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As rainfall travels down the hills of the Parkfairfax neighborhood, the momentum sweeps it past the slim gutters meant to catch the water, propelling it further downhill to devastating effect. But fortunately, with a surge of political and financial interest being poured into flood mitigation over the last few years, stormwater isn’t the only thing gaining momentum.

Among the larger flooding infrastructure projects going around the city are a handful of smaller “spot improvements” that could play a big role when the next major storm hits.

In the Parkfairfax neighborhood, the Department of Transportation and Environmental Services has been installing 13 inlets that the city hopes will help catch some of the stormwater the current storm drains aren’t getting.

Last week, civil engineers Brian Rahal and Ehsanullah Hayat were overseeing the inlet project, the largest of the stormwater spot improvements in the city to date.

“The biggest problem with this area is it’s steep,” said Rahal. “The inlets were put in decades ago and are small, so the gutters get filled with runoff quickly.”

Every flooding issue needs its own diagnosis and in Parkfairfax — unlike Old Town’s massive stormwater infrastructure project — Rahal said the issue isn’t one of capacity.

“There’s capacity here, but we need to get [the water] in,” Rahal said.

The city is installing 13 inlets: nine are redone inlets designed to make the current storm drains significantly larger and four are completely new inlets. The larger inlets are designed to divert more of the stormwater that momentum currently carries past the antiquated ones built decades ago in Parkfairfax. Last year, the city worked on around seven inlet projects across the city.

“That should capture most of it,” Rahal said. “That should drastically reduce the impact.”

Stormwater also tends to have a snowballing effect, where water can flow down to the same locations from different locations and the problems can quickly escalate. The intersection of Holmes Lane and Martha Custis Drive, where a few of the new inlets are being installed, is one such confluence of watersheds.

Rahal has worked in stormwater management in Alexandria for 12 years and said the increase in flooding problems has been gradual but increasingly noticeable.

“It increase really started in rainfall around 2010, but we started noticing it in 2015,'” Rahal said. “It was spotty, then we had record rainfall in 2018 and in 2019 we had the big storms.”

There was torrential flooding across the region in 2019, but Alexandria’s seen continued heavy rainfall every year since. New rainfall records were set in Alexandria last July.

The battering of the city from back-to-back flooding caused intense public scrutiny of the city’s stormwater mitigation, drawing backlash from sources ranging from the former sheriff to a locally popular Twitter account. The city worked to fast-track flood mitigation projects, but the speed of progress was limited by the design process.

Rahal said the stormwater utility fee helped give the city the resources it needed to move more quickly on some of these projects.

“That really changed the narrative,” Rahal said. “In 2014 we were concerned about the water quality mandate and focused more on water quality, then the narrative shifted to a higher priority for flood mitigation.”

Now, Rahal said the city is juggling larger and longer-term infrastructure projects with shorter-term spot improvements.

“We’ve taken a two-pronged approach,” Rahal said. “There are big projects that take time and we’re busy designing them, but at the same time we’re making spot improvements as much as we can in the time we have to affect change.”

Looking at the slim inlets they’re replacing, Rahal says he thinks back to their initial installation and has to remember how much the rainfall levels have changed since they were installed.

‘They had no way of knowing the stormwater issues we’d face,” Rahal said, “so it’s up to us to mitigate them.”

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Power outages in central Alexandria (image via Dominion Energy)

There are around 1,629 Alexandrians without power after this morning’s storms.

Most of those outages are in the city’s central Seminary Hill and Taylor Run neighborhoods.

There are 943 residents affected by the Seminary Hill outage and 608 in Taylor Run. There are other smaller outages throughout Old Town. The Dominion Energy website said crews are assessing the damage.

Alexandria isn’t alone, neighboring Arlington is starting to see significant outages as well.

Dominion’s outage map is available online.

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Furniture drying out after flooding in Del Ray after a massive storm on August 14, 2021. (via DrainALX/Twitter)

Alexandria still bears scars from the intense 2019 floods — notably the ongoing closure of much of Four Mile Run. Local residents are still reeling from floods since then, but some in city government have been pushing over the last few years to better prepare both city residents and infrastructure for future flooding.

There’s a suite of major stormwater infrastructure projects ongoing around Alexandria, but another major focus from the city has been working with locals to help flood-proof homes.

