JOHN YANG: Tonight on PBS News Weekend, devastating Midwestern floods are putting a spotlight on the condition of America's aging dams.

Then the sports world is taking on a new opponent, climate change.

MAN: Guess what?

Children are not going to be able to play baseball outside, people are not going to be able to play tennis outside.

Something's got to give.

JOHN YANG: And the Hidden History of the Lavender Scare when thousands of federal workers were forced out of their jobs just because they were gay.

(BREAK) JOHN YANG: Good evening, I'm John Yang.

A new post-debate poll out this morning shows a 10 percentage point jump in the proportion of registered voters who say President Biden should not be running for reelection from 63 percent in February to 72 percent on Friday and Saturday.

Most of the registered voters questioned the CBS News poll say Mr. Biden doesn't have the mental and cognitive health to be president.

About 30 percent said neither he nor Donald Trump does.

Three days after the president's unsteady debate performance his backers are still publicly trying to reassure alarm Democrats while former President Trump's supporters are highlighting the night.

REP. JAMES CLYBURN (D) South Carolina: Yes, it was a bad performance.

I've been around these things.

I've been a part of debate preparation before.

And I know what -- when I see what I call preparation overload.

And that's exactly what was going on the other night.

SEN. LINDSEY GRAHAM (R) South Carolina: This idea that Biden had a bad night.

That's not the story.

He's had a bad presidency, had a disastrous debate.

And if you want to look at past performance to judge what's going to happen in the future, God help us all if Joe Biden gets reelected.

JOHN YANG: Today, the Atlanta Journal Constitution editorial page called for Mr. Biden to drop out.

The New York Times took that same position on Friday.

There's extreme weather from the Caribbean to the desert West in the Atlantic barrel quickly intensified to become the earliest category four hurricane on record.

The National Hurricane Center expects the storm to pass just south of Barbados early Monday with St. Vincent and Grenada at the highest risk of the life threatening combination of winds storm surge and waves.

And in Scottsdale, Arizona northeast of Phoenix officials are warning residents to be ready to evacuate.

A wildfire there has charged 4m000 acres to forecast calls for wind gusts and temperatures of up to 110 degrees.

The immigrant family of a 13-year-old boys demanding accountability after the team was killed by Utica, New York police.

Police say they stopped two teens on Friday to ask them about a robbery that led to a foot chase with one of them.

Police released edited body camera video showing a chaotic scene as an officer in the team wrestled on the ground.

The video freezes and a gunshot is heard.

Police say they thought the team pointed a weapon at them it turned out to be a BB or pellet gun.

The officers on leave while the Utica police in New York State Attorney General's Office investigate.

And in France early results in today's first round election pointed to a big win for the country's far-right National Rally party.

Voter turnout was very high in the snap election called by President Emmanuel Macron who centrist party suffered a harsh review.

If the National Rally Party continues to make gains that would be a big shift in French politics.

The first far-right government since Nazi occupation during World War II.

The second round of voting is set for Friday.

Still to come on PBS News Weekend, how the sports world is dealing with climate change and the hit The second round of voting is set for Friday.

Still to come on PBS News Weekend, how the sports world is dealing with climate change, and the Hidden History of LGBTQ people being forced out of the federal government.

(BREAK) JOHN YANG: Flood warnings are likely to remain in effect this week from Wisconsin and Minnesota to Missouri as more heavy rain is forecast.

There's already been historic flooding inundating parts of Nebraska bringing down a bridge in South Dakota.

The lasting image of the week is for Minnesota.

Water surging around the west side of the 114-year old Rapidan dam on the Blue Earth River carrying away a home on a bank just downstream.

Across the country, new weather extremes are testing aging dams.

According to the federal government's most recent climate assessment, the number of extreme precipitation days in the Midwest has gone up 45 percent Since the 1950s.

Del Shannon is the former president of the United States Society on Dams.

It's an organization of professionals who design build and operate dams, and they focus on dam safety.

Del, are the dams that exist now where they built and designed to withstand the sort of extreme weather we're seeing now?

