With New Mobility, Design Is Even More Important

Escooter rider / Wikipedia, Alex Genz, CC BY-SA 4.0

“New forms of mobility, autonomous vehicles (AVs), and e-commerce will impact everything we care about in cities,” said Nico Larco, professor of architecture at the University of Oregon and director of the Urbanism Next center, at an event at the American Society of Landscape Architects (ASLA)’s Center for Landscape Architecture in Washington, D.C.

The event, which was held during the Transportation Research Board (TRB)’s annual meeting, was moderated by ASLA President Wendy Miller, FASLA, who is also a member of TRB’s AFB40 committee on landscape and environmental design.

Technology-enabled transportation systems have scaled up at an incredible rate. There will be even more rapid change coming, along with new forms of transportation not yet envisioned. The coming changes make smart street design that can create equitable access to multiple forms of personal mobility even more important.

A few examples of the shifts underway:

“There were 4.2 billion trips with Uber and Lyft in 2018; ten years ago, these companies didn’t exist,” Larco said.

In many cities, e-scooters essentially started in 2018 and, by the end of the same year, they accounted for some 38 million trips. “It took bike share systems nine years to reach the same number of trips.”

“Waymo is now testing driver less vehicles with select families in Arizona.” The company, which was formerly known as Google’s driverless vehicle company, has already purchased 82,000 vehicles from a Detroit manufacturing center that turns conventional vehicles into autonomous ones. “Waymo will run these AVs as part of their fleet.” (A recent Brookings Institution survey found that 61 percent of Americans are not inclined to ride in self-driving vehicles).

Waymo driverless vehicle / Wikipedia, Grendelkhan, CC BY-SA 4.0

E-commerce has increased to 14 percent of total retail sales in the U.S. In contrast, the number of walk-ins to brick and mortar stores has fallen 6-9 percent each year, and last year saw the largest number of store chains closing yet.

In 2018, some 15 billion packages were delivered in the U.S., which equals 118 packages per household, or one every three days. As the number of delivery packages continues to increase, what does that mean for malls and downtowns?

There are some 1-2 billion parking spaces in the U.S. The rise of Uber, Lyft, and other rideshare and carsharing services, which only need pick-up and drop off zones, will reduce the need for parking. And “when we have fully autonomous vehicles, the need for parking could be reduced by 80 percent.”

Typical suburban mall parking lot. Puente Hills Mall / Wikipedia Commons, Public Domain

By reducing parking spaces, AVs could then generate demand for denser nodes in suburbia, create opportunities for urban infill in cities, and result in new parks and open space.

Furthermore, both commercial and residential buildings would no longer need to “carry the cost” of parking spaces. “Housing subsidizes parking, which means parking also increases the cost of housing.”

Without the need for parking spaces, the available land supply could also increase, and the price of land, particularly in suburbia and exurbia, could drop. So the net result of fleets of roving AVs could mean more vacant land, reduced property taxes, and lower revenues for communities — that is unless the AVs themselves are taxed.

Larco foresees considerable debate over curbside access fees for future rideshare, carshare, and AV services. Imagine crowded pick-up and drop-off areas in downtowns. How will access be guaranteed or prioritized? State and local governments will play an important role in deciding fees, perhaps by location, distance from popular destinations, or time.

With an increasing number of personalized modes of transportation competing for street space, a central challenge will be how to organize streets. If poorly planned, e-commerce delivery boxes will litter sidewalks, AVs could stop in bicycle / e-scooter lanes, and public transit could get squeezed out. “The new streets are a huge opportunity to show the importance of design.”

Furthermore, given transportation options will be more plentiful and ordering online will be even easier, location may be less important. The question that will increasingly matter is: “Where will you spend your time? Quality design is a magnet, so design will matter even more.”

(Learn more at Urbanism Next’s new hub called The Nexus, which explores the potential issues and impacts of new mobility).

