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Streamflow in CT Overview and Drought Conditions

Connecticut Streamflow and Groundwater Overview

Know Your Flow!
We update this webpage with the latest information weekly.

CT Conditions At A Glance

(Click on any graphic below for more information)
Streamflow in CT Now
(click map to go to the data page)

 [color code for]  color code for  color code for color code for  color code for  color code for  color code for               [color code for]         
   High Flow     Low Flow        Not Ranked
CT Current Streamflow. Click to go to source page.
US Drought Monitor Map of CT
(click map for details)
Current US Drought Conditions. Click to open
                  source page.
The U.S. Drought Monitor is jointly produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the United States Department of Agriculture, and the National Oceanic and Atmospheric Administration. Map courtesy of NDMC-UNL.
Map of Below Normal 28-Day Average Streamflow

Recent Flow At a Typical CT Stream
(click graph for details)

Link to Burlington Brook flow data
Groundwater Level
(click graph to see more well data)
USGS monitoring well. Click to see more.
Check your forecast here
(click map to go to state weather page)
Link to NWS graphic page
Graphic courtesy NOAA showing CT area watches and warnings if any.

Mar 23, 2017 Update

Summary (details follow)

The U.S. Drought Monitor downgraded the areas of Connecticut rated Extreme rating two weeks ago, and this week lowered the severity rating of the eastern 12% of the state to Abnormally Dry. As of March 21, 42% of the state was rated Severe, 46% Moderate Drought.  As a percentage of area, CT remains the most drought-afflicted state of all 50.

Streamflow varies widely across the state. It is near normal where temperatures have allowed the deep snow from recent storms to melt, below normal elsewhere. The improvement in groundwater levels has slowed, and remains low for half of the state. The worst drought since the historic drought of the 1960s continues. 

The Interagency Drought Workgroup (IDW) met on Mar 8, and was expected to not recommend any changes to the state's drought alert level. The Drought Watch would then continue for six CT counties; Drought Advisory continues for the eastern two counties. The state is still requesting all residents to reduce their water use by 10 to 15%.

Most, but not all, water utilities have ended mandatory conservation measures.

Due to the ongoing drought conditions, the Department of Energy and Environmental Protection (DEEP) issued a Public Notice that it "...suspends the minimum stream flow standards ... commonly known as the 'spring freshet' release standard, for the period of February 15, 2017 to March 15, 2017.... Questions regarding this action may be directed to Doug Hoskins, ... 860-424-4192, douglas.hoskins@ct.gov." For more information, please see the IDW freshet discussion from Jan 20.

Due to the lack of the Spring freshet, many more streams, when compared to their records for the date (see below), are exhibiting low flows between storms. On March 9, 76% of CT rivers and streams measured by the US Geological Service (USGS) were experiencing low baseflows, compared to 19% the previous week.  An alphabetical list of low-flow rivers is below. Until this week the graphs for most (not all) river and stream gages were showing a normal pattern of about equal areas above-average flow when it rains (or when there are days with rapid snowmelt), then below-average between storms and days without snowmelt. For those streams where snowmelt or mandated releases regularly created higher flow in previous years, the current flow is well below average.  The 28-Day Average Streamflow map from the USGS categorizes most of Connecticut as well below normal because "normal" for that period includes high flows in previous years from spring freshet releases from dams that did not occur this year. See Streamflow Graphs and Storms below for more explanation.

Dry conditions that cause flow to be below average more often than it is above average is affecting stream life throughout the state. Fishermen have reported long stretches of rivers with no catch at all. Whatever dormant life is left on our stream bottoms will be lost if flow remains too low to prevent the stream from freezing solid when temperatures get unusually cold. This is different from the common winter fish kills explained in fact sheets from CT DEEP.

Click here for the USGS Connecticut stream gage web page with graphs of flow from every gage for the past 30 days compared to their daily average flows.

Public Water Supply Information

Your water utility and town web pages are the best sources of information on water use restrictions that apply specifically to you. The Department of Public Health's (DPH) Reservoir Data monthly web page dated Feb. 6 stated that capacity was at 87% of normal, the percentage reported on their Monthly Reservoir Status Summary for January. (Note that "normal" for January is 91% of capacity.) The 87% of normal is based on reports from 34 large water systems that use reservoirs. That percentage means those reservoirs averaged 80% of capacity. Most of those water utility companies had issued water use restrictions or asked for voluntary conservation. The DPH also has a separate list of Public Water Systems with water use restrictions, last updated Dec. 12, 2016.