Last week, the city opened the application window for the Stormwater Utility Fee Credit Program.

The stormwater utility fee is an additional utility fee for locals, with funding from the fee going to support flooding infrastructure projects. For the average single-family homeowner, it’s a roughly $294 fee. The credit program incentivizes locals to install flood-mitigation projects on their property in exchange for credits toward their stormwater utility fee.

Participation in the program has been spotty, but Jesse Maines, division chief for Stormwater Management, said the new changes are the biggest since the program launched in 2018 and aim to make the credits more accessible.

Maines said changes include decreased documentation demands and increases in what’s covered by the credits. Originally the program was more focused on projects that improve water quality, but now many DIY projects focused on preventing damage to property from flooding are included.

Those home improvement projects, called dry floodproofing, keep properties safe from the impacts of floodwater. That can include things like building plexiglass over basement windows, raising air conditioning units off the ground, and more.

“It has been somewhat steady up and down,” said Maines. “Last year we saw 71 applications for the credit. This year, the window is from Dec. 1 to Feb. 15, and we’ve already seen 20 applications, so we’re on track to outpace previous participation in the program.”

In addition to simplifications in the application process, Maines said changes mean residents could get more taken off of their bills.

“One past participant, before the simplification, was getting a 3% reduction on their fee for a rain barrel,” Maines said. “We increased that to 5%. We added a measure for mature trees and a no-fertilizer pledge because fertilizer has a big impact on water quality. They went from a 3% reduction to a 30% reduction in their fee.”

Maines said it can be difficult for residents to know where to start, but the no-fertilizer pledge and installing rain barrels under downspouts are both easy paths into flood mitigation projects.

Another big boost to the credit program this year is an overlap with the Flood Mitigation Grant Program launched last year. The grant program reimburses residents for the cost of many flood mitigation projects, and with the utility credit program, those projects can also count toward getting the stormwater utility fee reduced.

“It’s a reimbursement program for up to $5,000 of floodproofing on those homes,” Maines said. “A good portion of those are now included in the stormwater utility credit program.”

The grant program was popular enough to suffer a bit of a backlog early in 2022. Maines said he’s hopeful that the two programs can help boost each other.

“If we had 71 participants last year, could we get 150 this year?” Maines said. “That’s what we’re hoping, really. There is a benefit to water quality and flooding, so we see this as money well spent. People get to reduce their fee and you raise awareness for flooding and water quality issues.”

Maines said the credit programs have been geographically pretty widespread, but with notable pockets in areas like Rosemont or Del Ray that have experienced severe funding.

The last day to apply for the stormwater utility credit is Feb. 15, and the credits are good for two years.

Meanwhile, the city is also moving forward on some of the larger capacity projects. Two major projects recently hit milestones and one of those, the project at Commonwealth Avenue and East Glebe Road/Ashby Street and East Glebe Road, saw design work start last week with a site visit.

Maines said, at the moment, there are 35 projects in the works around Alexandria, ranging from larger capacity projects to smaller ones.

In general, Maines said some of the initially hostile community reaction to the city’s flooding response has faded as work on some of the more high-profile projects has gotten underway and city staff has visited around the affected communities.

“We’ve been going out in the community, we went out to almost 20 or 19 different neighborhoods,” Maines said. “We went on-site and talked to people. We had Zoom meetings to talk about issues people had to get better detailed information. It helps that some of us are in the city and we experience flooding as well, we have to have that empathy to know what people are going through, and letting them know that we are committed to these projects and council is supporting us.”

More information on the credit program, including a step-by-step application guide, is available at the city’s website.

Photo via DrainALX/Twitter

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Engineers from Jacobs Engineering on a site visit for a stormwater capacity project in Del Ray (courtesy City of Alexandria)

If you saw workers in bright vests around Del Ray last month, they were engineers contracted with the city, and their presence marked the start of design work for a major stormwater capacity project.

The project has the unwieldy name “Commonwealth Avenue and East Glebe Road and Ashby Street and East Glebe Road” after several smaller projects were smushed together.

The goal is to boost the size of the stormwater sewer pipes in Del Ray, meaning that the pipes can hold more water and it will take longer for them to flood.

