The Summit County Sheriff’s Office announced Tuesday afternoon that the Blue River had returned to safe conditions would be reopening for recreational activities immediately.
On June 1, the Sheriff’s Office and the town of Silverthorne were notified by Denver Water that flow levels were rapidly increasing to 1,000 cubic feet per second, presenting safety concerns for river recreationists.
Sheriff Jaime FitzSimons and Silverthorne Police Chief John Minor decided to temporarily close the river from the base of the Dillon Dam to the Sixth Street Bridge, where the water was high enough to injure someone floating past that point.
On Tuesday afternoon, the Sheriff’s Office and town got the thumbs up from Denver Water that flow levels on the river had significantly decreased and were once again safe for recreation. At 1 p.m. Tuesday, the Blue River below Dillon Dam was flowing at 301 cfs.
While the river has opened back up, officials are reminding anyone heading out on the water to use caution. Members of the public are encouraged to review the Summit County Swift Water Safety and Flood Preparedness Guide available on the county’s website. The guide contains information on the history of high water events in the county, along with instructions for building sandbag levees, household checklists, flood insurance information, safety tips for recreating and more.
Desertification is the degradation of land in arid, semi-arid and dry sub-humid areas. It is caused primarily by human activities and climatic variations. Desertification does not refer to the expansion of existing deserts. It occurs because dryland ecosystems, which cover over one third of the world’s land area, are extremely vulnerable to overexploitation and inappropriate land use. Poverty, political instability, deforestation, overgrazing and bad irrigation practices can all undermine the productivity of the land.
The World Day to Combat Desertification and Drought is observed every year to promote public awareness of international efforts to combat desertification. The day is a unique moment to remind everyone that land degradation neutrality is achievable through problem-solving, strong community involvement and co-operation at all levels.
Even more specially these times, considering the COVID-19 situation. Actions based on the clear understanding of rights, rewards and responsibilities of land management can help address the COVID-19 fallout by tackling one of the primary environmental drivers of emerging infectious disease outbreaks. At the same time, strengthening the resilience of our food and water systems, can help reduce the effects of the pandemic on global poverty and food insecurity. Today, the motto “healthy land = healthy people” promoted by the Convention to Combat Desertification, is more true than ever.
2020 Theme: Food. Feed.Fibre. – the links between consumption and land
This year’s observance is focused on changing public attitudes to the leading driver of desertification and land degradation: humanity’s relentless production and consumption.
As populations become larger, wealthier and more urban, there is far greater demand for land to provide food, animal feed and fibre for clothing. Meanwhile, the health and productivity of existing arable land is declining, worsened by climate change.
To have enough productive land to meet the demands of ten billion people by 2050, lifestyles need to change. World Day to Combat Desertification and Drought, under the slogan “Food. Feed. Fibre.” seeks to educate individuals on how to reduce their personal impact.
Food, feed and fibre must also compete with expanding cities and the fuel industry. The end result is that land is being converted and degraded at unsustainable rates, damaging production, ecosystems and biodiversity.
Food, feed, and fibre is also contributing to climate change, with around a quarter of greenhouse gas emissions coming from agriculture, forestry and other land use. Clothing and footwear production causes 8 per cent of global greenhouse gas emissions, a figure predicted to rise almost 50 per cent by 2030.
With changes in consumer and corporate behaviour, and the adoption of more efficient planning and sustainable practices, there could be enough land to meet the demand. If every consumer were to buy products that do not degrade the land, suppliers would cut back the flow of these products and send a powerful signal to producers and policymakers.
In order to celebrate this observance and create awareness of this day, the UNCCD has prepared several activities: an on line event, a Youtube short film series related to the theme and the Contest Become #UNCCDLandHeroes, where young candidates propose a specific solution to limit the footprint that our production and consumption of food, feed and fibre leave on the land. The winner will be announced on 17 June.
Since the start of the coronavirus pandemic, use of the term “herd immunity” has spread almost as fast as the virus. But its use is fraught with misconceptions.
