The Sand/Spill Gates at Magrath were an integral part of the operation of the irrigation canal. When you slow the waters of a river by diverting it into a canal, you automatically reduce the load of sediment (sand and silt) that the stream can carry. This load is dropped into the bed of the canal early-on, and must be periodically flushed from the system or the capacity of the canal to flow water will be greatly reduced. This was the function of the structures at the Sand/Spill Gates; to periodically flush the sand/silt from the canal system which had a tendency to accumulate there. This fine sand was often used to create the durable concrete of the day.
Looking north from the canal, one can see the straight (unnatural) course of the Pothole Creek. The original river had a naturally meandering course, that took its seasonal flow uncomfortably close to the bank of the newly constructed canal, and this heavy seasonal flow could result in a wide flood plain. To eliminate the threat of erosion to the newly constructed canal and to reduce the hazards posed in annual flooding, the bed of the river was straightened to run approximately north-south. A benefit of this early decision was that in later years, one of the oxbows left at the side was used to construct the popular Fish Pond and its associated campground area.
In looking at the photo facing north, one can see two prominent landmarks on the skyline (both now gone) of the early Town of Magrath—the Public School with it big bell; and to the left of this, the tower of the Assembly Hall, built about 1914.
+ existing & alternate photos
Looking north from the canal, one can see the straight (unnatural) course of the Pothole Creek. The original river had a naturally meandering course, that took its seasonal flow uncomfortably close to the bank of the newly constructed canal, and this heavy seasonal flow could result in a wide flood plain. To eliminate the threat of erosion to the newly constructed canal and to reduce the hazards posed in annual flooding, the bed of the river was straightened to run approximately north-south. A benefit of this early decision was that in later years, one of the oxbows left at the side was used to construct the popular Fish Pond and its associated campground area.
In looking at the photo facing north, one can see two prominent landmarks on the skyline (both now gone) of the early Town of Magrath—the Public School with it big bell; and to the left of this, the tower of the Assembly Hall, built about 1914.
+ existing & alternate photos
Then and Now: A Collection of Photos of the Magrath Sand/Spill Gates