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Posts about Maps


50% of DC residents live on only 20% of the land

Also, a quarter lives on just 7% of it. I made these maps to illustrate that.

Maps produced by the author. Data comes from 2014 ACS five-year estimates.

According to survey data from the Census Bureau, 50% of DC's population lives on just under 19% of its total area (bodies of water are included). In absolute terms, that's almost 315,000 people living on roughly 8,000 acres.

Zooming in even more, we see that 25% of people living in DC inhabit just 7% of its land. These residents are mostly clustered around neighborhoods like Logan Circle and Columbia Heights, where housing is dense and transit is plentiful.

For comparison, 50% of New York City's population lives on only 11% of its land area:

Do you notice anything interesting in these maps?


Get to know DCís new zoning with this map

After years of delays and extensive public input, DC's zoning board approved a new zoning code in January. It will actually take effect in September. This map helps homeowners understand how the new zoning applies to them.

The zoning update includes some key steps forward, like allowing some homeowners to rent out garages or basements where it's illegal today.

Otherwise, unless you live downtown, nothing dramatic will change. The zoning update generally doesn't change the density and form someone can build in your neighborhood. Most specific rules, like how big and what shape a "court" can be, also don't change, and you're not expected to know them all unless you're an architect or land use attorney.

But what does it mean?

The reason so little seems to be changing is because the zoning code basically consists of three parts: an administrative framework, rules for development in general, and land use rules specific to each zone district.

Most of the rewrite was reorganizing existing rules written in 1958 and patched several times over the years. That means updating the language, addressing new uses, and closing loopholes. Sure, there are some big controversial city-wide changes like permitting granny cottages in single family residential areas and reducing parking minimums.

What will likely change is the name of the zone you live in. In the old code, most zones were R (Residential) or C (Commercial); now, residential zones include the old R, RF (for residential flats, like row houses), and RA (for apartments); many commercial zones, which have long allowed residential and commercial together, are called MU (mixed-use), or D for downtown zones, and so on.

This table shows how the existing zone districts fit into the new zones. The interactive map (image at the top of the post) lets you compare old and new zoning side by side.

There are a lot more zone districts now—sort of. Some neighborhoods (like Cleveland Park) have "overlays" that customize their zones. Many changed the underlying zoning dramatically, which wasn't readily understandable without flipping back and forth between sections.

In the new code, instead of overlays, there is just a new basic zone with all the rules from the underlying zone or the overlay. For example, the old R-1-B zone with the Foxhall and Tree and Slope overlay (for areas near the Potomac river on the west side of DC) will be R-9. The R-1-B zone with Naval Observatory overlay will be R-12.

The actual effect of the overlays remains, but you don't have to reconcile two totally different sections of zoning code to figure out what's going on. I think it's a lot simpler to understand, whether you're designing a building or imagining what your neighborhood could look like.


This map shows how easy it is to take transit to work

We spend a lot of time praising neighborhood walkability and proximity to transit. But how valuable is the ability to walk to the grocery store if residents still need to drive a long distance to get to work?

A map of "Opportunity Score" values from Redfin for the DC area, with county boundaries added by the contributor. Scores are based on the number of jobs paying $40,000/year or more accessible by a transit commute of less than half an hour from a given point.

The real-estate company Redfin recently released an online tool called "Opportunity Score" that lets you explore the number of jobs that are accessible by transit from any address in a number of metro areas, including DC.

For any address in an area that the tool covers, the tool can calculate a numerical score between zero (least transit-accessible jobs) and one hundred (most transit accessible jobs). Alternatively, by searching for a metro area without a specific address, you can see a color-coded map of the numerical scores throughout the region, where green corresponds to the highest scores and red to the lowest.

The Transit Score map for the DC area reveals some interesting, if not entirely surprising, patterns. Thanks to Metro and good bus service, nearly everywhere within DC, Arlington, and Alexandria has good transit access to jobs.

Some places farther out are similar: several areas in Fairfax County (particularly in the vicinities of Tysons and Reston) and a large part of Montgomery County (in Silver Spring and along the Wisconsin Avenue-Rockville Pike corridor) have very good access to jobs.

In Prince George's County, however, things are quite different. The relative lack of high-paying jobs in the county and the low density around most of its Metro stations, along with more limited bus service, result in there being very few areas in the county where it is possible to commute to many jobs by transit in under thirty minutes.

Notably, the Prince George's County section of the Purple Line will connect a number of areas with low access to jobs to the employment centers in Bethesda and Silver Spring. However, this will serve only a very small portion of the county. Better bus service as well as increasing density in the more transit-accessible parts of the county are also essential to scaling back the car-dependence of commutes in Prince George's.

