Dillon source water is leaching lead from fixtures and supply lines, town awaits state approval for methods to raise pH

Dillon townsite prior to construction of Dillon Reservoir via Denver Water

From The Summit Daily (Sawyer D’Argonne):

During recent testing mandated by the Colorado Department of Public Health and Environment at 20 different sites earlier this year, the town discovered that seven had lead levels in excess of the state’s maximum allowable limit of 15 parts per billion. The finding comes just months after Frisco discovered a similar issue in their sampling pool.

Dillon officials stress that the town has good, clean surface water.

“We don’t have lead in our source water,” said Scott O’Brien, Dillon’s public works director. “We’ve monitored for that, and it’s not the issue. … The issue is the materials that were used prior to 1987 for constructing homes, copper pipe with leaded solder. In addition to that, a lot of fixtures like faucets were constructed with either brass or bronze — metal alloys that contain lead.”

O’Brien said that because the source water is so “aggressive,” it’s leeching the lead out of older pipes and fixtures at testing sites, resulting in the elevated rates. In determining aggressiveness, the town looks at four main factors: pH levels, alkalinity, temperature and hardness.

The pH level in the water measures how acidic or basic the water is on a scale of 0 to 14 — anything below 7 is considered acidic, and anything higher is considered basic. In general, high acidity means the water is more corrosive, and more likely to leech metal ions like lead and copper. Dillon’s source water is naturally about 7.3, or slightly leaning towards the basic side.

Alkalinity is a measure of the buffering ability of the water, essentially the ratio of hydrogen ions versus hydroxide ions that determines the water’s ability to neutralize acid. O’Brien noted that Dillon’s water has low alkalinity. Temperature is self-explanatory, literally describing how hot or cold the water is — wherein hotter water is more reactive and aggressive than cold water. Hardness measures the mineral concentration in the water, or what it’s naturally picking up as it flows along. Because Dillon uses its source water so quickly, it is relatively soft.

“We’re the first in line to pick it up, and it doesn’t have the chance to pick up these other minerals and other things that help reduce the aggressiveness of the water,” said O’Brien.

This is a problem that Dillon has dealt with in the past. The town’s testing also returned high lead levels in both 2012 and 2014, and officials have been working with the state since to address the issue. In 2014, the town attempted to adjust the pH levels up to about 8.5 on the scale, which appeared to have worked over the last five years. Though, due to recent changes in regulations from the state level — which essentially requires towns to zero in on high-risk testing sites to determine the worst-case scenarios for water quality issues — new issues are being discovered.

“To get a representative sample pool they don’t want us to go over the distribution system geographically, and sample it spread out,” said Mark Helman, chief water plant operator. “They want us to sample these particular sites built from 1983 to 1987 (before the Lead Contamination Control Act in 1988) they know are going to give us the worst results. … This is a process of us learning where the worst sites are that we have, testing those sites, seeing how our water is doing at those sites, and if we have a problem we want to address the worst case scenario.”

Both O’Brien and Helman noted that they already have a plan to try and address the issue of overly aggressive water. The plan is to add soda ash — sodium carbonate or baking soda — during the water treatment process to increase pH levels, alkalinity and hardness to the water to reduce aggressiveness. However, because it includes changes to the plant, the new process must first be signed off on by the state.

O’Brien said that once the state approves the town’s new water treatment methods they’ll be able to implement the new process quickly, though the review process could take between 30 and 60 days.

Transmountain water boosts dilution of mine drainage and benefits gamefish in the North Fork of the #SouthPlatte #ColoradoRiver #COriver

From The Fairplay Flume (Kelly Kirkpatrick):

Why, exactly, are the fish dying?

Fish kills in the North Fork of the South Platte River are occurring during low water flow periods that fail to dilute the toxicity of heavy metals such as iron, copper and aluminum. Contaminants in the form of heavy metals move downstream, originating primarily from Hall Valley and Geneva Creek mining operations.

When water flow is adequate, there is enough oxygen to negate the impact of the toxins. When water levels are inadequate, fish develop coatings on their gills as a natural self-defense mechanism to the toxins. That protective coating ultimately renders their gills inoperable.

When and why do water levels get too low?

Water flow in the river is dependent upon how much water is released from Dillon Reservoir through Roberts Tunnel, and those decisions are made almost exclusively by Denver Water.

