Stormwater retention ponds may not protect surface waters from road salt contamination.
Stormwater management practices are designed to intercept water runoff from roads and parking lots before pollutants reach surface waters.
Detaining runoff in retention ponds can reduce flooding, increase the amount of water that is absorbed into the ground, and allow pollutants to bind to sediments in the ponds or be absorbed by algae and plants instead of traveling to streams and wetlands where they may harm wildlife and human health.
The research team recently completed a study, published in Environmental Science and Technology, to determine how well current stormwater management practices mitigate the effects of road salts and how those salts might be impacting both the surface waters in streams and ponds, and the groundwater that many citizens using well systems rely on daily.
If the stormwater ponds were working effectively, Snodgrass explained, he and his team could test the groundwater between the ponds and streams and expect to find very little sodium chloride because it would have been retained in the ponds.
The researchers discovered that routing runoff contaminated with road salts to stormwater ponds actually resulted in plumes of highly contaminated groundwater moving from the ponds to streams.
If salt levels continue to increase in freshwater areas, many fish and amphibians will stop breeding and eventually die because their bodies cannot adjust to the change.
"Some counties are already reimbursing people for the costs associated with replacing contaminated water wells," he added.
Snodgrass and his team plan to continue researching how road salts and other chemicals affect wildlife and the environment, while other researchers are exploring the effectiveness of alternatives to road salts and their potential effects on the environment and human health.
"It’s a balance sheet we’re looking at between economics and the environment and human health," Snodgrass said.

Drought already searing northeast Montana.
Drought conditions in northeast Montana have developed rapidly since the end of April.
Despite two consecutive years of record precipitation in 2015 and 2016, the winter months of 2017 did not bring much moisture; and while precipitation totals for April were average, May has seen only 25 percent of normal precipitation, along with above-normal temperatures.
Rainfall is critical at this time of year for dryland producers across the region.
“This one took us by surprise,” said Ada Montague, a water planner with the Montana Department of Natural Resources and Conservation.
“While Wibaux and Fallon counties were on our radar, we did not anticipate such dry conditions would develop so quickly across such a large area.” While subsoil moisture is holding steady at normal, Montague said topsoil conditions to about 8 inches below the surface are below average.
Montague said the Governor’s Drought and Water Supply Advisory Committee members have received reports that producers are selling off cattle due to concern about available forage in Dawson, Richland, McCone, Roosevelt, Prairie, Wibaux and Fallon counties.
Reports of dry conditions are also coming in from Valley and Sheridan counties.
“We have made reports to the U.S. Drought Monitor of the impacts to ag producers in northeast Montana,” Montague said.
“We continue to monitor conditions, and we’re also working with the Montana Department of Agriculture and the Montana Department of Emergency Services to make sure we are doing all we can to address producer concerns.” Montague said it’s important that producers contact their local Farm Service Agency office to report any losses.

Signs of drought crop up across Northeast Montana.
Drought conditions in Northeast Montana have developed rapidly since the end of April.
Despite two consecutive years of record precipitation in 2015 and 2016, the winter months of 2017 did not bring much moisture; and while precipitation totals for April were average, May has seen only 25 percent of normal precipitation, along with above-normal temperatures.
Rainfall is critical at this time of year for dryland producers across the region.
“This one took us by surprise,” said Ada Montague, staff person for the Governor’s Drought and Water Supply Advisory Committee (DWSAC) and a water planner with the Montana Department of Natural Resources and Conservation.
“While Wibaux and Fallon counties were on our radar, we did not anticipate such dry conditions would develop so quickly across such a large area.” While subsoil moisture is holding steady at normal, Montague said topsoil conditions to about eight inches below the surface are below average.
Wind and above-normal temperatures have played a major role in depleting surface moisture, she noted.
Reports of dry conditions are also coming in from Valley and Sheridan counties.
“We have made reports to the US Drought Monitor of the impacts to ag producers in Northeast Montana,” said Montague.
The next Governor’s Drought and Water Supply Advisory Committee meeting will be held on June 20, 2017, from 9-11 am at DNRC Headquarters in Helena.