DEL SHANNON, Former President, United States Society of Dams: Well, John, the average age of a dam in the U.S. and their 92,000 dams in the U.S. is 60 years old.

And so the majority of these dams were designed to a standard 60 years or older.

And often, that is insufficient to withstand many of the floods that we're now starting to see.

JOHN YANG: Can dam somehow be retrofitted to bring them up to standard?

DEL SHANNON: Yes, of course, it's a tall task at times because of the immense size of these structures.

But absolutely, and they shouldn't be because water is an irreplaceable resource that we have, there's no plan B for anything other than water.

So these structures must be upgraded if we want to maintain them as assets in our water portfolio.

JOHN YANG: As I understand that the Rapidan dam was damaged by flooding in 2019 and 2020.

And since then, there's been a debate over whether to repair it or remove.

It is enough being done to monitor the state of dams across the country?

DEL SHANNON: You know, it's a complex problem, John.

Each state is responsible for the oversight and the regulation and the inspection of dams, with the exception of the federal government dams, so the federal government is responsible for overseeing their dams.

So we have 50 individual entities charged with overseeing and maintaining them.

And again, with 92,000 dams in our portfolio, it's -- it can be an overwhelming problem and often is.

JOHN YANG: There are maintenance schedules and replacement schedules for highways and bridges are the things do we know enough about the lifecycle of dams?

DEL SHANNON: That's an excellent question, John, we're just starting to delve into that.

We're starting some research later on this year with federally funded research.

But the answer your question is no, we have never gone through a full replacement cycle of our dams, and we don't have a good understanding of the lifecycle.

And that's a much needed area of research and investigation.

JOHN YANG: You know, whenever politicians talk about the need to fix the infrastructure, they talk about bridges, they talk about sewer systems, because these are things that people see and deal with every day.

Is enough attention being paid to dams, do you think?

DEL SHANNON: Well, in my opinion, no.

I'm quite passionate about the topic.

But they're these structures that just silently go about their business day in and day out without a lot of people thinking about them.

But again, as I said earlier, there is no plan B for water, and we're actually from a per capita standpoint, we're declining.

We haven't built new reservoirs, our population is growing, the age of these structures is increasing and the reservoirs and filling the sediment.

All that adds up to a declining per capita storage volume of our reservoirs, both in the U.S. and throughout the world.

JOHN YANG: Is there money in the infrastructure bill for dams?

And is it enough?

DEL SHANNON: There is there is money in there, it's a several billion.

That's a fantastic first step, and I don't want to speak ill of that it's wonderful.

It is a downpayment on additional funding that is needed.

And we need to continue to maintain these structures.

The current estimate of upgrading our existing dams is in the 150 to $160 billion range.

So it is a significant lift that we'll need.

JOHN YANG: Overall, what needs to be done to think to make dam safe and what ought to be done?

DEL SHANNON: So we need more resources, both in funding and in people.

We need to establish a greater workforce focused on specifically on these structures.

That includes increasing funding at the state level, and at the federal level as well.

So all of these things need to be understood and invested in both people and the funding to upgrade these structures.

JOHN YANG: It seems like we hear more frequently these days is about dam failures or overtopping is that the fact or is it just that once one happens we pay attention to the others?

DEL SHANNON: Well, it's actually a complex problem when dams were built.

In the heyday, after World War II, our understanding of hydrology and design was 60 years old.

And so now as we've advanced, we have a better understanding of what the structures, the loading that they need to take the flood designs of that they're designed to withstand, and so that's improved.

The other thing that's gone on is we've had an increase in population.

So once were we had very rural dams that were designed for smaller floods.

Now we have large populations downstream of them, and larger floods are happening and they're overwhelming these dams.

Lastly, we've have a shifting climate and a warmer atmosphere can hold more water and I, and that we're just starting to delve into this and understand it but we believe the size of the floods will continue to increase as our atmosphere temperature also increases.

JOHN YANG: Del Shan and thank you very much.

DEL SHANNON: Thank you John.

