DUG WELLS 87 



The drip from pumps is a very common and dangerous source 

 of pollution. In the greater proportion of dug wells provided 

 with pumps the well is covered with boards or planks laid or 

 nailed over the top. No matter how carefully these platforms are 

 constructed cracks through which water can enter almost in- 

 variably exist, and it is a common occurrence to have the water 

 dropping or trickling back into the well whenever any is spilled 

 in pumping. The danger of this will be understood when it is re- 

 called that those stepping upon the platform to pump may have 

 just come from the barnyard or from manured fields, bringing 

 with them on their shoes more or less filth, part of which is left on 

 the planking and washed into the well by dripping water from the 

 pump or by the next rain. The wooden platform should be re- 

 placed by a water-tight cover made of iron, cement or other im- 

 pervious material. Cement covers are coming into use in many 

 localities and afford ideal protection. 



An ever-present cause of pollution in open wells and wells in- 

 sufficiently protected by coverings is the entrance of small animals. 

 It is a common thing for snakes, toads, mice and even rabbits to 

 penetrate through crevices and to fall into the well, especially in 

 dry seasons when the animals are compelled to make desperate 

 attempts to reach water. The remedy is an impervious well 

 cover fitted tightly to the curb. 



Dust is usually less dangerous than other sources of pollution, 

 but in dry seasons, when dirt from the street or barnyard is being 

 blown about, it may become of considerable amount and danger. 

 It is not uncommon to find several inches of black, foul-smelling 

 silt in the bottom of a well on cleaning, even though it may have 

 been cleaned only a year or two before. The dust may be kept 

 out by water-tight coverings such as are used to keep out pump 

 drippings. 



Seepage through the curb of a well at points above the water 

 level is one of the most frequent and most dangerous sources of 

 pollution. The slight thickness of soil through which the water 

 has percolated and the brief interval required for the passage 



