USGS Gauges

USGS Dead River gauge
USGS Androscoggin River gauge at Rumford

How to use the USGS Gauges

How to use the Dead River gauge:

The water level at the Dead River gauge ( at the Rt. 106 bridge, at Riverbend Campground in Leeds) is the same as the Androscoggin Lake level. This gauge is therefore very useful for checking on the lake level.

To read the gauge: take the "gauge height" and add that to 264.94 feet. The total of those two numbers equals the elevation above sea level of the water at that time.

Example: if the gauge reads 3.8 feet, add that to 264.94 -you can round it off for convenience to 265 - and the elevation at that time is 268.8 feet.

Explanation: the gauge is calibrated to the baseline elevation of 264.94 feet above sea level. So the gauge records the height of water above that point.

Some reference points:
Since the early 70's, the agreed upon "normal" summer water level is 269 feet above sea level. At 269, the rocks past the AYC are about 1 foot out of the water. At the usual winter water level of 271-2 feet, there is 1-2 feet of water on the Dead River Delta. When the Dead River reverses flow and floods the lake for more than 2 days, the lake level rises to 277-8 feet. The outer half Delta is flooded by 4-5 feet of water. The top of the new flashboards on the Dead River dam is at 278 feet. 2 year flood events (defined as a water level of 280 feet) flow 1-2 feet over the top of the flashboards. During the three big (100year) flood events of the century, 1936, 1951, and 1987, the lake rose to 289-91 feet- 16 feet over the top of the dam.

Other ways to use the gauge:

1. You can change the time span of the graph from 1-31 days. That will increase or decrease the amount of data given for each day. The gauge does not display data past 31 days, but the data is recorded and stored. You can get past data by emailing your request to the USGS. And be sure to thank them for their support of the gauge. The USGS sends the data to DEP, and they use it to calculate the amount of floodwater coming into the lake.
2. You can print out the graph by clicking on "presentation quality graph." A good way to keep a record of water levels is print the graph and make notes on it about rain or flood events, and water level indicators such as amount of beach exposed. etc.
3. The Dead River gauge only records elevation, not direction or amount of flow. The Rumford gauge, however, can be used to predict when the Dead River is reversing flow.

How to use the Rumford gauge:

You can look at the cubic feet per second (cfs) on the "discharge" graph of the Rumford gauge to predict the elevation and direction of the Dead River on the river side of the dam.

For example:
Flow at Rumford:
5300 cfs = without the dam, river would begin to reverse flow
8000 cfs = river water is at the top of the dam's floodgates. Lake outflow is blocked.
16,000 cfs = river water is at top of flashboards
22,000 cfs = river water overtops flashboards by 1-2 feet and flows into the lake

Click here to access the historic daily streamflow data for the Androscoggin River at Rumford.
You can access graphs of data from 1899 to 2003. (Last year's data, except for the previous month, is not available until the following year).

Some reference points: Before the dam was built in 1936, the Dead River reversed flow when the Androscoggin River was over 5300cfs.

From 1936 to 2002, floods over 16,000 cfs overtopped the dam.

With the new flashboards, floods over 25,000 cfs will overtop the dam ( assuming the flashboards do not break).

It is very informative to study trends by looking at graphs of selected months, years, or decades of data.
The graph is easier to use if you select the "arithmetic scale" instead of the "log scale" at "graphs of data."

It is not clear if there is a weather pattern of increased flooding since 1987, and if that would explain the decrease in water quality in the lake since the early 90's.
Roy Bouchard, DEP, has done some analysis of that and finds that it is too soon to declare a trend.
DEP Phosphorus Loading Report (Word document)

Note:
The E/PRO report on the hydrology of the Dead River reverse flow has much more detailed charts on the relationship between the various sizes of flood events, from 1 year floods to 100 year floods, the cfs in the river, and the direction of flow at the dam.