JOHN YANG: The Paris Olympics opening ceremony is a little less than four weeks away, organizers have set a lofty goal generate less than half the greenhouse gas emissions of the last two Summer Games.

And it's not just the Olympics.

Across the sports world, there's a new opponent climate change.

Jeffrey Brown reports on how the changing climate is changing the game.

JEFFREY BROWN (voice-over): The crack of the bat throw from the outfield on hallowed ground in American sports and Yankee Stadium in the Bronx, New York.

It's time for that great baseball tradition, the pregame warmup.

But these days here is everywhere.

Warm up means something much more.

DR. ALLEN HERSHKOWITZ, NY Yankees Environment Advisor: Every professional sports community in the United States is being affected by climate change.

JEFFREY BROWN (voice-over): Allen Hershkowitz is the environmental science and sustainability adviser for the New York Yankees, the first environmental scientists hired by a pro team across all sports.

At his urging, the Yankees became the first North American pro team to sign a United Nations pledge to bring down greenhouse gas emissions, because he says the stakes are too high.

ALLEN HERSHKOWITZ: So there is an urgency because guess what?

Children are not going to be able to play baseball outside people are not going to be able to play tennis outside.

Something's got to give.

JEFFREY BROWN (voice-over): The last 10 years have been the warmest ever recorded.

It's pushed the globe into new and uncharted territory, and it's pushing sports to its limits.

MADELEINE ORR, Assistant Professor of Sport Ecology, University of Toronto: The big issue with climate change, the one that's at the top of every sport scientists mind right now is heat.

JEFFREY BROWN (voice-over): metal and or as a sports ecologist and author of a new book, "Warming Up: How Climate Change is Changing Sport."

She use baseball to highlight how rising temperatures have fueled the weather disasters that affect sports bottom line.

The powerful thunderstorms that cause rain delays, the churning hurricanes that have completely swamped ballparks, and massive wildfires to bring dystopian scenes and sometimes game postponements.

MADELEINE ORR: You'd be hard pressed to find a facility manager who's not worried about storms and wildfire and heat and all these things they know about it for a very long time, though, the assumption has been Oh, it's a one off.

And that's really a dangerous assumption because you'll clean up that mess and not necessarily put in place the adaptations that are going to help reduce the risks next time.

DANIIL MEDVEDEV, Tennis Player: One player is going to die.

And they're going to see.

JEFFREY BROWN: Indeed sports are trying to adapt from implementing rest periods at the U.S. Open to help players cope with extreme heat to holding the 2019 World Championship marathon in Qatar at midnight to avoid unsafe temperatures.

For baseball, one adaptation roofs taking fans not out to the ballgame but in.

But experts including Madeline or note that adaptations only go so far.

MADELEINE ORR: On the winter side, it's essentially are we going to have a season at all that's the question and it's because we're not getting as much snow and where we are getting snow.

It's just melting too fast.

So the solution for 50 years has been we will make snow artificially and blow it out of these guns.

But you can make snow all you want and if it's not cold enough outside for the snow to stick on the ground, it's going to mountain.

JEFFREY BROWN (voice-over): On the trails of Mount Bachelor in Bend, Oregon Olympian cross country skier Gus Schumacher is living that reality.

He's not able to rely on snow It's been there in the past.

GUS SCHUMACHER, Cross Country Skier: We've shifted our camp a little bit earlier just so we make sure we get on good snow.

JEFFREY BROWN (voice-over): We read Schumacher as he trained for the Alpine Skiing World Cup and the next Winter Olympics.

Conditions on this day, not bad.

But that wasn't the case back in February, when he raised in the American Birkebeiner in northern Wisconsin.

GUS SCHUMACHER: This year was my first year and there was not a drop of snow on the entire length of trail from cable to Hayward like the actual trail was totally dry.

JEFFREY BROWN (voice-over): The warmest winter in 130 years reduce the 50 kilometer race to a manmade loop of entirely artificial snow.

GUS SCHUMACHER: Climate change has dramatically altered the conditions for winter sports including Nordic skiing.

