While previous studies have extensively focused on treating water in order to prevent corrosion, the
factors that affect stability of corrosion scales and the role they play on the quality of drinking water
within distribution systems have not been considered relevant until now. This investigation assessed
the response of corrosion scales from aged galvanized water distribution systems under alternative
water sources - groundwater and a blend of ground and surface water. A pilot project using pipes
from various distribution systems has been designed and monitored for variations in water quality.
The system is designed to simulate the actual operating conditions of a distribution system with 2,
20 and 40 years of service. Continuous monitoring of water quality has been recorded over the
course of 18 months. Results showed that under similar water characteristics each pipe responded
differently, suggesting that both the structure and composition of scale play an important role in
maintaining the quality of water within the distribution system. The introduction of a new water
source (the surface and groundwater blend) produced general reductions in iron release, turbidity
and color values. The influent water quality parameters that showed significant variations compared
to the base-line were dissolved oxygen, pH, alkalinity, and sulfates. In general, older pipes, which
have much more developed oxide scales, were more sensitive to water quality variations than the
new pipe. Overall, the main factors affecting water quality within the pipes were identified as
increase in temperature, increase in dissolved oxygen, increase in pH, decrease in alkalinity, and
increase in sulfates. Includes 8 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 320 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 14 |
| Published : | 06/17/2004 |