In the U.K., officials brieflyconsidered a herd immunity strategy to protect the most vulnerable members of its population by encouraging others to become exposed and develop immunity to the virus. Others reignited the discussion by focusing on how far we are from herd immunity. But trying to reach herd immunity without a vaccine would be a disastrous pandemic response strategy.
As mathematics and computer science professors, we think it is important to understand what herd immunity actually is, when it’s a viable strategy and why, without a vaccine, it cannot reduce deaths and illnesses from the current pandemic.
What is herd immunity?
Epidemiologists define the herd immunity threshold for a given virus as the percentage of the population that must be immune to ensure that its introduction will not cause an outbreak. If enough people are immune, an infected person will likely come into contact only with people who are already immune rather than spreading the virus to someone who is susceptible.
Herd immunity is usually discussed in the context of vaccination. For example, if 90% of the population (the herd) has received a chickenpox vaccine, the remaining 10% (often including people who cannot become vaccinated, like babies and the immunocompromised) will be protected from the introduction of a single person with chickenpox.
But herd immunity from SARS-CoV-2 is different in several ways:
1) We do not have a vaccine. As biologist Carl Bergstrom and biostatistician Natalie Dean pointed out in a New York Times op-ed in May, without a widely available vaccine, most of the population – 60%-85% by some estimates – must become infected to reach herd immunity, and the virus’s high mortality rate means millions would die.
2) The virus is not currently contained. If herd immunity is reached during an ongoing pandemic, the high number of infected people will continue to spread the virus and ultimately many more people than the herd immunity threshold will become infected – likely over 90% of the population.
3) The people most vulnerable are not evenly spread across the population. Groups that have not been mixing with the “herd” will remain vulnerable even after the herd immunity threshold is reached.
Reaching herd immunity without a vaccine is costly
For a given virus, any person is either susceptible to being infected, currently infected or immune from being infected. If a vaccine is available, a susceptible person can become immune without ever becoming infected.
Without a vaccine, the only route to immunity is through infection. And unlike with chickenpox, many people infected with SARS-CoV-2 die from it.
A vaccine is the only way to move directly from susceptibility to immunity, bypassing the pain from becoming infected and possibly dying.
Herd immunity reached during a pandemic doesn’t stop the spread
An ongoing pandemic doesn’t stop as soon as the herd immunity threshold is reached. In contrast to the scenario of a single person with chickenpox entering a largely immune population, many people are infected at any given time during an ongoing pandemic.
When the herd immunity threshold is reached during a pandemic, the number of new infections per day will decline, but the substantial infectious population at that point will continue to spread the virus. As Bergstrom and Dean noted, “A runaway train doesn’t stop the instant the track begins to slope uphill, and a rapidly spreading virus doesn’t stop right when herd immunity is attained.”
If the virus is unchecked, the final percentage of people infected will far overshoot the herd immunity threshold, affecting as many as 90% of the population in the case of SARS-CoV-2.
Proactive mitigation strategies like social distancing and wearing masks flatten the curve by reducing the rate that active infections generate new cases. This delays the point at which herd immunity is reached and also reduces casualties, which should be the goal of any response strategy.
Herd immunity does not protect the vulnerable
People who are particularly vulnerable to COVID-19, such as people over 65, have been urged to stay inside to avoid exposure. However, many of these people live and socialize in communities of people in the same cohort.
Even if the herd immunity threshold is reached by the population at large, a single infected person coming in contact with a vulnerable community can cause an outbreak. The coronavirus has devastated nursing homes, which will remain vulnerable until vaccines are available.
How to respond to a pandemic without a vaccine
Without a vaccine, we should not think of herd immunity as a light at the end of the tunnel. Getting there would result in millions of deaths in the United States and would not protect the most vulnerable.
For now, washing hands, wearing masks and social distancing remain the best ways to lessen the destruction of COVID-19 by flattening the curve to buy time to develop treatments and vaccines.
Platte River Power Authority seeking to define pathway to 100% non-carbon energy
The Platte River Power Authority plans to cease production of electricity from its 280-megawatt Rawhide power plant north of Fort Collins by 2030, 16 years before its original retirement date.
The utility delivers electricity to Fort Collins and also three other owner communities: Loveland, Longmont, and Estes Park.