JEFFREY BROWN: Schumacher has grown so concerned that earlier this year, he traded his ski gear for a suit and appeared on Capitol Hill with the advocacy group protect our winters to share his experience.

GUS SCHUMACHER: Rising temperatures have led to shorter and more erratic winter seasons.

With snow cover becoming increasingly unreliable.

DOUG BEHAR, Senior Vice President, Stadium Operations, New York Yankees: We took the opportunity to say these are the things that we continue to try to stay ahead of reducing our carbon footprint.

So big or small, we're turning over every stone.

JEFFREY BROWN (voice-over): Back at the ballpark.

We met Doug Behar, Yankee Senior Vice President of Stadium Operations.

DOUG BEHAR: Natural cooling you can feel the breeze come through.

JEFFREY BROWN (voice-over): He showed us some of the ways the Yankees are trying to mitigate climate change, not just adapt to it.

Starting at the cavernous great hall where fans enter the stadium constructed in an eco-friendly manner.

It doesn't require air conditioning with cooling is required.

JEFFREY BROWN: A little bit like being in the bottom of a ship or something.

JEFFREY BROWN (voice-over): A new water based cooling system is much more energy efficient.

Recycling and compost bins and every concourse packaged food given away to shelters after every game.

All of it leads to a less electricity use and less food waste, which means fewer greenhouse gases that warm the planet.

ALLEN HERSHKOWITZ: 90 percent of our environmental work the fans don't see because they relate to our equipment.

They don't know that we're using LED lights that reduced our lighting emission by 60 percent.

You know a lot of it is invisible.

JEFFREY BROWN (voice-over): What's much more visible Allen Hershkowitz says is the influence sports and athletes have unmilled use.

ALLEN HERSHKOWITZ: Guess what they learned from their sports organization, sports loyalty is handed down generation to Generation, less than 20 percent of Americans regularly follow science, over 80 percent regularly follow sports.

The most influential role models are athletes.

If athletes are selling cars, if they're endorsing banks, if they're selling pizza, why can't they sell environmental literacy?

JEFFREY BROWN (voice-over): The Yankees haven't won a championship since 2009.

But they're off to a great start this year.

They'll be hard sees plenty more to do on and off the field.

DOUG BEHAR: The Yankees are doing our best to try to stay ahead of the curve lead where we can and certainly do all the things that are necessary to be productive and responsible.

JEFFREY BROWN: While winning championships.

DOUG BEHAR: Absolutely.

JEFFREY BROWN (voice-over): For PBS News Weekend.

I'm Jeffrey Brown at Yankee Stadium in the Bronx.

JOHN YANG: On this final day of LGBTQ Pride Month, tight installment of our Hidden History series isn't about an individual.

It's about an episode, how the anti-communist paranoia that gripped Washington at the dawn of the Cold War led to an often overlooked chapter in LGBTQ history.

Fan by Senator Joseph McCarthy's headline grabbing claims fears of communist subversion led to the hunt for communists in the government.

MAN: Department of Justice officials had promised further arrest as the crackdown on suspected subversives gathers momentum.

JOHN YANG: McCarthy explicitly linked communism with LGBTQ people, and some even said they were the bigger threat.

The Red Scare had spawned the Lavender Scare the name taken from Senator Everett Dirksen his reference to gay men as lavender labs.

A 1950 Congressional investigation concluded that LGBTQ people were unsuitable for federal employment and posed a security risk because fear of exposure made them susceptible to blackmail.

Thousands of workers across the government were investigated, interrogated and forced from their jobs.

Over time society's attitudes towards LGBTQ people changed but until 1975, they were still barred from the civil service.

And it wasn't until the 1990s that President Bill Clinton ended official discrimination based on sexual orientation for all non-military government workers.

Marc Stein is a history professor are at San Francisco State University.

Marc, for someone who's younger than a baby boomer in certainly in probably the age of your students may see all the celebrations that we've had during this Pride Month and wonder where that the attitudes wonder about the attitudes that led to this in the 1950s and early 1960s.