The Water Year’s Long, Cold, and Wet Goodbye Kiss to the Northwest’s Drought.
For the first time since 2011, the Pacific Northwest is not registering any sign of drought on the U.S. Drought Monitor.
Here’s what we know: The water year starts every calendar year on Oct. 1 (ending on Sept. 30 of the following calendar year).
This water year, the normally drier months of October, February, March and April were wetter than normal — much wetter — across the entire Pacific Northwest.
Unfortunately, heavy precipitation that early in the water year didn’t end the drought — that would come later — and it arguably did more harm than good.
However, most of this October’s precipitation fell as rain, not as snow that can accumulate in the mountains and then melt and run off later in the year.
Like rain in October, snow in December and January is not uncommon.
Whereas many of the drought years, especially 2015, were especially warm, this winter was especially cold.
In fact, this winter was the coldest winter on record in the Pacific Northwest since 1992-93.
So what was different about this year?

2017 South America winter forecast: Drought to worry Colombia, Venezuela; Frequent storms to strike Chile, Argentina.
Meanwhile, warm waters in the Pacific Ocean will help to spread rain across much of the western countries of South America.
Argentina to face more rain, mountain snow than last winter Rounds of rain will frequent Argentina this winter as storm systems move across the country on a regular basis.
“More storms are expected across central Argentina this year versus last year with near- to slightly above-normal rainfall in cities such as Buenos Aires,” AccuWeather Lead International Meteorologist Jason Nicholls said.
Drought concerns to return to Colombia, Venezuela Drought has plagued Colombia and Venezuela in recent years, and this winter will bring little relief to the countries.
“Drought concerns will return along the Caribbean coast of the continent from northern Colombia and Venezuela to French Guiana,” Nicholls said.
Warm waters off the coast of Brazil may keep drought conditions from returning to far northeastern Brazil, Nicholls said.
While winter is not typically a wet time of year, drought conditions could develop in the Brazilian states of São Paulo to Minas Gerias, Nicholls said.
Wet winter on tap from Chile to Peru Frequent storms will bring rounds of rain and mountain snow to Chile this winter with the tracks of the storms shifting as the season progresses.
“The warm waters over the Pacific Ocean will lead to wetter-than-normal conditions from Ecuador and Peru into Bolivia,” Nicholls said.

Forecasters at NOAA’s Climate Prediction Center issued the U.S. Winter Outlook today, saying that La Nina is expected to influence winter conditions this year.
La Nina favors drier, warmer winters in the southern U.S and wetter, cooler conditions in the northern U.S.
"This climate outlook provides the most likely outcome for the upcoming winter season, but it also provides the public with a good reminder that winter is just up ahead and it’s a good time to prepare for typical winter hazards, such as extreme cold and snowstorms," said Mike Halpert, deputy director, NOAA’s Climate Prediction Center.
"Regardless of the outlook, there is always some chance for extreme winter weather, so prepare now for what might come later this winter."
Other factors that often play a role in the winter weather include the Arctic Oscillation, which influences the number of arctic air masses that penetrate into the South and create nor’easters on the East Coast, and the Madden-Julian Oscillation, which can affect the number of heavy rain events in the Pacific Northwest.
The 2016 U.S. Winter Outlook (December through February): Precipitation Wetter than normal conditions are most likely in the northern Rockies, around the Great Lakes, in Hawaii and in western Alaska Drier than normal conditions are most likely across the entire southern U.S. and southern Alaska.
Temperature Warmer than normal conditions are most likely across the southern U.S., extending northward through the central Rockies, in Hawaii, in western and northern Alaska and in northern New England.
Cooler conditions are most likely across the northern tier from Montana to western Michigan.
Drought improvement is anticipated in northern California, the northern Rockies, the northern Plains and parts of the Ohio Valley.
Snow forecasts are dependent upon the strength and track of winter storms, which are generally not predictable more than a week in advance.