Bristol Water Company continues its mandatory restrictions. New Britain is buying water from the Metropolitan District Commission.

Aquarion maintains on its website a weekly updated water usage report that includes customer usage trends, system transfers, system capacities, days usable storage remaining, and precipitation. Their graphs and charts indicate conditions are near or even above their trigger levels for water usage alerts.

Greenwich, Stamford, Darien, and New Canaan are working with Aquarion on a water-demand study that could be completed next month. They are examining the overuse of water that, combined with years of below-average rain and snow, has caused a statewide drought. The study could result in permanent water conservation guidelines. Area residents with their own wells are also expressing frustration with water conservation measures.

Groundwater

The water table normally reaches its highest levels from this time of year until late spring. Over the last few weeks the water in most wells has either slowed its steady rise or has leveled off. Day to day, groundwater has been moving up with rainfall and snowmelt, but then it drops again. If this year's plateau has been reached, it does not bode well for our rivers and streams if drought conditions intensify again. 

On March 16, two of the six real-time monitoring wells run by the USGS with multi-year records was reporting a water table lower than any daily averages for the date for those wells. Three others, though not setting records, were lower than 75% of their averages for the date. The other well is near average but falling. These numbers have not varied much in the past month.

Until the past few weeks, all eight live-data stations were showing the water table recovering steadily from the their lowest levels in September. Until November, more stations were breaking low-water-level records than those that were merely very low. Some well levels have been rising or falling depending on the weather. Most however are showing that the depth of the water table is still trending upward but that trend is leveling off.

The USGS Connecticut office this year added live-data access to two additional wells, in Clinton and Salisbury. The live data displayed by these go back to August of last year, but comparisons to their monthly measurements of previous years can be made using the USGS's Groundwater Watch website. For example, the March 16 measurements from the Clinton and Salisbury wells were close to or above normal for their March measurements going back decades.

On March 16, the most recent measurements at 40% of the 70 wells on the Groundwater Watch website were near or above normal; 36% were labeled below normal; 21% were much below normal. However none had measurements lower than any previous years measurement at those wells going back 16 to 20 years. The number of wells reported below normal are a little higher than in previous weeks.

The water level in streams and rivers between storms depends on the flow of water out of the ground into the stream channel. The higher the water table, the more water is available to keep streams flowing. During a drought, smaller upland streams dry up faster than the larger rivers (details below). An occasional brief, powerful rainstorm does not do much to help groundwater levels rise. The rain falls faster than the ground can absorb, and thus much of it becomes stormwater runoff. In that situation, public water supply systems that depend on reservoirs are affected less than those with wells because the runoff is collected by the reservoirs. How much groundwater is contributed by snow depends on several factors including slope, rate of snowmelt, and whether the ground beneath the snow is frozen or saturated.

There has been an apparent pattern for the last five years in which normal groundwater levels in winter and spring have alternated with well-below-average in summer and fall. Click the graph to the right for a larger version in a new tab of a modified USGS graph. There are two trends of great concern. One concern is that that the below-normal levels in Summer and Fall got worse in each of those years. The other concern is that the water table has not recovered this year as it has in previous years.  Five years is not long enough to make any statistically valid conclusions about climate, however, and those station records only go back seven to 14 years. Click here to see all the USGS graphs for their real-time groundwater measurements that compare levels from the last four years to the median levell for each day of the year (lots of data, so it takes a long time to load). USGS manually measures other wells once a month or so, and a quick look at those records verified the possibility that this pattern may apply to all our groundwater.

The USGS Groundwater Watch website is an excellent source of data for examining historic and current trends. The map of CT (example below) is color coded the same way the USGS Connecticut streamflow map is colored to show how the most recent measurements compare to historical records for each station. Graphs can be made to chart water levels for all 70 wells.

map of CT gw, link to website

Precipitation Patterns

(See also climate news: Climate Change Threat to Both the Natural World and to Human Civilization)

Why is Connecticut still in Drought Watch and Advisory status? If the deep snow snow from recent storms melts rapidly, we will have the same situation the US Drought Monitor narrative summary the Northeast for February 28 described:

"...the much warmer-than-normal temperatures rapidly melted a significant amount of New England snowpack. Snow melting this fast pretty much just ran off into the rivers and streams as opposed to slowly entering the ground to recharge the ground water."

