Bantam Staff Gauge

    The Staff Gauge at Chickadee Bridge, seen in figure 1, is a simple technique used to monitor the depth of the Bantam River. The gauge was installed in May of 2016, and weekly measurements have been taken ever since, which graphed out can be seen down below in figure 3. The purpose of this project is to monitor the volume of water that flows down Bantam River - directly feeding into Bantam Lake. As Bantam River is the major tributary of the Lake, alterations in its flux - or volume of water moving through the river in a given time - can have major consequences on the volume of water in Bantam Lake.
Figure 1: Staff gauge at Chickadee Bridge, close up on top, farther out view on bottom

    Runoff into the river, specifically high levels of nitrogen and phosphorous, is a key component in lake management moving forward, as it is possibly related to the increasing cyanobacteria blooms in previous years. This is why, moving forward White memorial will be doing some collaborations with the Bantam Lake Protective Associations to monitor water quality. The Staff Gauge is the first step in monitoring the flow of the river to better understand the amount and type of water moving into the Lake. The next monitoring step involves taking storm water samples around the Lake after large rainstorms. This will indicate whether a high flow event could be correlated to a high nutrient load event, which may correlate to cyanobacteria blooms. Thus monitoring and better understanding the water flux relationship that Bantam River has with Bantam Lake allows for better management of the Lake as a whole.
    The depth of the river also alters the water levels in the surrounding wetland ecosystems of the area. For example, a high, unexpected flow event in the river could flood out Marsh Shorebird nests, who nest right around the floodplain in the wetlands. An example of a Marsh Bird found on the property is the Virginia Rail and can be seen in figure 2. This kind of disturbance can alter the Marsh shorebird activity for the year, and if it occurs multiple times could alter the residence of these protected birds over time. Thus, the staff gauge was installed with the hopes of understanding how Bantam River affects its surrounding ecosystems as well as Bantam Lake itself.

Figure 2: Virginia Rail in a marsh

Figure 3: Mapped out water depth at Chickadee bridge for roughly the last year

    Interesting results from the staff gauge can already be extrapolated. Figure exhibits an up to date map of the water depth at Chickadee Bridge. There are a few areas of interest within this first year of data. The first point of interest is the steady decline of depth from May 3rd, 2016 at 8.12 feet to October 18th, 2016 at 6.1 feet, when there was a drought occurring. Increased precipitation lead to the eventual recovery of the drought, which on December 1st 2016 with a depth of 8.3 feet. The times where data was not taken - exhibited by the white bars in the below graph - occurred when ice and snow covered the river. The last area of interest occurred on April 8th, 2017, where the water level reached its highest level since the inception of the project at 9.38 feet. This was correlated with the melt of the snow and ice that occurred right beforehand, which was caused an increase in the flow. There was also a rain event that occurred, which increased the melt of the snow, adding to the water flux. The lack of vegetation at the time also increased run off. All this data in the last year indicates that this project is working - we can see the fluctuations in the river from difference incidences throughout the year. The volume of water clearly changes throughout the year, and by monitoring it we can seen how the river varies throughout the years, and use knowledge towards lake management.
    An extension of this project would be to begin adding more gauges on the river, to see how tightly correlated the river and the lake are, as well as adding more gauges farther upstream in the river to see how the volume of the river itself fluctuates over a given distance. There is also a possibility to adding gauges to other smaller tributaries in the lake, to fully exhibit how the Bantam River itself is major to the volume fluctuations in the Lake.

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