When more water is needed within Denver Water service areas, the rate of the water passing through Roberts Tunnel is set to flow more freely. When water is not needed to serve the Denver Water service area, the flow from Roberts Tunnel is restricted, much to the detriment of the people, and the fish, in Park County.

Water flows can be naturally low in the river during certain seasons. This year, in mid-March, for example, snowmelt had not yet occurred and the river was in its customary state of low flow prior to the fast-approaching late-spring thaw.

An abundance of area-wide spring moisture, however, created a situation where Denver Water service areas enjoyed a surplus of water. Therefore, the flow from Roberts Tunnel and Dillon Reservoir was ceased on March 11 and remained so at least until this writing.

The predictable result was the most recent fish kill, which occurred March 11-15, because flows were simply not sufficient to combat ever-present toxic heavy metals related to mining. No information has been provided by Denver Water as to when the tunnel will be reopened.

Denver Water states its position

When The Flume recently requested a statement from Denver Water regarding flows in the river and operations of Roberts Tunnel, a response was received in timely fashion.

In direct response to whether or not Denver Water felt a moral obligation to residents in Park County related to ecological systems they have long controlled, and whether Denver Water should accept responsibility for maintaining minimal flow in the South Platte River for the environmental and economical benefit of the entire North Fork region, the following statement was submitted:

“We (Denver Water) understand the potential for impacts to the fishery when flows from the Roberts Tunnel are shut down, and certainly recognize and appreciate the effect on the angling community and local businesses and outfitters. Unfortunately, operation of the Roberts Tunnel is directed by legal obligations and decrees tied to Colorado water law and binding agreements with West Slope communities where the water from the tunnel originates.

“As you know, the flows from the Roberts Tunnel originate in water diverted from West Slope rivers and streams into Dillon Reservoir. Denver Water depends on this supply when snow pack within the Upper South Platte watershed is insufficient. However, since early March, portions of the Upper South Platte watershed have received more than four feet of snow and spring precipitation continues to be strong.

“Legally, water supplied through the Roberts Tunnel can only be accessed when water is needed in Denver Water’s service area. Further, any other uses for the water, including augmenting stream flows for aquatic life or recreation uses, are not allowed as a primary purpose for operating the tunnel.

“While we provide projections about how long Denver Water will deliver water through the tunnel, those are only estimates based on snow pack, reservoir storage and other system elements. Those projections can change as conditions change; as they did in late winter and early spring this year.”

Colorado transmountain diversions via the State Engineer’s office

The #BlueRiver through Breckenridge is clearing up

Colorado abandoned mines

From The Denver Channel (Russell Haythorn):

Experts say the discoloration came from heavy rains on Friday, causing mine waste and mud from a beaver dam upstream to break free.

Red White and Blue fire chief Jim Keating says tests show there was never any hazard to public health or to the wildlife.

“What we’re seeing here is honestly, mostly mud,” Keating said. “Red mud.”

The discoloration was certainly concerning.

“It had a lot of people freaked out,” Keating said. “Particularly – I think – the most calls I got were people who fish the area.”

By Monday things had mostly cleared up…

With snowpack well above average and more snow and rain in the forecast this week, experts say this could be a common theme this mud season.

“While we are vigilant, we’re not terribly concerned right now,” Keating said.

Acid mine drainage turns the #BlueRiver orangish at Breckenridge

From The Summit Daily (Deepan Dutta):

The Blue River turned orange in Breckenridge on Saturday afternoon. The river’s water went from its natural blue-green hue to a bright, burnt orange within a few hours, with emergency officials believing the discoloration to be runoff from an area above Illinois Gulch known to cause similar discoloration in the past.

After investigating, fire officials determined that the runoff came from a mine located on private property at the corner of Boreas Pass Road and Bright Hope Circle. The water runoff at the source appeared as a thick, muddy orange stream with no obvious unique odor or taste. Fire officials said that the location has been the source of orange mine runoffs in the past…

Red, White and Blue Fire District issued a press release Saturday evening stating that first responders were alerted about discolored water in the Blue River at 3:15 p.m. Multiple fire companies and a specialty HAZMAT unit responded. The fire district determined that the source of the orange water was a known release point on Boreas Pass Road. Initial testing done by fire district personnel found the water to not be an immediate danger to human health. The fire district also said there is no immediate corrective action possible from first responders. Typically, this kind of orange mine runoff lasts about 24 hours.