According to the National Weather Service Advanced Hydrologic Prediction Service, precipitation over the last 30 days has been about half of what we would normally get at this time of year in the eastern part of the state, around 75% of normal for the western half. At the beginning of 2017, near-average precipitation had been gradually improving long-term streamflow and groundwater levels. In January and February however, precipitation was fairly heavy but infrequent, averaging out to near-normal 30-day amounts. Periods of unusually heavy precipitation like this do not compensate for unusually dry weather even if they average out to normal because heavy rain does not all soak in to recharge groundwater. In March however, below-normal precipitation has been once again affecting groundwater and stream levels. If snow melts slowly enough that most of the water infiltrates the soil, it can help to improve long-term drought conditions, but the rapid melting early in the month did not replenish groundwater very much. Go to this link for detailed maps and data.

For most of 2016, storm tracks brought precipitation out to sea or north of us because a persistent high-pressure system called a blocking pattern was diverting weather fronts and storms. It was only when that blocking pattern moved away for short periods that some weather systems came over Connecticut, creating temporary returns to more normal rainfall. That normal precipitation did not end the drought due to the serious long-term rain deficit, but it kept it from getting worse for a while. Streamflow between storms continued to drop to low levels, however.

This is the same bad situation that we had in 2015-2016 (see below), caused not only by less total rainfall than normal over a long period of time but also by the intensity of the rain we did get. Not all drought conditions went away last winter. As our climate changes, heavy precipitation events are becoming more frequent. Heavy rain does not recharge groundwater aquifers as much as the same amount of rain over longer periods would. 

Rain? The National Weather Service's one-week forecasts show some rain and snow with temperatures that could allow a slow melt of the snowpack. This would be best to relieve long-term low-flow stream conditions because it would raise the water table.

Their long-range (16-day) computer models are predicting normal precipitation and temperatures, good news for our rivers unless the rain comes as unusually heavy downpours.

Each month, the NWS Climate Prediction Center issues analyses of global atmospheric conditions that could influence general temperature and precipitation patterns. Their March 16 analysis for trends through May show equal chances for above-normal, for normal, and for below-normal precipitation. Above-normal temperatures are a little more likely than normal temperatures. This is pretty much the same three-month forecast we have seen for the past year, but actual precipitation was much lower than normal. The NWS Climate Center's prognostications for the Summer, however, give a 40% chance for above-normal rainfall, a 33% chance for normal, and a 27% chance for below normal precipitation. That prediction for June, July and August was the same for the previous three months.

Lowest Baseflow Streams and Rivers in Connecticut

The USGS data file we usually use for assessing low flow rivers has not been available since Mar 16.  Here is our analysis from Mar 9:

Water levels and flow rates in our streams dropped unremarkably after recent storms, falling to levels similar to what we have seen for the past month. However, when comparing streamflow to previous years' records for March 9, we found that 47 of the 62 (76%) Connecticut rivers and streams measured by the USGS (listed below) were experiencing low flows*. There were 12 the previous week. To see the status of any them right now, click the station's URL below.

Did the water from 35 streams get diverted over the course of a week? Of course not. What we are seeing is the lack of the Spring freshet, the expected flush of water from melting snow and from releases from dams. In previous years, many stream gage records show a distinct rise in flow at the beginning of March, so the average flow for the date from many years of data from those stations is higher than than in February. This year however, the bulk of the little snow we got melted early from abnormally warm temperatures in February. Also, DEEP issued a Public Notice that it "...suspends the minimum stream flow standards ... commonly known as the 'spring freshet' release standard, for the period of February 15, 2017 to March 15, 2017.... " For more information, please see the IDW freshet discussion from Jan 20.

On February 24, there were 7 low-flow rivers on our list, the same number as the previous week. That was a significant improvement from February 14 when there were 23, and from February 6 when there were 34 low-flow streams. In January the number ranged from 27 to 35. During most of 2016, there usually were 50 to 60 low-flow streams; on December 23 there were 53.

As streamflow between storms continues to drop at a time of year it is usually increasing, we have to be concerned about the recovery of our streams' ecosystems from drought conditions. This is especially true when the flow is lower than any record for the date, such as the seven stream gages in bold red below that were setting records on Mar 16. There were five last week.

