Washington, D.C
Aggressive Algae Bloom Clogged Water System, Prompting Boil Water Advisory in D.C. and Parts of Virginia – Inside Climate News
A severe algae bloom clogged equipment at one of the treatment facilities providing drinking water in the Washington region, forcing officials to declare a boil-water advisory on the night of July 3—as thousands of visitors arrived to celebrate Independence Day.
The advisory was lifted the morning of July 4. But the incident was an ominous sign of how warming water temperatures caused by climate change can disrupt essential civic services.
The algal blooms caused a drop in water supply at the Dalecarlia Water Treatment Plant on the Maryland-D.C. border. All water treatment operations were switched to the McMillan Treatment Plant in Northwest D.C. to ensure adequate supply of water, the District of Columbia Water and Sewer Authority (DC Water) said in its July 3 advisory.
The disruption in water supplies affected the entire District of Columbia and parts of Arlington, Virginia, including the Pentagon, Arlington National Cemetery and Reagan National Airport. Among the blooms’ impact: increased turbidity, a measure of cloudiness in water.
The U.S. Army Corp of Engineers (USACE) operates the treatment plants located in D.C. and supplied by the Washington Aqueduct, which collects, treats and pumps drinking water for nearly 1 million customers in Washington, Arlington County and other areas in northern Virginia.
Explore the latest news about what’s at stake for the climate during this election season.
The algae intruded at a time when demand for water was particularly high due to the influx of visitors and possible firefighting activities related to the annual fireworks display on the National Mall.
“DC Water issued a precautionary boil water advisory to protect public health and safety due to a sharp reduction in the volume of water being supplied by the Army Corps of Engineers’ Washington Aqueduct and due to the Aqueduct expressing concerns that they might be unable to comply with strict U.S. EPA water quality standards while simultaneously attempting to increase water supply volumes to levels adequate to meet DC Water’s customer demands,” said Sherri Lewis, senior manager of communications at DC Water, in emailed remarks. “The combined output of treated water from both of the Aqueduct’s plants was insufficient to meet DC Water’s water consumption demands.”
Lewis said the week of the July 4th holiday has historically been one of DC Water’s highest water demand days of the year.
Affected customers scrambled to stock up on bottled water supplies after the advisory was announced, quickly emptying out aisles in supermarkets and local stores.
“We had floating algae mats along the top of our sedimentation basin at our Dalecarlia Treatment Plant, which then washed into the filter building, clogging filters in the process,” said Cynthia Mitchell, a public affairs specialist with the U.S. Army Corps of Engineers.
The sedimentation portion of the water filtration process removes suspended particulates in water. In emailed comments to Inside Climate News, Mitchell said the situation at Dalecarlia led to a decrease in supply, while the McMillan Treatment Plant continued to operate under normal conditions.
“Our recent algae bloom was not a cyanobacterial harmful algae bloom—we had green algae which does not pose a risk to human health,” Mitchell added.
The U.S. Environmental Protection Agency EPA, warns that “blooms of red tides, blue-green algae, or cyanobacteria can result in severe impacts on water quality, human health, aquatic ecosystems, and the economy.”
In the case of the July 3 event, it was the sheer amount of algae that caused problems. The region’s record-high temperatures are driving growth, and climate change is expected to worsen the situation, Mitchell said.
“Washington Aqueduct staff that have served for decades, including General Manager Rudy Chow with 40 years of experience in the water utility industry, agree the severity of algae blooms this summer is unprecedented,” Mitchell said.
DC Water’s Lewis said several other utilities that use the Potomac River as one of their water supply sources, such as Fairfax Water in Virginia and the Washington Suburban Sanitary Commission in Maryland, encountered and successfully treated these same algal blooms.
Nitrogen, key fuel for algae, flows into water bodies from sewage overflows and runoff. Bill Dennison, a professor and vice president at the University of Maryland Center for Environmental Science, said the Potomac River has historically had high levels of pollution from sewage but now agriculture and stormwater runoff is the biggest source of pollution in the Chesapeake Bay watershed.
“Generally, both cyanobacteria and green algae form in the Potomac River,” Dennison said. “Fortunately, green algae don’t tend to be as toxic as cyanobacteria. But they’re not a pleasant addition to the environment and can clog the waterways … and produce bad taste in drinking water.”
Climate change contributes a one-two punch. More rain instead of snow in the winter leads to extra pollution runoff earlier in the season, Dennison said. And warming temperatures allow algae to bloom earlier in the summer than before.
DC Water officials said they are reviewing their actions and communications to the public about the July 3 event to determine what can be improved.
Lewis said that unlike the majority of other public water utilities, DC Water does not have a second source of water and is fully dependent on the Aqueduct to supply its needs. “It is also extremely unusual for a water utility serving a large metropolitan city not to also have direct responsibility for water supply and water treatment. DC Water will be reviewing the Aqueduct’s actions to determine if any changes are necessary to ensure proper notification steps are taken in a timely manner,” she said.