Washington, neighbors all drought-free after wet winter.
Looking for a silver lining after Seattle’s gray, rainy winter?
After a historically wet few months, there are currently no drought warnings for the Evergreen state.
Brian Fuchs of the National Drought Mitigation Center said the improvement in the region’s drought conditions began last year, when a strong El Niño pattern unexpectedly impacted areas further north than usual.
This year’s rainy weather led to more steady improvement.
That’s nearly 50 percent more precipitation than the yearly average of just over 30 inches over the same time period and about a half-inch more than the previous October through April.
Showers are expected on and off throughout the weekend, with the best chance of accumulation coming on Saturday and Monday.
Established in 199, the U.S. Drought Monitor is a weekly map of drought conditions produced jointly by the National Oceanic and Atmospheric Administration, the U.S. Department of Agriculture, and the National Drought Mitigation Center at the University of Nebraska-Lincoln.
Seattlepi.com reporter Stephen Cohen can be reached at 206-448-8313 or stephencohen@seattlepi.com.
Follow Stephen on Twitter at @scohenPI.

A drama is presently unfolding in the coastal city of Cape Town, South Africa, and maritime technology could offer a solution here and in other cities around the world.
Maritime Water Tankers During such times, converted tanker ships could carry potable water from a region of generous rainfall to a drought-stricken region.
Airborne kite sails are one of the technologies being used to assist in providing ship propulsion along routes where trade winds blow parallel to sailing direction.
A desalination ship could include both reverse-osmosis-membrane technology as well as thermal desalination technology to provide potable water.
Either a short-distance water pipeline would connect the desalination ship to the shore, or a water tanker ship would shuttle potable water from offshore desalination ship to shore-based water tanks.
Wind energy ships could use rotary turbines or airborne sails to directly drive water pumps that could produce sufficient pressure to sustain operation of reverse-osmosis desalination technology.
Small-scale, ship-based nuclear power could also provide energy for seawater desalination.
Modern day drought reduces hydroelectric power generation.
During modern drought periods, maritime based technology can achieve much in terms of providing temporary relief to drought-stricken coastal regions.
Maritime based technology can provide electric power and potable water on a seasonal basis to many locations around the world, thereby making such technology viable.

Comments (2) There are fears Cornwall could be on course for drought following one of the driest winters on record and with reservoir levels lower than the last year one was declared.
According to figures published by South West Water, the two of the three reservoirs for Cornwall, Colliford and Roadford, are down to 84% and 75% full respectively.
Stithians is fairing better at 95% full, but overall the five main reservoirs for the Westcountry are at around 85% capacity while the same week last year was at 96% capacity.
South West Water said levels were not unusual for the time of year and the company was "well placed" to cope with lower rainfall and higher demand expected in the summer.
However, the Met Office has this week revealed that it was the third driest winter on record and long range forecasts say the mild, dry weather is set to continue.
Read more: Minister promises A30 improvements, but won’t say when A spokesman for the National Farmers Union in the South West said it was monitoring the situation.
A 30-day forecast by the Met Office suggests that there will be mainly dry settled conditions with some warm temperatures developing this month.
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Read more: Why Cornwall Live was banned from filming the Prime Minister’s visit to a Helston factory Stithians is below the level of last year, but above that of the 1995 drought year.
She said: "Current reservoir levels are not unusual for the time of year but reflect the dry weather we have experienced over the last six months.

Record low drought since monitoring began 17 years ago.
Thursday, May 4, 2017, 3:30 – Since drought monitoring began back in January of 2000, current values as of May 2, 2017 are the lowest in these 17 years and 5 months of recorded data.
One year ago, 33.89 percent of the contiguous US was experiencing some type of drought, with 14.56 percent in the moderate to exceptional drought category and 2.33 in an extreme drought alone.
Today extreme drought affects only 0.13 percent of the countries surface and there is no exceptional drought in sight.
The most remarkable changes in the drought monitor values are those recorded in the west.
There are no longer signs of extreme or exceptional drought conditions, and only 2.72 percent exhibits a moderate to severe drought situation.
A favorable weather pattern with a record breaking number of Atmospheric Rivers during the 2016-17 winter months also delivered plenty of moisture into the western third of the US helping erase a large swath of drought values across many areas.
An active jet stream has been driving storms across portions of the Central Plains and the Tennessee River Valley, areas which have been affected by moderate to extreme drought conditions throughout much of the Winter and Spring months.
Two weeks ago 44.63 percent of the southeast region was experiencing drought, today that value has been cut down to 34.35.
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