On March 1st, only one stream gage was reporting flow lower than any record for the date, on the Saugatuck River. The flow in the Saugatuck has been setting low-flow records since November. That was also the only record-breaker the previous week, down from two of them each of the two weeks before that. Until Mar 9, the number of record-low streams had been improving since Feb. 6 when there were seven record breakers; In January the number of record-breakers ranged from five to nine. The number of record breakers were even higher for most of 2016; for example, there were 15 on Dec. 23.

Lowest Baseflow Streams and Rivers in Connecticut on Mar 9

Station Name
Station Website
ASPETUCK RIVER AT ASPETUCK, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01209105
BROAD BROOK AT BROAD BROOK, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01184490
BUNNELL BROOK NEAR BURLINGTON, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01188000
BYRAM RIVER AT PEMBERWICK, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01212500
COGINCHAUG RIVER AT MIDDLEFIELD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01192883
EIGHTMILE RIVER AT NORTH PLAIN, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01194000
FARMINGTON RIVER AT TARIFFVILLE, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01189995
FENTON RIVER AT MANSFIELD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01121330
FIVEMILE RIVER NEAR NEW CANAAN, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01209761
FRENCH RIVER AT NORTH GROSVENORDALE, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01125100
HOCKANUM RIVER NEAR EAST HARTFORD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01192500
INDIAN RIVER NEAR CLINTON, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01195100
LATIMER BROOK NR I-95N EXIT 75 NR FLANDERS, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=011277905
LITTLE RIVER NEAR HANOVER, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01123000
MILL RIVER NEAR FAIRFIELD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01208925
MILL RIVER NEAR HAMDEN, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01196620
MOUNT HOPE RIVER NEAR WARRENVILLE, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01121000
MUDDY RIVER NEAR EAST WALLINGFORD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01196561
NATCHAUG RIVER AT WILLIMANTIC, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01122000
NAUGATUCK RIVER AT BEACON FALLS, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01208500
NAUGATUCK RIVER AT THOMASTON, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01206900
NONEWAUG RIVER AT MINORTOWN, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01203600
NORTH BRANCH PARK RIVER AT HARTFORD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01191000
NORWALK RIVER AT SOUTH WILTON, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01209700
POMPERAUG RIVER AT SOUTHBURY, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01204000
POOTATUCK RIVER AT BERKSHIRE https://waterdata.usgs.gov/ct/nwis/uv?site_no=012035055
POOTATUCK RIVER AT SANDY HOOK, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01203510
QUINEBAUG RIVER AT JEWETT CITY, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01127000
QUINEBAUG RIVER AT PUTNAM, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01125500
QUINEBAUG RIVER AT QUINEBAUG, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01124000
QUINNIPIAC RIVER AT SOUTHINGTON, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01195490
QUINNIPIAC RIVER AT WALLINGFORD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01196500
RIDGEFIELD BROOK AT SHIELDS LANE NR RIDGEFIELD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=012095493
RIPPOWAM RIVER AT STAMFORD, CT. https://waterdata.usgs.gov/ct/nwis/uv?site_no=01209901
ROOSTER RIVER AT FAIRFIELD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01208873
SALMON RIVER NEAR EAST HAMPTON, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01193500
SASCO BROOK NEAR SOUTHPORT, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01208950
SAUGATUCK R BELOW SAUGATUCK RES NR LYONS PLAIN, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01209005
SAUGATUCK RIVER NEAR REDDING, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01208990
SAUGATUCK RIVER NEAR WESTPORT, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01209500
SHETUCKET RIVER AT TAFTVILLE, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=011230695
SHETUCKET RIVER NEAR WILLIMANTIC, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01122500
STILL RIVER AT ROUTE 7 AT BROOKFIELD CENTER, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01201487
STONY BROOK NEAR WEST SUFFIELD, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01184100
WEEKEEPEEMEE RIVER AT HOTCHKISSVILLE, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01203805
WILLIMANTIC RIVER NEAR COVENTRY, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01119500
YANTIC RIVER AT YANTIC, CT https://waterdata.usgs.gov/ct/nwis/uv?site_no=01127500
site_no24

*We are defining low flow as below the 25th percentile for that stream, OR below 25% of the mean OR below 25% of the median flow for that stream for the date. Data source: https://waterwatch.usgs.gov/webservices/realtime?region=ct&format=xml on Thu March 9, 2017. Click here for a list of all CT stream gages comparing their flow right now to their mean and median flows for today's date.