The tool might not be as useful for some as it is others

It is worth noting that Opportunity Score, which is based on Redfin's Walk Score tool, has a couple of notable limitations. The list of jobs only includes ones that pay over $40,000/year, so it doesn't tell you anything about the commutes to low-paying jobs (and people with those jobs are particularly likely to use transit).

It also considers some commuting options that only run at rush hour (i.e., I could take the Camden Line from my apartment in College Park, but it only runs at rush hour, so it doesn't do me much good if I have a night shift job, for example).

Most jobs that pay over $40,000 do follow the usual 9-to-5, though, so the fact that some of the transit considered is rush-hour-only will matter less to people looking for those jobs than to service workers looking for lower-paying jobs, but who will need to commute at less standard hours.


In 1979, was your neighborhood "sound" or "distressed"?

DC looked very different in 1979. A map of neighborhood housing conditions shows just how much. In many DC neighborhoods that are now in high demand, the housing stock was in danger 35 years ago.

Image from the DC Public Library, Special Collections. Click for larger version.

This map is from a report by the Department of Housing and Community Development in June 1979, during Marion Barry's first mayoral term, entitled "Housing Problems, Conditions & Trends in the District of Columbia."

The report sounded the alarm for "Petworth, Parkview, Columbia Heights, LeDroit Park, Bloomingdale, Eckington, Edgewood and most of the neighborhoods east of the Anacostia River." Those areas already had, or were in danger of developing, "deteriorating building conditions because resident incomes are not keeping pace with increasing costs of home ownership."

Here is the explanatory text and key for the map:

This map clarifies neighborhoods according to the categories shown in the legend. They are based on the following factors which are illustrated in subsequent maps: ownership patterns, yearly income of residents, real estate sales and prices, welfare assistance and the condition of housing.

Sound [Yellow]: Residents in these neighborhoods have high enough incomes to maintain their properties without public assistance. Northwest areas west of Rock Creek Park are classified as sound neighborhoods together with Capitol Hill. The only sound neighborhoods east of the Anacostia River are located south of Fort Dupont Park.

Distressed [Blue]: Residents require considerable assistance because of low incomes and poor housing conditions. Many of these areas also contain a concentration of public housing in need of significant improvement. Distressed neighborhoods west of the river include Ivy City and portions of the Southwest. East of the Anacostia River, the poorest housing conditions are found in Deanwood, Burrville, Northeast Boundary, Greenway, Anacostia, Congress Heights, Washington Highlands and Douglass.

Stable / Declining [Green]: Neighborhoods are in stable condition, with households of moderate income and high ownership, requiring little or no public assistance; or, are beginning to show deteriorating building conditions because resident incomes are not keeping pace with increasing costs of home ownership. West of the River, neighborhoods in this category are south Petworth, Parkview, Columbia Heights, LeDroit Park, Bloomingdale, Eckington, Edgewood and most of the neighborhoods east of the Anacostia River.

Transitional (early or advanced) [Red]: Neighborhoods in the early stages of transition are characterized by a surge in reinvestment and rehabilitation; whereas, neighborhoods in the most advanced stages are those experiencing extensive displacement of low and moderate income families by higher income households. Change began in Dupont Circle and Adams Morgan and spread east into Shaw and north along 14th Street, as well as into LeDroit Park and Eckington. The change which began in Capitol Hill spread further east into Lincoln Park, south to the Southeast, and north to the Stanton Park. No radical changes are occurring east of the River, though real estate activity is becoming significant but at a lower level of intensity.

This map further serves to highlight the different characteristics between areas east and west of the Anacostia River. West of the River and west of Rock Creek Park, neighborhoods are in basically sound and stable condition. The most concentrated real estate activity is found in and around the central city. Displacement is, therefore, the major problem west of the River; whereas the main concern east of the Anacostia River is the declining condition of the housing stock. Also, the majority of distressed and declining neighborhoods are found east of the River.

It's also interesting to look at the neighborhood names. NoMA didn't exist; it was "NE 1," adjacent to "NW 1" across North Capitol Street. What we now call U Street is "Westminster." And "Stanton Park" extended all the way across H Street. East of the River, neighborhood names such as "Good Hope," "Buena Vista," and "Douglass" have fallen out of currency.

The Green and Yellow Metrorail lines had not yet opened, the Red Line didn't go beyond Dupont Circle, and the Blue Line stopped at Stadium-Armory.