According to the city’s website:

In the Four Mile Run watershed, the two top priority projects Commonwealth Avenue & E. Glebe Road project and E. Glebe Road and Ashby project are being combined under one large capacity project because they are located next to one another. This project is expected to increase the capacity, or size, of the stormwater sewer pipes; create opportunities for stormwater to be stored and released slowly over time; and incorporate ‘green infrastructure’ practices, such as permeable pavement, that allow the stormwater to soak into the ground, reducing runoff.

A contract was awarded for the project design in October. A city newsletter called Flood Action Alexandria said the project made headway last month as engineers conducted a site visit as part of the initial design work.

“The site visit will be followed by other preliminary work, including land surveys, geotechnical boring investigations and detailed sewer shed modeling,” the newsletter said. “This supports the development of construction plans for the proposed solution.”

When completed, the project should improve stormwater conveyance and reduce some of the flooding that has plagued Del Ray in recent years.

“The combined projects are the City’s top two large capacity projects and will increase the capacity of the storm sewer system to improve stormwater conveyance,” the newsletter said. “The project will also incorporate green infrastructure elements, which will capture runoff carrying surface pollutants, providing a water quality benefit to the watershed.”

The estimated cost for the design and construction of the project is $50 million, paid for in part by a grant from the Virginia Community Flood Preparedness Fund.

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Flooding near the Braddock Road Metro on Thursday, September 16, 2021. (Courtesy Kerrin Nishimura)

The City of Alexandria is making it easier for locals who pitch in on flood prevention to skip out on their utility fees.

At a meeting last night, the City Council voted to adopt a series of changes to a utility fee credit program, including reducing the fee for residents who install flood mitigation on their property.

All property owners in Alexandria pay a stormwater utility fee based on the amount of impervious area — or hard surface — on their property. The Stormwater Utility Fee Credit Program allows local property owners to claim reductions on that fee.

Flooding has been a significant problem for Alexandria in recent years. The fee helps pay for flood mitigation projects and other parts of the stormwater management program.

Some of the changes should make is easier for locals to earn get that fee reduction.

“Property owners can earn credits to reduce the fee by installing and maintaining eligible stormwater management practices and filing an application to the City,” the city said in a release. “Applications can be submitted by searching for the property on the City’s Real Estate webpage or submitting a hardcopy form. Applications will be accepted from December 1 to February 15.”

According to the release, some of the changes from the meeting include:

  • Simplified application process that removes duplicate items and streamlines documentation requirements
  • Two-year credit applied to two consecutive calendar years – or four billing cycles – for approved applications for eligible practices
  • Increased credits for individual eligible practices and increased overall potential maximum credit per application from 30% to 50%
  • Previous applicants will be notified via email to reapply for the next two-year credit cycle starting in 2024
  • Added credit option for preserving and maintaining existing mature trees and dry floodproofing practices
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New manhole cover (image via City of Alexandria)

It’s a change that likely won’t go noticed by many Alexandrians, but the city is making an adjustment to its manholes that could have an impact on flooding during storms.

According to Flood Action Alexandria — an ongoing newsletter highlighting flooding issues and mitigation measures in Alexandria — the City of Alexandria is working on finding a contractor to install 870 stainless steel manhole inserts around the city.

“Manhole inserts are pan-shaped devices that sit at the top of the manhole, directly underneath the manhole cover,” the newsletter said. “They prevent stormwater inflow from gushing to the sanitary sewer after it enters the hole in the manhole cover.”

The inserts have a hole that slowly trains accumulated stormwater after the storm ends. The idea is to reduce inflow into the sanitary sewer system, which often becomes backed up during storms and contributes to flooding.

A map of where the manhole inserts will be located is shared online.

The newsletter also shared some updates on other flooding projects. The combined Commonwealth and East Glebe Road and Ashby and East Glebe Road project — which will increase the capacity of the storm sewer system — is in contract negotiations with an engineering firm ahead of moving into the design phase.

Two spot improvements, one at Oakland Terrace Timber Branch and another on Mount Vernon Avenue, are entering the construction phase.

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Thousands of art lovers will have to set aside their plans this weekend, as Del Ray’s annual Art On The Avenue has been postponed due to Tropical Storm Ian.

Ian battered Florida with intensity that is now petering out and working its way up the East Coast. For Alexandria, there is 70% likelihood of rain this Saturday, and event organizers have decided not to chance a washout.

The festival will now be held on Saturday, November 12.

