secondary water pollution

These plant residues and sediment carrying a certain amount of pollutants, if not promptly removed from the water, may be pollutants will re-enter the water body to cause secondary pollution, thus affecting the purification of the wetland system at the same time lead to resource waste.

这些植物残体与底泥携带有一定量的污染物，如果不及时的从水体中移除，可能污染物会重新进入水体中造成二次污染，从而影响人工湿地系统的净化效果，同时造成资源的浪费。

The hot and cold water pipes can ensure the water quality without secondary pollution.

自来水的冷热水管,保证水质无二次污染.

A considerable part of the money supply facilities for a long time without maintenance, management, secondary water supply facilities and frequent overflow pipe leakage; while water pollution is very serious.

有相当一部分供水设施长时间无资金维护、管理，使二次供水设施时常发生溢流和管网漏失；同时水质污染也十分严重。

Corrosion scales could form on the pipe wall that serving for long time. Drinking water can suffered from secondary pollution, and hygeian situation directly influences supply water quality.

服务年限长的供水管道内壁会形成腐蚀物，使饮用水受到二次污染，供水管道的卫生状况将直接影响水质。

High-pressure features, first to ensure the water is secondary pollution.

高压等特点, 首先确保了饮用水不被二次污染.

For the house-hold water storage , the main factor is secondary pollution on water stored.

而在家庭储水方面, 主要是存在二次污染的风险.