Streamflow Graphs and Storms

Click to enlarge. Streamflow graphics courtesy USGSAs the graphic to the right illustrates, where a storm moves across the state, the streams show flows that peak above their averages for this time of year but then quickly drop. The streams that maintain healthy flows between storms are those draining the parts of the state where there has been decent rainfall or those controlled by managed dams.

How quickly the flow drops after each rainstorm is unique for each stream, because it depends on how much water soaked in to increase the groundwater baseflow. In watersheds with lots of impervious roads, roofs, parking lots, patios, and compacted soil in lawns, a lot of the rain typically flows over the surface or through storm drains directly into the streams, leading to flooding problems far more often than in watersheds with mostly natural surfaces. Their streamflow then drops quickly after the storm ends, and the flow levels off far lower than in streams whose watersheds have more natural surfaces.

The U.S. Drought Monitor publishes a weekly analysis of drought conditions across the entire nation based on a variety of types of data that include streamflow. The report comes out every Thursday based on data from that Tuesday. The U.S. Drought Monitor is produced by the National Drought Mitigation Center, which is also on Facebook.

Their regional narrative for the Northeast on Mar 23 explains why 42% of the state is still rated Severe, and 46% Moderate Drought: "... although [Northeast] conditions have been favorably wet over the past 90 days, lingering Moderate and Severe Drought areas (D1 and D2) have reported below-normal precipitation over the same time frame. Furthermore, these same locales are still exhibiting pronounced long-term deficits, with 12-month precipitation averaging 60 to 80 percent of normal. While streamflows have rebounded, slower-to-recover groundwater levels remained much lower than average. Despite the recent rain and snow — which alleviated the short-term (“S”) component of the drought — long-term drought (“L” on the map) remained in areas where significant long-term deficits persisted."

Since the end of January Connecticut has had the dubious distinction of being the most drought-afflicted state of all 50 based on percentage of area, but Oklahoma is now a close second. Other states still have areas of Extreme Drought, and Oklahoma has a higher percentage of area rated Severe or above, we still have the greatest percentage of area rated Moderate Drought and above. By adding the percentages of each state in each category, an index or relative drought affliction can be calculated. The following table lists the most afflicted states in order by this index.

What Are the Most Drought Afflicted States?
March 23, 2017

       



 
Source: http://droughtmonitor.unl.edu/Home.aspx
State % No Drought % Abnormally Dry or Worse
Sq Miles % Moderate Drought or Worse
Sq. Miles % Severe Drought or Worse
Sq. Miles % Extreme Drought Sq. Miles Percentage Comparative Value (sum of %) Sq Miles Comparative Value (sum of sq miles)
 Connecticut 0 100 5543 88 4892 42 2339 0 0 230 12774
 Oklahoma 7 93 64859 81 56311 46 32181 3 2216 223 155567
 Missouri 4 96 66793 79 55187 8 5904 0 0 183 127884
 Massachusetts 1 99 10413 67 7049 15 1555 0 0 180 19017
 Kansas 3 97 79810 48 39387 9 7413 1 469 154 127079
 New Hampshire 23 78 7267 59 5553 10 939 0 0 147 13759
 South Carolina 11 89 28655 36 11386 18 5639 4 1332 147 47012
 Arkansas 14 86 45633 40 21314 18 9753 2 1064 146 77763
 Alabama 29 71 37197 41 21529 22 11475 2 865 136 71066
 Florida 20 80 52803 44 28966 5 3505 0 0 130 85275
 North Carolina 34 66 35720 39 20887 15 8024 5 2551 125 67182
 Georgia 39 62 36546 27 15979 19 11338 7 4124 114 67988
 Louisiana 16 84 44097 19 9868 0 0 0 0 103 53965
 Virginia 41 59 25040 41 17516 2 941 0 0 102 43498
 Colorado 48 52 54077 42 43532 5 5350 0 208 99 103167
 Tennessee 25 75 31440 13 5630 5 1998 1 476 94 39544
 Mississippi 35 65 31602 17 8185 3 1632 0 0 86 41419
 Maryland 55 45 5554 29 3583 3 356 0 0 77 9493
 New Jersey 59 41 3611 10 857 0 0 0 0 51 4468
 California 77 23 38403 8 13488 1 1735 0 0 33 53626


As the below graph shows, Connecticut has been labeled Abnormally Dry, Moderate Drought, or worse pretty often over the last few years. This graph was made before any of the state was rated as Extreme.

