City Council to Receive Update on Flooding Mitigation at Saturday Meeting

Alexandria has experienced its fair share of flooding in recent days, and on Saturday City Council will receive an oral presentation by the Department of Transportation and Environmental Services on $750 million in water improvement projects.

On Thursday, September 10, flooding was reported throughout the city in the latest of a string of summer weather events that have shut down swaths of roadways, flooded alleyways and homes. The city sent out an advisory warning residents of “indoor sewer backups, impassable roads, power outages, and other flood-related issues.”

Nine city crews are inspecting and cleaning waterways, according to the city.

“Today’s rainfall was approximately 2.5 to 4 inches at a rate as high as 3 inches in 10 minutes,” the city said. “This was an intense, regional storm that caused widespread flooding throughout Alexandria, particularly in the eastern portion, and included storm sewer line surges and sanitary backups.”

A similar advisory was sent out after a July 23 storm, which dropped between two and three inches of rain in 30 minutes and led to flooding.

@AmyJacksonVA @justindotnet @chapman4council Not my photos/vid – my next door neighbor took these of today’s flooding in Alexandria in the alleyway and gave me permission to share them with you. pic.twitter.com/jk2K0VRLKD

— Heather § (@H_Starek) September 11, 2020

Mayor Justin Wilson said that the city is planning infrastructure improvement projects in its 10-year Capital Improvement Program.

“Today, Alexandria spends a significant amount of money on infrastructure designed to manage water,” Wilson wrote in his monthly newsletter. “In April, the City Council approved a $2.1 billion, ten-year Capital Improvement Program. Of that, over $150 million is to address stormwater and sanitary sewer infrastructure. Alexandria Renew Enterprises, the City’s sewer authority, plans another $593 million of capital investments over the next decade, primarily the RiverRenew project to remediate the Combined Sewer (sanitary and stormwater) system that serves Old Town.”

The city can currently handle a 10-year storm, but the July 8, 2019, and the July 23, 2020, storms were “more intense than this design standard, with the July 23 event about 30 times more intense,” according to the city. “Out of the 83 ‘problem areas’ in the City’s eight watersheds, the top two watersheds were Hooff’s Run and Four Mile Run, with 23 ‘problem areas’ each. More detailed planning and analysis will take place to assess the overall implementation feasibility (including construction) prior to full design of these large-scale capital projects.”

The mayor’s full message is below.

In 2011, the City’s flood zone maps were last updated, expanding the flood zones in Old Town, Rosemont and Arlandria. The expansion of these zones extended the number of property owners required to purchase policies from the Federal Emergency Management Administration’s (FEMA) National Flood Insurance Program (NFIP) as a condition of their mortgage.

Every property owner is eligible to purchase FEMA Flood Insurance. While it is only required for those in higher-risk areas, given the unpredictability of flooding, the purchase of flood insurance is recommended.

The City participates in the NFIP Community Rating System (CRS). This program allows localities to be certified based on flood plain management practices. The lower the score a community receives, the larger the discount received by property owners who purchase flood insurance. In 2013, the City became the first community in the Commonwealth of Virginia to receive a CRS score as low as 6. That entitles Alexandria property owners to a 20% discount when purchasing flood insurance, the highest discount level of any locality in Virginia.

FEMA has now undertaken a new update of the City’s flood maps. Later this month, draft flood maps for consideration will be released and there will be a process to accept community input. Once finalized, the new maps are expected to go into effect in 2022.

While flood insurance policies can help prevent financial ruin when property owners are faced with severe flood events, infrastructure (both “grey” and “green”) investment can also mitigate the impact of severe flooding events.

A climate-resilient City requires investments and potentially new policies to ensure that residents of our City do not suffer devastating damage with such frequency.

Today, Alexandria spends a significant amount of money on infrastructure designed to manage water. In April, the City Council approved a $2.1 billion, ten-year Capital Improvement Program. Of that, over $150 million is to address stormwater and sanitary sewer infrastructure. Alexandria Renew Enterprises, the City’s sewer authority, plans another $593 million of capital investments over the next decade, primarily the RiverRenew project to remediate the Combined Sewer (sanitary and stormwater) system that serves Old Town.

Together, nearly $750 million is planned for water investments. This spending dwarfs planned investments in schools, transportation and other major priorities.

The investments required in our Sanitary Sewer system are funded by maintenance fees paid by existing customers (also on the Alexandria Renew Enterprises bills) and by connection fees paid by developers.

In June of 2018, property owners in Alexandria paid a Stormwater Utility Fee for the first time ever.

The fee applies to all property owners (regardless of their taxable status). For commercial properties, it is assessed based on the impervious surfaces on the property. For residential properties, there are four tiers (apartment, townhome, small single-family home and large single-family home). There is a credit system in place to encourage actions that assist the City’s storm sewers. Essentially the fee is structured to be a user fee for the City’s stormwater handling.

The current stormwater utility fee is projected to bring in $11.3 million this year, and $200 million over the decade (assuming modest, regular increases). Those revenues will support $101 million of capital projects over the next decade, including:

• $51 million for water quality infrastructure initiatives required under our MS4 Permit
• $19.3 million for stomwater capacity improvements
• $5 million for stream and channel maintenance

Some of the specific problem areas that now have identified stormwater projects are:

• Carlisle Drive Alley
• Founders Park
• Key Drive (Unnamed Tributary channel wall)
• Lloyd’s Lane
• Loyola Street
• Oakland Terrace (Timber Branch channel wall)
• Saylor Place
• W. Alexandria Alley

The City recently completed two major stormwater projects, the Lake Cook Stormwater Management Retrofit Project and the Ben Brenman Pond Stormwater Management Retrofit Project. Both projects received funding from the Commonwealth’s Stormwater Local Assistance Fund. Completion of these projects have placed the City ahead of schedule in meeting our regulatory goals.

For over 3 decades, Alexandria has designed and planned for our storm sewer system to withstand a “10-year” storm event. A storm that is expected to have a 10% chance of happening every year, is the designed capacity of our system.

For Alexandria, a 10-year storm event constitutes one that will drop 2.28 inches of rain over a 60-minute period or 4.81 inches over a 24-hour period. This is a capacity that is at, and in many cases above, that of neighboring jurisdictions.

Putting in place the infrastructure that can support a changing climate will be a significant undertaking for our community. It will involve a large commitment of new resources and possibly property impacts.

Yet it is my belief that this work requires greater urgency to protect the property owners impacted in our City.