For Sakina Khan, deputy director at the Washington, D.C. office of planning, AVs and other new transportation technologies pose new challenges as the capital city moves towards achieving “livability, equity, and safety,” which are the goals D.C. residents identified through surveys as the most important.

An update of the transportation, land use, and urban design portions of the Washington, D.C. 1,600-page comprehensive master plan is currently underway. As part of the process, D.C. is seeking to create more a more equitable transportation system, with multi-modal transit-oriented developments (TODs), traffic-calming measures to reduce traffic fatalities and accidents and achieve Vision Zero, and “transportation equity pilots” in the lower-income Wards 7 and 8.

Khan said D.C. has moved away from “vehicle carrying capacity” in their analysis of streets towards “person carrying capacity.” This reflects the increasing focus on personalized mobility options like e-scooters.

She discussed how critical access to transportation is to achieving a healthier population in D.C. Policymakers in the district are increasingly looking towards the “non-clinical social determinants of health, which account for 80 percent of health outcomes.” Non-clinical determinants of health could include access to good food, jobs, green spaces, and healthcare within walking distance.

In Ward 7 and 8, the city seeks to increase access to Metro through a subsidized taxi to rails program along with “heavy subsidies” for Capital Bikeshare, taking the subscription rate down from $85 a year to just $5 for low-income residents that qualify. The goal is to improve equitable transportation access and therefore health outcomes in some of the poorest neighborhoods.

Capital bikeshare / Wikipedia, Mariordo (Mario Roberto Durán Ortiz), CC BY-SA 3.0

As far as AVs, the city will incentive the use of shared rides instead of “zero or single rides.” Zero rides sounds fantastical, but fleets of AVs could roam the streets, waiting for rides, causing congestion. “AVs needs to be supplemental to transit, bicycle, and pedestrian networks — not a replacement.” The city is working with AV companies to map the entire district. But for Khan, it’s still unclear whether AVs will lead to infill or sprawl, and how they will impact jobs.

Ken Ray, ASLA, deputy director of landscape architecture at Toole Design, based in Silver Spring, Maryland, which has developed innovative multi-modal transportation systems like Jackson Street in Saint Paul, Minnesota, argued that as modes change — for example, from docked bike share to dockless bikes and e-scooters — the fight for access is increasingly happening at sidewalks, the curb, and in bicycle lanes.

Jackson Street Reconstruction, Saint Paul, Minnesota / Toole Design

To figure out a way forward, the city of Boston, which recently released its Go Boston 2030 transportation plan, is piloting micro-mobility hubs in eight neighborhoods. Toole Design is working with city’s new mobility team, other agencies, and neighborhood groups to plan, design and implement the new hubs. According to Ray, these projects are the “first-of-its-kind at filling last-mile gaps in Boston’s transportation network by co-locating transportation mode choices.”

Micro-mobility hub / Toole Design Group
Micro-mobility hub / Toole Design Group

Designing for a few modes of transit is fairly straightforward, but “if you have to layer everything, including package delivery, AVs, pedestrians, bicyclists, vehicles, and app-enabled transportation systems, the street fills up quickly.”

Ray sees these hubs as potential models for balancing modes if they can also broaden access for users in an equitable way. He described work Toole Design has done to create “neighborhood mobility stations, where dockless bikes and e-scooters could be gathered and made available in centralized locations.” With geo-fencing, it’s possible to incentivize app-based transportation providers to drop off e-scooters in specific locations.

But he also cautioned that more work needs to be done to reach urban populations who are low-income or don’t have a credit card or smart phone and therefore can’t access app-driven forms of transportation. To be truly equitable, these systems need to provide other options as well.

In San Francisco, Toole Design is working with SPIN, a dockless bike provider, to redesign an equitable access program required by the city government to “lower barriers to entry.” The approach requires them to sign up one “access user” for every five scooters deployed. One issue is that SPIN had a “burden of proof” issue, forcing potential users to “jump through hoops, which is a huge barrier to sign-ups.” The redesign project aims to increase the number of SPIN access users by redesigning access points to make the process much easier.

