced active substance availability. In this context, embedding agronomic drivers of pesticide use into catchment management and regulatory decision making processes can help to ensure that water quality problems are addressed at source without imposition of disproportionate cost on either agriculture or potable water suppliers. In this study agronomist knowledge, perception and expectations of current and possible future pesticide use was assessed and the significance of this knowledge to other stakeholders involved with pesticide catchment management was evaluated. This was then used to provide insight into the possible impacts of active substance restrictions and associated adaptation options. For many arable crops, further restrictions on the range of pesticides available may cause increased use of alternatives (with potential for “pollution swapping”). However, in many cases alternatives are not available, too costly or lack a proven track record and other adaptation options may be selected which catchment managers need to be able to anticipate.

Biological removal of iron from well-handpump water supplies

Groundwater can be easily abstracted and safe to drink — if iron is present, it can also look and taste extremely unpleasant. Filter designs for use with handpumps have been around for a while now — is the latest model more user-friendly?

The examination of encrustations in an unlined borehole using the sidewall sampling technique

Abstract In borehole rehabilitation, engineers usually have limited access to information about the borehole condition and the processes involved. This paper describes the use of the sidewall sampling technique to gain information about some manganese encrustations which are considered to be adversely affecting the yield of a large-diameter, unlined, Triassic sandstone borehole in NW England. Trials with the technique proved successful and suggest that it is worth considering in any rehabilitation feasibility or implementation projects in which similar conditions prevail.

Iron in handpump water supplies: prevention or cure?

It is unlikely that the consumption of iron-contaminated water will result in health problems, however the taste and colour are putting consumers off this source. In order to ensure consumers do not choose more attractive, yet dangerously contaminated water sources, work is underway to explore the options available for removing the iron. This article addresses the need for iron removal and offers suggestions as to how it may be achieved.

Assumptions and realities in water and sanitation programmes

Water supply and sanitation programmes are based on many assumptions. Whilst there is much that is truth, the need to question them has never been stronger.