The decision to set the retirement resulted from a confluence of several factors. One of them, a new survey of customers this spring in the four towns and cities, once again affirmed broad support for non-carbon energy resources. The survey found 63% of residential customers viewed the non-carbon resources as somewhat or very important.
Platte River also has an 18% interest in two coal-burning units at Craig Generating Station. Unit one is scheduled to end production in 2025 and unit 2 no later than 2030.
The stage for today’s announcement was set in December 2018 when Platte River directors adopted a policy calling for 100% non-carbon energy mix by 2030. The resource diversification policy identified nine advancements that must occur in the “near term” to achieve that 2030 goal. They include active participation by Platte River in an organized regional market; matured battery storage performance and declined costs; and increased investment in transmission and distribution infrastructure.
Platte River is among most Colorado utilities who will be joining energy imbalance markets in the next two years. There is common agreement, however, that deep decarbonization such as planned by Platte River and other Colorado utilities will require participation in a robust regional transmission organization, or RTO, such as operate in other parts of the country.
Xcel Energy in December 2018 gained national attention when it announced its intentions to reduce carbon emissions 80% by 2030 as compared to 2005 levels. It operates in six states and supplies more than 60% of energy consumed in Colorado. Xcel said it planned to achieve emission-free electricity by 2050, but like Platte River, said technology must continue to evolve for it to achieve that goal.
Holy Cross Energy, the co-operative serving Vail and Aspen, has shown innovation that has attracted national attention, but nonetheless has committed only to a 70% carbon-free goal called Seventy70Thirty. It could, however, achieve that in 2021.
Several coal plants in Colorado have already been retired, and many more large units will be retired in the next decade. Only the plants at Hayden and Brush and Comanche 3 at Pueblo are currently scheduled to remain in operation. Xcel is the sole or majority owner of the three plants.
Spread of covid-19 interrupted Platte River’s integrated resource planning process, which had been scheduled to include public meetings. But managers of the utility decided it was best to announce the retirement to support state regulatory timelines. Colorado last year adopted a law that identified a target of 80% emissions reduction from the electrical sector by 2030 and 50% more broadly in the state’s economy.
“Although circumstances associated with the coronavirus prevent us from making this announcement in alignment with our current IRP process, we need to continue moving forward to reach our Resource Diversification Policy’s 100% noncarbon goal,” said Jason Frisbie, chief executive of Platte River.
“Rawhide Unit 1 has served us extremely well for the past 36 years,” said Wade Troxell, Platte River Board chair and Fort Collins mayor, “but the time has come for us to move toward a cleaner future with grid modernization and integration while maintaining our core pillars of providing reliable, financially sustainable and environmentally responsible energy and services.”
Platte River Power projects that 55% of electricity will come from coal this year, supplemented by 19% from hydropower, 17% from wind, 3% from solar. Another 1% comes from natural gas; and 5% comes from purchased power, which could include fossil fuels.
Construction to build Rawhide Unit 1 began in 1979 and commercial operations started in 1984 and has performed with exceptional reliability, capacity and environmental performance. It had been scheduled to retire in 2046.
“Unit 1 has outperformed nearly every other coal plant of its type in the nation and that is a testament not only to its design but also to the people who run it,” noted Frisbie, who began his career at the Rawhide Energy Station and became its plant manager before being promoted to chief operating officer, then general manager and CEO of Platte River.
In addition to Unit 1, the 4,560-acre Rawhide Energy Station also hosts five natural gas combustion turbines and a 30 MW solar farm, along with another 22 MW of solar power (with battery storage) currently under construction. Energy from the 225 MW Roundhouse wind farm located in southern Wyoming will be delivered to the Rawhide Energy Station and then to the owner communities.
Frisbie said plans will be developed to smoothly transition 100 workers to new roles at the other generation resources at Rawhide after the coal-plant closure. Following its retirement, Unit 1 will undergo a lengthy decommissioning process.
Coal for Rawhide comes from the Antelope Mine near Gillette, Wyo.
Allen Best is a Colorado-based journalist who publishes an e-magazine called Big Pivots. Reach him at firstname.lastname@example.org or 303.463.8630.