SPIN equitable access hub / Toole Design

In the Q&A, Larco said state and local governments need to work with technology companies through collaborative pilots that can help undo the combative relationship companies like Uber have had with cities.

Miller and Ray also made an argument for using design, prototypes, and pilots to find solutions to complex street design challenges.

Ray said “things are changing so fast that policy can’t keep up. It’s important for policymakers to set goals and principles but allow landscape architects flexibility in meeting goals where possible.”

Khan argued that future transportation infrastructure design must be “start with people first.” This will help reduce the “huge disconnect between how we live and the infrastructure we have now.” Key goals include “sustainability, resilience, equity, and economic opportunity.”

Larco believes that “urban planners are looking ahead to the issues that AVs and other technologies will bring. Developers are just starting to, but architects and landscape architects are still far behind.”

In an 100 percent AV future, space freed up by the reduced need for parking could be transformed into green spaces, making cities more livable and healthy. But with this AV future, which would create demand for narrower lanes moving vehicles faster, there could also be “pressure to add more lanes,” said Larco.

“It will be hard to fight against the economic potential of AVs and focus on the ecological potential.” There will be increased demand to “cram as much as possible into spaces,” but it’s important to remember the economic, social, and health benefits of nearby green spaces. “One urban park can raise the value of the entire block.”

Interview with Meg Calkins: The Case for Sustainable Landscape Materials

Meg Calkins, FASLA

Meg Calkins, FASLA, is the department head and professor of landscape architecture at North Carolina State University. She is a contributing editor to Landscape Architecture Magazine, a founding member of the Sustainable SITES Initiative® (SITES®), and author of Materials for Sustainable Sites: A Complete Guide to the Selection, Evaluation and Use of Sustainable Construction Materials and The Sustainable Sites Handbook: A Complete Guide to the Principles, Strategies and Best Practices for Sustainable Landscapes.

Interview conducted at the ASLA 2019 Conference on Landscape Architecture in San Diego.

Over the past few decades, how much progress have we made towards achieving sustainable landscapes? What practices promoted through the Sustainable SITES Initiative® (SITES®) have landscape architects now widely adopted? What low-impact material alternatives do landscape architects now widely use?

In general, we have made strong progress toward sustainable landscapes in some areas. Green infrastructure — including bioretention, bioswales, rain gardens, even green roofs — are now pretty widely used, especially in urban environments. Their performance and cost benefits are well-documented.

Landscape architects are getting a handle on how to employ them in a functional and artful way. Landscape architects are also starting to speak the language of civil engineers and doing great collaborations in the area of stormwater management. This whole area of SITES and sustainable site design has been really successful.

ASLA 2019 Professional General Design Honor Award. Chulalongkorn University Centenary Park, Bangkok, Thailand / LANDPROCESS

Landscape architects are also designing with native plants and plant communities in mind, and many are avoiding invasive plants. If only we could get the nursery industry to not stock invasive plants, we would be OK. But even in urban settings, landscape architects are conceiving of plant communities as habitat as well as having aesthetic value.

Where are the major gaps? Where does progress need to happen the most?

Use of materials with reduced environmental and health impacts are lagging behind. This is because clear and comparable information about the carbon footprint, resource use, manufacturing impacts, and toxicity of materials and products is not widely available.

Information transparency is perhaps the biggest challenge when trying to reduce the environmental and human health impacts of materials and products. LEED, SITES, and the Living Building Challenge offer credits encouraging information transparency, but these credits are still among the least achieved.

Product manufacturers do not provide information on embodied carbon, resource use and waste, energy and water use, and toxicity impacts. Human health impacts may be the most challenging to identify given many manufacturers claim the constituents of their products are proprietary and therefore will not release information on the types of chemicals used or produced and their quantities.