“Given the rainfall that occurred last night, it is not surprising that we are seeing this type of activity today,” said RWB batallion chief and incident commander Drew Hoehn. “We realize the optics of the run-off are in stark contrast to what folks are normally used to seeing in the Blue River, but we are confident in the assessment and assurance of the public’s welfare in this particular situation.”

Summit County’s director of environmental health, Dan Hendershott, also sought to downplay concerns about the health impact of the orange water.

“Based on previous similar releases that have occurred, we don’t have reason to believe this event poses a risk to the public’s health,” Hendershott said. “However, out of an abundance of caution, we recommend that people and pets avoid contact with this water. Untreated surface water should never be consumed, and that would certainly be the case here, too.”

Authorities are still investigating the incident and all local water districts have been notified. The Blue River is one of the primary sources for the Dillon Reservoir, which provides drinking water for hundreds of thousands of people on the Front Range.

Prior to mining, snowmelt and rain seep into natural cracks and fractures, eventually emerging as a freshwater spring (usually). Graphic credit: Jonathan Thompson

Colorado’s Lake Dillon is Warming Rapidly — @CIRES

Grays and Torreys, Dillon Reservoir. Photo credit Greg Hobbs.

From CIRES:

CU Boulder researchers harness 35 years of data to uncover responses of a high-elevation reservoir to a warming world

The surface waters of Lake Dillon, a mountain reservoir that supplies water to the the Denver area, have warmed by nearly 5 degrees Fahrenheit (2.5 degrees Celsius) in the last 35 years, which is twice the average warming rate for global lakes. Yet surprisingly, Dillon does not show adverse environmental changes, such as nuisance algal blooms, often associated with warming of lakes. Researchers at the CIRES Center for Limnology, who have just published a multi-decadal study of Lake Dillon, conclude that the lake’s rapid warming and its lack of ecological response to warming are explained by the high elevation of the lake.

“The warming of Lake Dillon is a result of climate change but, in contrast with warm lakes, which respond in undesirable ways to warming, Lake Dillon shows no environmental response to warming, said William Lewis, Director of the CIRES Center for Limnology and lead author of the new paper published today in AGU’s Water Resources Research. “The explanation for the lake’s ecological stability lies in its low temperature, which serves as a buffer against ecological effects of warming.”

Since 1981, Lewis and colleagues in the CIRES Center for Limnology have collected detailed information not only on Lake Dillon’s temperature, but also on its water quality and aquatic life. Full vertical profiles of water temperature document changes in vertical distribution of heat over time. The record shows that warming of tributary water contributes to warming of the lake’s deepest waters.

“The 35-year data set allows us to see the complete warming pattern of the lake,” said James McCutchan, associate director of the Center. Natural events, including droughts and floods, create interannual variation that obscures the effects of climate change over short intervals, whereas multidecadal data sets can show more clearly the effects of climatic warming.

Dillon is the highest lake yet studied for full water column warming, as Lewis and his colleagues note in their paper. The study also is the first to analyze warming in a reservoir, rather than a natural lake.

“Reservoirs can differ fundamentally from other lakes in their response to warming because they often release water from the bottom as well as the top of the water column,” said Lewis. “They can warm not only from the top, in response to solar radiation reaching the surface, but also from the bottom, as tributaries subject to climatic warming replace cold bottom water with progressively warmer tributary water.”

The Lake Dillon study program is sponsored by Denver Water, which uses the water for treatment and delivery to Denver residents, and by the Summit Water Quality Committee, which represents the interests of local residents in preservation of Lake Dillon’s water quality.

Summit County is crafting their #climateactionplan building on the foundation of a thorough #greenhousegas inventory #ActOnClimate

Click here read their climate Action Plan.

Water year 2018 closes as one of driest on record for upper #ColoradoRiver Basin — @AspenJournalism #COriver #aridification

Drying in process on the Colorado River, where Lake Powell once stood, in early October 2018. Photo credit: Aspen Journalism/Brent Gardner-Smith

From Aspen Journalism (Heather Sackett):

Colorado water managers are saying good riddance to water year 2018. It enters the history books alongside 2002 and 1977 as one of the driest on record for the Upper Colorado River Basin.

According to preliminary numbers from the Bureau of Reclamation, water year 2018, which ended Sept. 30, had the third-lowest unregulated inflow into Lake Powell at 4.62 million acre-feet. That’s just 43 percent of average.

Only 1977 and 2002 saw less water flow into Lake Powell from the upper basin, at 3.53 million acre-feet and 2.64 million acre-feet, respectively.

The average yearly inflow is 10.8 million acre-feet.

