Dow’s Great Swamp, as the name implies, was hardly a paradise. Throughout the construction of the canal, “swamp fever” was a routine complaint, likely referring to some form of malaria; many of the workers died from this disease, and both John MacTaggart and Colonel By himself were sick with it at various points.[1] MacTaggart, in fact, had to leave Canada after one particularly bad bout. More importantly, the swamp was nearly totally impassable and certainly could not be used as part of the Canal. By’s solution was draining the swamp through the use of the embankments mentioned in the first post on the subject. The purpose of this post, then, is to explain how this was done; how can a swamp be drained?

Dow's Lake
Dow’s Lake in Summer. Image source: LAC (see below)

 

Humans have been draining swampy areas for millennia, with possibly the earliest example found in the Indus River Valley from around 2500 BCE.[2] Later, the Romans and then the Dutch were particularly adept at draining land in low-lying areas of their territory.[3] However, large-scale drainage did not come into use until the nineteenth century, with the advent of the Industrial Revolution; the accompanying growth in population which necessitated agricultural expansion and a rapid improvement in manufacturing technologies fueled development in drainage techniques. Prior to this period, subsurface drains made of pipes, sticks, stones, and other materials had been the most common drainage method; though effective, these drains required significant labour and continuing maintenance.[4] Tile drainage, a more efficient method which used a pipe made of tiles and clay to funnel water out of inundated areas, came into heavy use as the Industrial Revolution reduced the cost of manufacturing the tiles, but had not yet come into heavy use when Colonel By arrived.

When it came to Dow’s Great Swamp, however, these methods were impractical. For one, the above methods were developed mainly for especially wet agricultural areas, not unfettered wilderness as at Dow’s. Dow’s was simply too wild to dig the number of tunnels necessary, and its size meant it would have required far too many tunnels in any case. Secondly, an advantage possessed by the Canal builders was that they were already reshaping the terrain in the region, and could therefore use their existing labour force for the construction of the embankments. Furthermore, the swamp was fairly low-lying and so the ground was likely too wet to dig the tunnels in the first place. This had also been the case in the Netherlands, a famously low country, and embankments were a popular method there also. In these situations, the best way to dry an area was to stop the water from reaching it.[5] This is what embankments accomplished, often when paired with ditches. At Dow’s, By had the advantage of having already constructed a dam, which had shut down a great deal of the water flowing into the swamp; he then used the embankments to finish the job.[6] That, as Colonel By discovered, is how to kill a swamp.

References:

1 Legget, Robert. Rideau Waterway. Toronto: University of Toronto Press, 1972. 51.

2 Ritzema, H.P., ed. Drainage Principles and Applications. Wageningen, Netherlands: International Institute for Land Reclamation and Improvement, 1994. 24.

ftp://ftp.gps.caltech.edu/pub/avouac/Tibet_Holocene_Climate/drainage_princ_and_appl.pdf

3 Pavelis, Goerge A., ed. Farm Drainage in the United States: History, Status, and Prospects. Washington, D.C.: U.S. Department of Agriculture, Economic Research Service, 1987. 13-14.

https://books.google.ca/books?hl=en&lr=&id=agEUAAAAYAAJ&oi=fnd&pg=PA13&dq=swamp+drainage+methods&ots=uiUu2QWS-H&sig=pYG1A01IoodGXv3sX-TJjPCed-0#v=onepage&q&f=false

4 Pavelis, Goerge A., ed. Farm Drainage in the United States: History, Status, and Prospects. Washington, D.C.: U.S. Department of Agriculture, Economic Research Service, 1987. 14.

https://books.google.ca/books?hl=en&lr=&id=agEUAAAAYAAJ&oi=fnd&pg=PA13&dq=swamp+drainage+methods&ots=uiUu2QWS-H&sig=pYG1A01IoodGXv3sX-TJjPCed-0#v=onepage&q&f=false

5 Pavelis, Goerge A., ed. Farm Drainage in the United States: History, Status, and Prospects. Washington, D.C.: U.S. Department of Agriculture, Economic Research Service, 1987. 14.

https://books.google.ca/books?hl=en&lr=&id=agEUAAAAYAAJ&oi=fnd&pg=PA13&dq=swamp+drainage+methods&ots=uiUu2QWS-H&sig=pYG1A01IoodGXv3sX-TJjPCed-0#v=onepage&q&f=false

6 Legget, Robert. Rideau Waterway. Toronto: University of Toronto Press, 1972. 178.

Image source: http://collectionscanada.gc.ca/pam_archives/index.php?fuseaction=genitem.displayItem&lang=eng&rec_nbr=3359086&rec_nbr_list=3359086,3318619,3326102,3232979,3402981,3318616,4292848,4292851,4124461,2136348