The habitat and cultural impacts of raw material extraction are often an out of sight out of mind issue. For example, we don’t see the impacts of harvesting tropical hardwood lumber from the Amazon, so it doesn’t seem so problematic to use it. We don’t see the ecosystem decline after the removal of the keystone species tree that is cut to make tropical hardwood lumber. We don’t hear about the murders of indigenous people to intimidate them to leave their protected land so tropical hardwoods can be harvested. And we don’t know that there is a 78 percent chance that the tropical hardwood we are using was harvested illegally (Greenpeace 2014).

Through Climate Positive Design, Pamela Conrad, ASLA, has devised a comprehensive approach for designing and constructing landscapes so they sequester more carbon than they emit over their lifespans, transforming them into net carbon sinks. Through her design toolkit, she recommends swapping carbon-intensive materials with lower-carbon options and planting more greenhouse gas-absorbing trees and shrubs. As you just mentioned, one of the issues you have identified is the lack of third party-verified environmental product declarations with publicly accessible data. How can we get full transparency around the environmental impact of landscape products?

First, I want to say that balancing carbon onsite is a critical aim, and Conrad’s design toolkit is wonderful. It’s going to have a transformative impact on site design and material and product specifications.

Embodied carbon of materials is a far more accurate indicator of the impact of producing a building material or product than embodied energy. Embodied energy is not as accurate because all energy sources do not have equal impact on the environment. Some will be almost carbon neutral, like wind power, and others, like coal, will have very high embodied carbon and a substantial environmental footprint.

But while carbon considerations are heavily prioritized in decision making in the building fields, they do not tell the whole story. The human health impacts of materials and products, which can be very substantial, tend to fly under the radar.

PVC, a plastic that is used in countless construction products, has lower embodied carbon than some other plastics, but it can be extremely toxic to humans in manufacture, use and disposal, particularly if it is burned or heated to very high temperatures. Designers need to consider these impacts, but the only way they’re going to know about them is for manufacturers to tell us exactly what is in the products and what by products are produced.

Information transparency by product manufacturers is an area that lags behind other sustainability considerations. I did a content analysis study back in 2012 of the websites of all exhibitors at the 2012 ASLA conference. We looked at what kind of information they’re providing on the impacts of their materials and products, and the steps they’re taking to make them more sustainable. Less than 1 percent provided either life cycle assessment (LCA) or environmental product declarations (EPD).

I’m replicating that study right now, seven years later. I don’t have the results yet, but I suspect it’s going to be closer to 10 percent providing that kind of information. There is progress being made, but we still not enough information for designers to use to compare similar products.

SITES and LEED have likely had a slight transformative impact on the information that product manufacturers provide. But the fields of architecture and interior design are ahead of us. If we did a content analysis of their product websites, we would probably find somewhere between 20 and 30 percent provide environmental product declarations.

The main way to address the lack of information is for landscape architects and designers specifying site construction products to talk to product manufacturers and ask for information about the environmental and human health impacts of their products. Telling manufacturers — “Well, I’m considering using your product but your competitor, Company X, has an environmental product declaration, so I’m going to go with them” — is only way to make it happen.

Of course, one can earn LEED and SITES credits for companies that offer some material transparency. But I don’t know if that’s making change as much as designers constantly asking for that information.

Concrete production accounts for around 8 percent of global greenhouse gas emissions. Cement, which is a primary ingredient in traditional concrete, is the second-most used natural resource after water. You have written about the many low-carbon concrete options companies are developing, including carbon-sequestering concrete, concrete that requires lower amounts of energy to produce, and concrete primarily made up of fly ash and other waste products. What will it take to replace the conventional polluting concrete with these new alternatives?

These alternatives are so new that many are not widely available on the market yet. Some are still in development. But of those on the market, only the earliest adopters are specifying them. They’re better used in Europe, because many are European technologies.

In the U.S., landscape architects oftentimes don’t specify concrete mixes. Landscape architects need to convince the people who do — the engineers, the contractors and the Departments of Transportation — to do it.

