Difference between revisions of "管道补给"

Revision as of 08:44, 28 August 2015

2006年6月莫桑比克希莫尤，使用手钻钻洞为管道补给系统做准备。图片来源：Arrakis。

管道补给。津巴布韦。图片来源：H. Holtslag

管道补给成本低，它结合了人为填洞和铺设排水管道。排水管道穿过压实的表层土。之前雨水通常会蒸发或者流入河水，但现在能渗进土壤补给含水层。

管道补给系统由塑料软管或PVC管道组成，直径为20-30毫米。这些管道铺设在人为钻取的洞中、抽水井的上游、自然集水处或人造池塘中。雨水填满池塘后，必须先等几个小时才能打开排水管道，以便处理污垢。水进入管道之前先经过过滤管道。根据压实表层土的面积，管道长度为5-10米不等，而且不会到达含水层。

由于池塘面积不同，每次下雨将为含水层补给大约2-10立方米的水。地下水的水量和水流模式决定旱季时抽出的水量。

当地的地质状况决定具体要求、成本和时间：如果没有石头和巨砾，一天可钻取一个深度为10米的洞，如果使用钻孔机（如螺旋钻或手钻 - 常规）则无需一天。

Prior to placing the recharge tubes, testing is needed to determine the best sizes of tube, depth, maximum capacity of recharge, etc.
Maintenance consists of unclogging the drainage tube by swabbing: moving a stick with a cloth up and down the drainage hole.
Before recharge systems are applied on a larger scale, their effectiveness in a given context should be further investigated by means of smaller pilot systems.

Total costs per system (drilling, tubes, labour): US$ 5 - 30.
Step auger or Baptist drill set for holes up to 12 m (can be used for many holes): US$ 75.

If the holes are drilled by families themselves, the costs can be minimised.