How do you explain it?

MARC STEIN, San Francisco State University: Well, it's complicated.

But I think most historians believe there were really three pillars of anti LGBT Animus.

Throughout the 20th century, one was religion that regarded homosexuality and gender transgression as a sin.

One was law and the state that regarded those expressions as criminal behavior.

And then there were science and medicine and psychiatry, which regarded homosexuality and transgenderism as signs of illness and sickness.

And so you put those three together, you have immense cultural authority, political authority, coming down hard on LGBTQ people.

JOHN YANG: What was it like to be an LGBTQ person who's working in the government at this time?

MARC STEIN: Well, for those who were in Washington, DC, there was a developing vibrant community based culture in bars and parks in parties.

And so, one could have a relatively full and interesting and dynamic, private life.

But the workplace was a different story.

And if you worked for the federal government in Washington, DC or elsewhere, there was the ever present threat that you could be outed, that you could be threatened.

And this affected more than just people who identified as LGBTQ, because even rumor or innuendo say if a person wasn't married, or didn't go out after work and behave in conventionally straight ways.

That could cast a pall of suspicion even on workers for the federal government who did not identify as LGBTQ.

JOHN YANG: As we said, one of the rationales that government officials offered for this was security risks.

They're the susceptibility of blackmail.

But in an ironic way, didn't the some government officials actually sort of prove that case about being able to coerce or coerce federal workers.

MARC STEIN: Yes.

So you know, while there is limited evidence that there were instances of blackmail, from external actors, what you say is absolutely true, that oftentimes the worst forms of blackmail came from within the federal government.

And so the threat of being outed in the workplace could itself lead to a form of blackmail, within the workplace.

JOHN YANG: Why do you think this episode may have been forgotten it largely by now?

MARC STEIN: Well, for decades, there was really intense censorship on the teaching of LGBTQ history, in public and private schools in the United States.

Certainly, when I was growing up in the 1960s, 1970s, and into the 1980s, there was little or nothing ever said about LGBTQ history.

And so in part, I think this has been forgotten for that reason.

Also, during the era itself, there were there were euphemisms there were non-explicit ways of talking about this phenomena.

So there might be discussions of perverts of deviance of misfits.

And so that wouldn't necessarily be understood or interpreted by the broad population as referencing LGBTQ people.

JOHN YANG: A lot of these policies were on the books maybe not observed, but they were still official policies until the 1990s and the early 2000s.

Why did it take so long to change?

MARC STEIN: Well, I think actually, we're still living with the legacies of those policies today.

And maybe that's something we can also talk about, but the for the earlier decades, those three pillars of anti LGBTQ oppression, religion, the state and science continued to exhibit many of those same attitudes for decades.

And so it wasn't until 1973 that the American Psychiatric Association declassified homosexuality as a mental illness, and even after that the APA continued to regard as illnesses, gender identity dysphoria or sexual orientation disturbance, and the other two pillars continued to express intense anti LGBTQ animus even after the official policies changed on civil service employment.

JOHN YANG: And talk about some of the legacies that you feel we're still living with from this.

MARC STEIN: Well, while it's no longer officially acceptable to refuse to hire someone for a government work, federal government work or to fire someone for federal government work based on sexual orientation and gender identity.

There's still a lot of artificial discrimination that goes on.

And we still see the traces.

I think the legacies of those earlier policies in things like banning the teaching of gender and sexuality in public schools, which a number of states have done in recent years, and we still see it, I would say in the refusal of many public schools and private schools to teach LGBTQ history, it's as if this is just an unacceptable topic, inappropriate for children.

And in that way, that form of censorship and repression really is working against fuller democratization, fuller openness and fuller educational excellence.

JOHN YANG: Mark Stein of San Francisco State University.

Thank you very much.

MARC STEIN: Thank you.

JOHN YANG: And that is PBS News Weekend for this Sunday.

I'm John Yang.

For all of my colleagues, thanks for joining us.

Have a good week.