IDENTIFICATION AND RISK ASSESSMENT OF CENTRAL WATER SUPPLY SYSTEMS – CASE STUDY
ANCA ELENA GURZAU, CRISTIAN POP, OVIDIU TRAIAN POPA, IRINA DUMITRASCU
ABSTRACT. - Risk assessment of central water supply systems - a case study. This
paper presents methods for identification and risk assessment of central water
supply systems, exemplified by a case study of the central water supply system
in Luna locality, Cluj county during 2009-2010. System assessment was performed
by means of previous data on water quality monitoring and water samples analysis
for the parameters imposed by Law 458/2002 (audit monitoring) in the
laboratories of the Environmental Health Center. The main risk identified at
source was the significant water contamination with nitrates, in this regard
results did not show significant change of the raw water quality (drain) over
time. Occurence of nitrates in excess is of mixed origin in Luna water source,
predominantly telluric net and accentuated anthropogenic due to agricultural
practices in the area. In this respect, evolution of bacterial load was
significantly related to the drain positioning in an intensively exploited
agricultural area, the important increase of contamination being due to manure
application on upstream lands. Two kinds of hazards were identified at the water
treatment plant output and in the distribution network, as well as at the water
source: contamination with nitrates and bacteriological contamination of faecal
origin, the latter as a consequence of a completely inadequate chlorination.
Water in the distribution network of Luna locality represents low health risks
for small population groups (risk score 8), as characterized qualitatively on
the basis of monitoring. The compliance plan for preventing effects targets the
water source, treatment process, distribution network and health status
indicators.
Keywords: drinking water, risk identification, risk assessment