How does the current drought compare to historic droughts in Connecticut? The graph to the right is from NOAA's National Environmental Satellite, Data, and Information Service (NESDIS), displaying the Palmer Hydrologic Drought Index (PHDI) for our state for the past century (click on it for a larger view in a new tab). If groundwater and streamflow did not fully recover from the annual return of drought conditions of the past few years, we can consider our current drought as starting in 2010 or 2012. The overall length of time we have had these intermittent drought conditions is becoming comparable to the continuous drought of the 1960s. The severity of the current drought is approaching the average severity of the 1960s. It is therefore fair to say the current drought is one of the worst in 100 years. Area weather forcasters have been reporting that the current drought is the worst since the 1960s.  

 

Dire situation in 2015 ...

For a good analysis of last year's stream problems across the state, see this press release from Pomperaug River Watershed Coalition (PRWC). Here is a key quote:

The September and October low river flows demonstrate that rivers were not supporting the critical flows needed for a healthy river habitat. In fact, sections of the Weekeepeemee River had dry river beds and the Pomperaug River was flowing only at a rate of 15% of the critical flow requirement. DEEP officials confirmed that they would expect fish mortality to increase significantly during such conditions...
Click to enlarge

Photo from PRWC.

Meanwhile, parts of Coppermine Brook in Bristol were drawn down to rocks and dirt, as shown in the photo below taken Dec. 11, 2015, in Bristol. The sandy ditch in the foreground is the stream channel. Bristol Water Company and New Britain Water Company have eight registered diversions near Coppermine or its tributaries with a combined registered water withdrawal of 36.6 million gallons per day (source: CT DEEP). Company representatives report they do not withraw anywhere near that much water. Bristol Water says they stopped pumping from their well near this photo for a day but with no apparent effect on the stream. This is a perennial stream with a state Trout Management Area below where this picture was taken. Click on the photo for a full-screen version in a new tab.

Coppermine Brook, Bristol CT. Friday,
          Dec 11, 2015.
Coppermine Brook, Bristol CT, Friday, Dec. 11, 2015; photo by Tony Mitchell

 

This graph plots the rate of flow on September 4, 2015 as a percentage of the median for each stream gage. For example, a dot at the 40% line means that stream that day was flowing at 40% of what could be considered normal for that date. The few rivers and streams flowing at or above 100% of their median rate are mostly those with flows managed by dam releases.

Click here for a search of news articles about the drought

Some archived Know Your Flow pages
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20170316.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20170221.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20170206.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20170127.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20170119.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20170113.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161215.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161208.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161201.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161125.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161122.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161121.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161117.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161102.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161027.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161020.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161013.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20161006.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20160919.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20160915.htm
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20160901.htm
http://www.riversalliance.org/drought/droughtarchive/droughtbefore20160822.htm#lowest
http://www.riversalliance.org/drought/droughtarchive/droughtbefore20160811.htm#lowest
http://www.riversalliance.org/drought/droughtarchive/droughtbefore20160804.htm#lowest
http://www.riversalliance.org/drought/droughtarchive/droughtbefore20160822.htm#lowest
http://www.riversalliance.org/drought/droughtarchive/droughtbefore20160317.htm#lowest

2015
http://www.riversalliance.org/drought/droughtarchive/droughtbefore20151228.htm#lowest 
http://www.riversalliance.org/drought/droughtarchive/droughtbefore20150925.htm#lowest
http://www.riversalliance.org/drought/droughtarchive/droughtbefore20150921.htm#lowest
http://www.riversalliance.org/drought/droughtarchive.cfm?filename=droughtbefore20150925.htm http://www.riversalliance.org/drought/droughtarchive/droughtbefore20150903.htm  http://www.riversalliance.org/drought/droughtarchive/droughtbefore20160316.htm 

 

NASA's climate monitoring programs to be axed?

Rivers Alliance of Connecticut
PO Box 1797, 7 West Street 3rd Floor, Litchfield, CT 06759-1797
860-361-9349
rivers@riversalliance.org, www.riversalliance.org