While greater D.C. avoided major calamity with this algae bloom, other cities haven’t been as lucky. In 2014, the water supply of Toledo, Ohio, had to be shut down because of a harmful algal bloom in Lake Erie, and the toxin associated with that algae could not be destroyed by boiling. Half a million people could not use water supplies for days. Agricultural runoff was later declared the cause of the ordeal.
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Washington, D.C
Tax expert explains DC filing season amid Congress-District dispute
WASHINGTON (7News) — D.C. taxpayers may be confused by back-and-forth between the D.C. City Council and Congress over taxprovision. The city’s financial officer sent a letter to Mayor Muriel Bowser and D.C. Council Chair Phil Mendelson, that said the District’s tax laws will not change, despite recent actions by Congress.
7News spoke to director of Tax Policy at the Center for American Progress Corey Husak to explain the complicated tax policy.
“The short answer is, nothing changes. Filing Season can continue as it has been, continue as planned, and according to the laws as we understood them in January,” said Husak.
“If you’ve already filed your taxes, you don’t have to change anything. And if you want to file your taxes, the rules are still the same as they were on the books before,” said Husak.
RELATED | DC Council Chairman talks taxes, budget, bodycams, federal surge
Chief Financial Officer Glen Lee’s revenue estimate issued Friday does not include an estimated $180 million expected this fiscal year from the city’s decoupling law, “due to the uncertainty of the associated revenue as a result of Joint Resolution 142,” according to a released letter.
“The CFO was in a tough spot here. If he agreed with Congress, then businesses and overtime workers will get bigger refunds. But if he agreed with the Mayor and the Attorney General, then families with children and lower income workers would get bigger tax cuts,” said Husak.
SEE MORE | Development of new Commanders stadium scrutinized at DC oversight hearing
“We as District residents can’t control, you know what happens in the courts, what happens in, you know, what Congress does in the future,” said Husak. “But for now, the CFO has said, you know this is, this is a law as it stands, and the law that I’m going to enforce so, you know, file your legally obligated taxes, and maybe in the future, there’ll be a surprise.”
WATCH THE FULL INTERVIEW
7News spoke to director of Tax Policy at the Center for American Progress Corey Husak to explain the complicated tax policy (7News).{ }
Washington, D.C
CHERRY BLOSSOM COUNTDOWN: Peak Bloom prediction drops Thursday
WASHINGTON (7News) — The nation’s capital is just about ready to be transformed into a breathtaking pastel landscape of cherry trees in bloom. The famed blossoms around the Tidal Basin are not only a symbol of spring’s arrival, but also of a long-standing friendship — a gift of more than 3,000 trees from Tokyo, Japan, to the United States in 1912.
So what is considered “Peak Bloom”?
The National Park Service (NPS) defines peak bloom as the time when at least 70% of the Yoshino cherry trees around the Tidal Basin have opened their blossoms. This is the period when the blossoms appear most full and spectacular and most ideal for photos, and soaking up spring’s beauty here in DC.
Because cherry trees respond to the cumulative effects of winter and spring weather, especially daily temperatures, it’s very difficult to predict peak bloom more than about 10 days in advance. Warm spells accelerate blooming; cold snaps slow it down.
Average Timing — What History Shows
Since 1921 overall, national data indicate peak bloom typically fell around early April (April 4), based on historical averages.
Since 1990, the average has kept shifting earlier and earlier. In fact, the last 6 years our peak has occurred in late March.
These shifts reflect how warmer springs have nudged peak bloom earlier over the decades.
Earliest & Latest Blooms on Record
Earliest peak bloom: March 15 — recorded in 1990.
Latest peak bloom: April 18 — recorded in 1958.
Of course, most years fall between those dates, with the last week of March to the first week of April historically being the most consistent window for peak bloom.
Earliest Peak Bloom Washington DC
Recent peak blooms show how variable and climate-dependent the timing can be:
2025: The National Park Service predicted peak bloom between March 28–31 (and confirmed the official peak around March 28).
2024: Peak bloom arrived very early, on March 17, several days ahead of NPS projections — tied for one of the earliest peaks in decades.
These examples demonstrate not only how much each season can differ, but also a trend toward earlier spring blossoms in recent years.
What to Expect for Spring 2026
As of early March 2026, the cherry trees are still dormant. The buds haven’t begun significant growth yet. The weather will become more critical in the weeks leading up to the bloom will be the biggest factor in determining when peak bloom happens in 2026.
Heavy winter cold, as experienced this year, tends to delay bloom compared with recent early springs. In contrast, an early warm stretch could push peak bloom earlier — as long as it doesn’t come with subsequent frost.
Look for the green bud stage first. This is when the buds are small, tight, and green, with no sign of petals yet. Trees are still several weeks from blooming.
Tips for Cherry Blossom Visitors
Plan in the “sweet spot” — peak bloom often lasts a few days to about a week, but weather (rain, wind, heat) can shorten that window.