What else do you notice? How was your neighborhood categorized in 1979? Would it be categorized differently today?

This post first ran in 2014. Since the history hasn't changed, we thought we'd share it with you again!


What's wrong with this map of DC's social services?

This map shows where DC's halfway houses, drug treatment centers, and mental health facilities are. What's wrong with this picture?

Map from DC's Office of Planning.

In 2006, DC's Office of Planning published this map of group homes in the city,grouping them into five types: halfway homes and facilities for community residence, mental health, substance abuse and youth rehab.

The easiest, clearest takeaway: most of these places are east of Rock Creek Park. The map may be 10 years old, but that's just evidence that neighborhoods in that part of the District have historically opted out of helping to solve the city's broader problems.

We actually came across the map while reviewing DC's Comp Plan. Let's hope the re-write of the plan, which which the Office of Planning will start next year, results in maps that show more people doing their part to make this a better region for everyone.


If Metrobus asked me to redesign its info brochures, I'd make them look like this

I've lived in DC and used Metrobus here for 14 years. I'm also a designer, and I have a few ideas about how to make the bus timetable brochures clearer for people using them to understand the system.

Metrobus brochures could included a map like this to give riders a sense of where they are even if they've never heard of the specific places.

Some of the brochures' most important information, like where bus lines run and which bus stops have Metrorail stations nearby, isn't shown at all. And if you aren't familiar with the bus line numbers or street names, you won't have the context you need.

Mockup from the author based on the original Metrobus brochure.

While many people have smartphones to get their information in other ways or know what apps to download, visitors to the city often don't. And many low income travelers either don't have a smart phone nor money for data plans.

Here's my new design:

I designed a new brochure that I think would help readers know where they are even if they don't understand the geography of the District.

Redesigned Metrobus brochure by the author.

In short, I think Metrobus brochures should give users a visual understanding of where they are rather than assume riders know street or neighborhood names and that they should provide further information on how they can connect with Metrorail.

Do you see any other ways to make my new brochure better? If you have ideas, post them in the comments!


Help us map out DC's vacant buildings

DC doesn't have an accurate count of how many vacant buildings it has, which means lots of missed opportunities for more tax revenue or new housing. We've created a map of the vacants the city knows about. Tell us about the ones that are missing, and we'll send the full list to the DC Council before it votes on a law to fix the counting problem.

Photo by NCinDC on Flickr.

We've written about problems with DC's system of accounting for vacant buildings and enforcing the regulations aimed at them a couple times over the past few months. It's a mess of loopholes where owners can skirt detection and penalties by doing things like applying for work permits but not doing any actual work for years.

In a place like DC, where space for new housing is at such a premium, this is infuriating.

DC's Department of Consumer and Regulatory Affairs publishes lists every year showing which properties it has officially designated vacant and blighted (which means a building is a threat to health and safety). When a building goes on the list, its owner has to pay higher tax rates of 5% for vacant buildings and 10% for blighted.

While the agency's count is far from complete (which is a significant part of the problem), we thought we'd start by mapping out what it has provided:

Map by Thad Kerosky (@thadk).

Remember, these are not "For Lease" buildings, vacant lots, or buildings under construction. These are buildings that 1) have no occupants, and 2) have an owner who is not actively pursuing construction or new tenants.

DCRA most often investigates a building after receiving a report from a neighbor or agency, though many people will tell you they have filed reports repeatedly with little reaction from the agency.

Get out your red pens... we can correct this!

On Thursday, July 14th, the DC Council's Committee on Business, Consumer, and Regulatory Affairs is having a hearing on a series of bills that would fix many of the problems with DCRA's current system. Greater Greater Washington would love to submit testimony in support of that legislation, but we need your help.

If you know of or suspect a vacant building nearby, use the search function above to see if DCRA has already classified it as such. If it hasn't, fill out the form below and help us collect further evidence that this system needs fixing.


Capital Bikeshare members ride here, bike lanes or not

Over half of the miles that Capital Bikeshare members ride are on streets without any sort of bike lanes. This map shows you which of those streets are the most popular:

Heat map of where Cabi members ride when there aren't bike lanes. Image from Mobility Lab.

Jon Wergin, of Arlington's Mobility Lab, put together the map after checking out data from GPS trackers on a number of CaBi Bikes, which showed what specific routes riders actually took between taking and returning a bike.

Wergin then separated data from riders who were regular CaBi members and those who were casual, less frequent users. Wergin's map focuses on the regular users, as the more casual ones overwhelmingly stuck to off-road paths close to the Mall and Monuments.