The months of August and September 2018 were the third- and fourth-worst months for unregulated inflows into Lake Powell behind only July and August of 2002.

The unregulated flow in August was just 2 percent of average. Lake Powell is currently 46 percent full.

“We know if we have another drought, the risk of draining Lake Powell is real,” said Jim Pokrandt, director of community affairs for the Colorado River Water Conservation District and chairman of the Colorado Basin Roundtable. “If we have another year as bad as this one, you’re going to see lots of discussions about who’s going to take reductions. We really need three, four, several years of average or above-average snow years to get us out of this pickle.”

Low flows in the Roaring Fork River just above Rio Grande Park, in July 2012. Water year 2018 surpassed 2012 as third driest in terms of inflow into Lake Powell from the Upper Colorado River Basin. Photo credit: Aspen Journalism/Brent Gardner-Smith

Roaring Fork conditions

Locally, the Roaring Fork watershed was extremely dry this water year. The region was plagued by record-low snowpack — the lowest snow-water equivalent ever recorded for some dates at the McClure Pass and Independence Pass SNOTEL sites — sparse runoff, record-low streamflows and a hot, dry summer.

Low flows were prevalent across Colorado during the last two weeks of the water year, which runs from October through September. According to the National Oceanic and Atmospheric Administration’s drought information system, 30 percent of U.S. Geological Survey stream gauges in the intermountain West reported record-low seven-day-average stream flows for the last two weeks of September, including some in the Roaring Fork watershed.

On Sunday, the last day of the water year, the USGS river gauge on the Roaring Fork at Stillwater Road just east of Aspen showed the river flowing at 19 cubic feet per second, beating the previous minimum flow of 21 cfs in 1977.

Flows on the Crystal River were similarly low. Above Avalanche Creek and above a series of diversion structures, the river was running at nearly 46 cfs, lower than the previous record low of 48 cfs in 1977.

At the river gauge near the state fish hatchery and downstream from several diversion structures just outside of Carbondale, flows dribbled down at just under 7 cfs Sunday.

Colorado Department of Water Resources Engineer for Division 5 Alan Martellaro said the summer’s weak monsoons exacerbated conditions caused by little snowfall.

“We had a bad snowpack,” Martellaro said. “It was not the worst, but then we have had an incredibly dry summer, a total lack of rain. I think when we start analyzing it, we are going to find the flows in late summer are unprecedented. We have done some things we have never done before.”

Martellaro is referring to curtailment on the lower Crystal in late July. Amid rapidly dropping flows, the district 38 water commissioner turned down the headgate of the Lowline Ditch, which he determined was diverting too much water. The ditch diversion did not exceed its legally decreed amount; the problem was that it was violating new state guidelines regarding wasting water.

According to data from the Natural Resources Conservation Service, many sites around western Colorado rank as the driest since recording began for water-year precipitation, including McClure Pass, Schofield Pass and Independence Pass.

Statewide, the water year precipitation average at all SNOTEL sites measured just 21.4 inches, which is 64 percent of average — the second-lowest on record behind only 2002.

“It was pretty consistently dry throughout the entire year,” said Karl Wetlaufer, a hydrologist with the NRCS Colorado Snow Survey. “February may have been the only month where we had near-normal precipitation across the state.”

Paonia Reservoir was at 7 percent full at the end of September. Water year 2018 ranked as the third driest in the Colorado River Basin. Photo credit: Heather Sackett/Aspen Journalism

Reservoirs low

In some instances, reservoir releases have come to the rescue of downstream anglers, fish and ecosystems.

Releases from Ruedi Reservoir will continue through October to bolster flows for endangered fish in what’s known as the 15-mile reach, a notoriously dry section of the Colorado River between the Palisade area and the confluence with the Gunnison River in Grand Junction.

[Reclamation has been releasing water from] Ruedi Reservoir.

Periodic releases from Green Mountain Reservoir near Kremmling also boosted summer flows in the Colorado River. But that water will need to be replaced this winter by snowfall, Martellaro said. Ruedi Reservoir is currently 63 percent full while Green Mountain Reservoir is nearly 46 percent full.

“Where we have large reservoirs that can supplement the flows, yeah, we’ve gotten by,” Martellaro said. “But even that is coming to an end. We are running out. It remains to be seen what the snowpack is like to refill these large holes we’ve put in these reservoirs.”

Water year 2018 Upper Colorado River Basin precipitation accumulation via the NRCS.