This is the third year in a row that Art On The Avenue has taken a hit. The 2020 festival was virtual due to the pandemic, and last year’s event was attended by thousands of people, but an unforced power outage prompted businesses along Mount Vernon Avenue to be shut down.

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Severe thunderstorm as of 4:15 p.m.

The National Weather Service has issued both a Flash Flood Warning and Severe Thunderstorm Warning for Alexandria and surrounding localities.

“The National Weather Service has issued a Severe Thunderstorm Warning for Alexandria,” the city said in an emergency alert. “Seek indoor shelter immediately.”

In a separate Flash Flood Warning, the city said to avoid small streams and not to drive through water on roadways.

More from the National Weather Service:

BULLETIN – IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Baltimore MD/Washington DC
428 PM EDT Wed Aug 10 2022

The National Weather Service in Sterling Virginia has issued a

* Severe Thunderstorm Warning for… The northwestern District of Columbia… Southeastern Montgomery County in central Maryland… Northwestern Arlington County in northern Virginia… Northeastern Fairfax County in northern Virginia…

* Until 515 PM EDT.

* At 428 PM EDT, a severe thunderstorm was located over North Bethesda, or over Rockville, and is nearly stationary.

HAZARD…60 mph wind gusts.

SOURCE…Radar indicated.

IMPACT…Damaging winds will cause some trees and large branches to fall. This could injure those outdoors, as well as damage homes and vehicles. Roadways may become blocked by downed trees. Localized power outages are possible. Unsecured light objects may become projectiles.

* Locations impacted include… Arlington, Rockville, Bethesda, Olney, Pimmit Hills, Mclean, Howard University, American Legion Bridge, Fort Totten, Aspen Hill, Potomac, North Bethesda, North Potomac, Fairland, Tysons Corner, White Oak, Redland, Takoma Park, Great Falls and Colesville.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

For your protection move to an interior room on the lowest floor of a building.

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Flood Watch boundaries (via NWS)

The National Weather Service has issued an Areal Flood Watch for Alexandria with rain expected this afternoon and most of this weekend.

While it’s clear skies this morning, the forecast for rain comes after heavy rainfall last night.

“Avoid small streams and do not drive through water on roadways,” the City of Alexandria said in a release.

From NWS:

1020 AM EDT Fri Aug 5 2022

…FLOOD WATCH IN EFFECT FROM 3 PM EDT THIS AFTERNOON THROUGH THIS EVENING…

* WHAT…Flash flooding caused by excessive rainfall is possible. […]

* WHEN…From 3 PM EDT this afternoon through this evening.

* IMPACTS…Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS…
– Showers and thunderstorms will develop this afternoon and may last into the evening. Any thunderstorms will be capable of producing very heavy rainfall, with localized totals of two to four inches possible. Much of the rain may fall within a one to three hour period, making rapid rises in creeks and streams possible, as well as flash flooding in urban areas.
– http://www.weather.gov/safety/flood

PRECAUTIONARY/PREPAREDNESS ACTIONS…

You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued.

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Water Levels at Cameron Run on July 9 (image via City of Alexandria)

A storm that postponed the city’s birthday celebrations last month set a rainfall record in Alexandria according to a floodwater mitigation newsletter prepared by the city.

The Flood Action Alexandria newsletter, prepared by Flood Action Alexandria communications specialist Amanda Dolasinski, noted that a storm on July 9 set the record for rainfall recorded before 7 a.m. The newsletter said the city saw nearly 4 inches of rainfall in the northeast section of Alexandria and pushed Four Mile Run to to the 10-foot stage at Shirlington Road Bridge.

“The Four Mile Run rain gauge in the northeast part of the City recorded 3.92 inches of rain at the 24-hour mark of the July 9 storm, with most rainfall recorded before 7 a.m.” the newsletter said. “The storm was classified as a 10%- to 12%-chance-per-year storm, meaning the rainfall produced exceeded the probability with a 10% chance of being equal in any given year.”

Despite the quantity of rainfall, the newsletter said the intensity was less dramatic and the city didn’t see the same levels of severe flooding as it has in the past.

“Fortunately, the intensities were less dramatic than in past large storm events,” Brian Rahal, a civil engineer for the Stormwater Management Division, said in the newsletter. “It appears the urban flash flooding was at a minimum.”

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