Visit slightly before or after the predicted peak dates for smaller crowds and extended color. Blossoms can be gorgeous even before 70% bloom or as petals begin falling.
Check NPS updates and First Alert Weather forecasts in late March for tweaked peak bloom dates.
The cherry blossoms of Washington, D.C. remain one of the most iconic harbingers of spring in the U.S., and while exact bloom dates vary year-to-year, history and natural patterns point to late March through early April as your best bet for seeing the Tidal Basin in full floral glory.
Washington, D.C
Fact Check Team: Iran conflict revives Washington fight over who can authorize US force
WASHINGTON (TNND) — As the war in Iran intensifies across the Middle East, a constitutional battle is unfolding in Washington over a fundamental question: Who has the authority to declare war, Congress or the president?
The debate focuses on the War Powers Resolution, a 1973 law designed to prevent years-long military conflicts without congressional approval. Lawmakers passed the measure in the aftermath of the Vietnam War to reclaim authority they believed had drifted too far toward the executive branch.
What Is the War Powers Resolution?
The War Powers Resolution was intended to put limits on a president’s ability to send U.S. troops into combat without Congress signing off.
Under the law, a president can deploy forces into hostilities only if Congress has formally declared war, passed a specific authorization for the use of military force, or the U.S. has been attacked.
The resolution also sets strict deadlines.
The president must notify Congress within 48 hours of introducing U.S. forces into hostilities. From there, a 60-day clock begins. If Congress does not approve the military action within that time, troops must be withdrawn — though the law allows an additional 30-day wind-down period.
Some argue the law was crafted to prevent “never-ending wars.” While others say presidents from both parties have routinely stretched and sidestepped its requirements.
WASHINGTON, DC – JANUARY 14: Sen. Cory Booker (D-NJ) visits with Senate pages in the basement of the U.S. Capitol Police ahead of a vote on January 14, 2026 in Washington, DC. Republicans voted to block a Venezuela war powers resolution after receiving assurances from President Donald Trump and Secretary of State Marco Rubio of no U.S. forces remaining in Venezuela and pledges for congressional involvement in major future operations. (Photo by Chip Somodevilla/Getty Images)
What Does the Constitution Say?
The War Powers Resolution is rooted directly in the U.S. Constitution.
Article I, Section 8 gives Congress — not the president — the power “to declare War.”
Article II, Section 2 names the president as Commander-in-Chief of the Army and Navy.
In simple terms, Congress decides whether the country goes to war. The president directs the military once it is engaged.
The framers intentionally split that authority. Their goal was to avoid concentrating too much war-making power in one person — likely a reaction to the monarchy they had just broken away from.
But how that balance plays out in real time is often a legal and political fight. At times, disputes over war powers have reached the courts, though Congress and the executive branch frequently resolve them through political pressure rather than judicial rulings.
A Pattern of Stretching the War Powers Resolution
Essentially, every president since 1973 has pushed the boundaries of the War Powers Resolution rather than fully complying with its original intent. As the Council on Foreign Relations explains, the resolution was designed to “provide presidents with the leeway to respond to attacks or other emergencies” but also to **require termination of combat after 60 to 90 days unless Congress authorizes continuation.”
For example:
- Ronald Reagan ordered the U.S. invasion of Grenada in 1983 without prior congressional authorization, later reporting to Congress in a manner “consistent with” the resolution.
- Bill Clinton directed the 1999 NATO air campaign in Kosovo after congressional authorization efforts failed, continuing U.S. engagement beyond the WPR’s typical 60-day reporting window.
- Barack Obama oversaw U.S. participation in the 2011 Libya campaign, arguing that limited strikes did not trigger the full force of the WPR’s time limits.
In more recent years, Donald Trump’s administration has once again brought these issues to the forefront.
War Powers Arguments from the White House
The Trump administration’s principal legal rationale has centered on two points:
Short-term strikes or limited military actions do not always trigger the full 60-day clock under the War Powers Resolution, especially when described as defensive, limited in scope, or tied to national security emergencies rather than prolonged hostilities. In some cases, the White House relies on prior Authorizations for Use of Military Force (AUMFs) or other statutory authorities rather than seeking new congressional approval.
Current Public Opinion on Iran Strikes
Public opinion reflects significant skepticism about the current U.S. military engagement with Iran. A recent Reuters/Ipsos poll found that just 27% of Americans support the recent U.S. and allied strikes on Iran, while 43% disapprove and 29% remain uncertain.
Another national poll conducted by SSRS for CNN found that nearly 60% of U.S. citizens disapprove of the military actions, and a similar share said that President Trump should seek Congressional authorization for further action.
Beyond polling, internal deliberations in Congress have already begun. Both Democratic and Republican lawmakers have pushed for votes on war powers resolutions that would seek to limit or require authorization for further military action against Iran. Past attempts to pass similar restraints have failed, reflecting deep partisan divisions and the complexities of enforcing the War Powers Resolution.
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