The creek
Archive →Five Mile Creek at the Republic gauge, one day at a time, back to the spring of 1988. That is long enough to know what an ordinary September looks like on this creek, and to say so plainly when this one is not.
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Season against season
Every year on file
How hard it rises and falls
—Two creeks can carry the same water in a year and be nothing alike to live beside. One comes up over a week and lets go of it over a fortnight. The other is in the yard four hours after the rain and back under the bridge by dark. That difference has a name, flashiness, and a way of being counted, and the gauge has kept enough days to say which of the two this creek is and whether it has been changing.
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What is being measured
Flashiness
Flashiness is the word for the difference between those two creeks. It is counted like this. Every day, note how far the flow went up or down from the day before. Add all those ups and downs together for the year. Then set that total against all the water the creek carried in the same year. A score of 0.60 means the ups and downs came to about 60 percent of everything that went past.
The score is a plain number with no units on it, so any year can be set against any other, and a creek against a river. Water off springs and wet ground is let out slowly and scores low. Water off roofs, roads and parking lots arrives all at once and scores high. That is why a rising score is usually taken as a sign of more building upstream. The measure is the Richards-Baker index, from a 2004 paper in the Journal of the American Water Resources Association.
What the water carries
—The gauge at Republic measures more than how much water is going past. It has also read the water itself every day since 1988, and that record reaches back further than anybody here has been watching.
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What is being measured
Specific conductance
How well the water carries an electric current, which rises with the amount of mineral dissolved in it: salts, metals, and whatever else the ground gives up. It is not a reading of any one substance and it is not a safety measure. It is the plainest number there is for how much the water is carrying, which is why the gauge has kept it since 1988. The USGS explains it here.
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Who else has been sampling
—The gauge at Republic is one meter in one spot, and most of this page is its record. It is not the only thing anybody has measured here. The Water Quality Portal is where the USGS, the EPA and the states put their samples, and for the length of Five Mile Creek it holds tens of thousands of them, taken by people standing in the water with a bottle, going back to the summer of 1952.
What is being measured
Dissolved oxygen
The oxygen carried in the water itself, which is what a fish is breathing and what everything living on the bottom of the creek is waiting on. It falls when the water warms and when something in the water is being broken down. The USGS explains it here.
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The record
The other half of it
What goes into the creek
How high the creek runs is one question about it. What goes into it is the other, and that has a page of its own: what goes into the creek sets out who holds a permit to discharge here and what the EPA says about the water.
Where this comes from The USGS gauge on Fivemile Creek near Republic, station 02457595. Every day since May 21, 1988 carries the mean depth and mean flow USGS publishes for it. The gauge's fifteen minute readings are online from October 1, 2007, and from then on each day also has its low and its high; before that the day's mean is all there is. The usual level for a time of year is the middle of every full year on file before this one, taken a week either side of the date. Seasons are whole months, the way the weather service counts them, so spring is March through May and winter runs from December into the new year. The last several months are provisional until USGS reviews them and can still move a little. The highest crest comes from the gauge's own peak record, because a flood can come and go inside a day. Republic sits upstream of all three towns, so what it reads is broadly what comes through Brookside, Cardiff, and Graysville after it. Specific conductance and water temperature are the same gauge's other two daily records, kept since September 1988 and gathered here into whole years. A year to date is left off, because the months it is missing are the cold ones and it would read high against every finished year for that reason alone. How hard the creek rises and falls is worked out from those same daily flows and nothing else, as the Richards-Baker index: every day's change in flow added up across a year and divided by all the water that went past in it. The samples are somebody else's, off the Water Quality Portal, which is where the USGS, the EPA and the states put theirs. The ones here are every water sample taken inside the two hydrologic units that make up Five Mile Creek, which is the same stretch of water the discharge page counts permits along. A sample means somebody went and took one. ADEM has also left a recording instrument in the water at eight of these places, and it logs itself every few minutes for weeks at a stretch, so its readings are counted apart from the samples rather than added to them.