Only about 10% of DC's roadways have some sort of cycling infrastructure, but those routes still got about 1/3 of the bike traffic from regular CaBi members. Even more frequently, though, regular riders took the most direct route possible, which is why the long state avenues seem to have some of heaviest usage. Thick bands dominate Massachussetts, Florida, Louisiana, and Pennsylvania Avenues. M Street in Georgetown, K street near NOMA, and 14th in Columbia Heights also see heavy usage.

Some of these streets are due for new bike infrastructure in the next few years. Louisiana Avenue is slated for protected lanes that would connect existing protected lanes on Pennsylvania Avenue and First Street NE, and new bike lanes might also go in west of the White House.

But plans for Massachussetts and Florida Avenues are more vague. This map shows that DDOT may want to think about more specific plans for these and other roads since they're proving popular with cyclists, even without bike lanes.

What do you notice about the map? Tell us in the comments.


Maps of late night bus service are nice, but effective late night bus service would be even better

With Metro's weekend service now stopping at midnight, many will turn to buses for their late night transportation. PlanItMetro recent posted maps of all the bus service that's available in our region after midnight. They're a great step toward giving riders the information they need, but they also highlight some of the ways our night bus network falls short.

Our region's bus service between midnight and 1 am. Maps from WMATA.

There are three maps in all: One showing service from midnight to 1 am, one from 1 to 2 am, and one from 2 to 3. On top of Metrobus, the maps show routes offered by Arlington's ART, Montgomery County's Ride On, the DC Circulator, and the Fairfax Connector.

How thick a route is on the map indicates how long the wait between buses should be, with the thickest lines meaning the headway should be less than 20 minutes.

Service between 1 and 2 am.

PlanItMetro notes that the maps are missing some existing routes, like the Z8, which is a major line in Montgomery County; the maps should be updated soon. The maps also include some routes with such low frequency (once an hour or less) that it's debatable whether they're useful at all.

Most importantly, though, there's very little late night service after 1 am aside from what WMATA offers (other than some Fairfax Connector service), and most of that is designed to feed into or out of the Metro system—which isn't running past 12 anymore.

Service between 2 and 3 am.

Two of the most frequent routes between 2 and 3 AM (running every half hour) are the 16E and 82. However, the 16E is completely unconnected to DC, running only from Metro stations in Alexandria and Arlington west to Annandale. When the Metro is shut down, this route is a lot less useful—though at least it does connect with some other bus routes.

Even worse is the 82: it runs between Rhode Island Avenue Metro station and Mount Rainier, but without the Metro there is no way to reach this route via transit.

Compiling these routes is an important first step toward providing solid late night bus service, and it highlights where the network could get a lot better. Hopefully the maps can be improved, made more user-friendly, and placed on the WMATA website for riders to access them more easily.

And ideally, we can then start to take concrete steps to fill in the significant gaps in the area's night bus network.


Use this map to make Fairfax more bike-friendly

Little River Turnpike, a major road that runs across Fairfax, is difficult to bike along. The county is looking to change that, though, and a new interactive map lets you make suggestions for how it can.

Click this map for a version that you can comment on. Image from Fairfax County.

Stretching from Fairfax City to Alexandria, Little River Turnpike has been a major road since the 1800s and its interchanges with both 495 and 395 mean the road sees a lot of traffic today.

Right now, there are no bike lanes on Little River Turnpike, and sidewalks are hit and miss. Fairfax wants to make it easy to bike between the many neighborhoods and businesses up and down the road.

Riding a bike here could be a whole lot easier. Image from Google Maps.

While there is a master bike plan for Fairfax, some of its roads need a more detailed and focused approach. Little River Turnpike is one of them (the county has deemed it a "policy road"), so planners in Fairfax are conducting the Little River Turnpike Bicycle Study to determine the best way to improve bike riding options there. They're starting with the interactive map above.

One challenge for bike projects along the road is a narrow right of way, which means there isn't much space for bike lanes (and it'd be expensive for the county to buy the space). Also, there some places along the road do have ample space for a stretch, but then it ends abruptly.

The hope with the map is that planners will be able to identify quick fixes in some of the road's trouble spots. The entire study could lead to broader-sweeping changes, but those would be further down the line.

This isn't the only bicycle project coming to Annandale. A number of bike lanes will go in when Ravensworth Road, Guinea Road, John Marr Drive, and Heritage Drive get repaved this summer (all of these roads connect to or run near Little River Turnpike).

Fairfax did this last year as well, when it used an interactive map to crowdsource ideas for bike projects across the county.

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