Contractors are understandably nervous about using new concrete mixes and are not easily convinced to change. Durability is such a key consideration in the performance of concrete, and it is still a question with the new low carbon technologies and mixes. It’s just going to take time and experimental applications. If the applications are monitored and the data on performance published, adoption of these technologies will happen.

Solidia Technologies’ Solidia cement (low Portland Cement) and Solidia concrete (injected with carbon) was successfully tested in multiple applications by the Federal Highway Administration (FHWA) in east coast locations. This is one way that these technologies can trickle down into the site construction market. If the FHWA or U.S. Department of Transportation believes in it and has it as either a standard or alternative specification, then the contractors in that area are much more likely to want to use that product.

D.I.R.T. Studio artfully integrated recycled concrete, bricks, and rusted metal found onsite at the Urban Outfitters headquarters at the Philadelphia Navy Yard, creating a rich, layered environment that demonstrates sustainable values. Do you see this recycled landscape aesthetic becoming more popular? What trends do you see in the use of recycled materials?

The answer is both yes and no. There’s a type of project that can use reclaimed material successfully. Not all clients want that aesthetic and not all project budgets can afford it.

Some projects will never be able to incorporate reclaimed materials because of the budget and bid structure. In a public bid project where the contractor is not onboard until after the bid set is complete, there may be insurmountable obstacles to use of reclaimed materials. It is best if one can design with reclaimed materials in hand, rather than setting out to find them after the bid documents are complete. If you set out to find a nine-by-nine reclaimed cypress post for the pergola that is fully detailed, you’re never going to find it. You need to find the material first and then design with it.

Cost can also be an issue. Once located, reclaimed materials sometimes need to be stored for several months until construction. And the material may need work such as removal of nails, cleaning, resurfacing and even regrading.

I don’t want to discourage this: if it’s a landscape architect can pay this kind of attention to the reclaimed materials, that’s great, but it’s just not feasible for every project.

Concrete was broken into pieces and reused as pavers in a garden. ASLA 2014 Professional General Design Honor Award. Urban Outfitters Headquarters at the Philadelphia Navy Yard, Philadelphia, Pennsylvania / D.I.R.T. Studio
Steel from the site was reused as low walls for planters. ASLA 2014 Professional General Design Honor Award. Urban Outfitters Headquarters at the Philadelphia Navy Yard, Philadelphia, Pennsylvania / D.I.R.T. Studio

There has been a growing movement to end the extraction of Ipe and other tropical hardwoods, which is highly destructive to rainforest ecosystems. Landscape architects like yourself and Michael van Valkenburgh, FASLA, have instead promoted the use of native hardwoods like black locust. There are also composite, thermally modified, polymerized, and acetylated wood products. Help us navigate the landscape of tropical hardwood alternatives. How should landscape architects make a decision?

There is absolutely NO reason to use tropical hardwood lumber anymore. There are good alternatives that exist that perform in some cases better than tropical hardwoods and have far lower impacts to ecosystems. Ipe, Cumaru, some of the other tropical hardwoods are keystone or umbrella species in their ecosystems.

Once that one tree is removed, studies show that the forest, plants, and animals for acres around it that depended on that one tree will decline. Within five years that land is usually turned over to grazing land for cattle. Because of this fact, even selective harvesting is not a good practice for rainforest trees.

Ipe trees bloom in yellow and pink in the Brazilian rainforest / iStockPhoto.com

There are also unseen social impacts to using tropical hardwood lumber. Tropical hardwood extraction has devastating social impacts to indigenous communities. Few designers know that since 1985 there have been 1,700 deaths in the Amazon over land disputes that primarily have to do with illegal logging. Also, tropical hardwoods are not a renewable material because it takes 90 to 200 years to grow a comparable tree, but the lumber from that tree is only going to be in use for about 30 years.

There are many alternatives to tropical hardwoods now on the market. Thermally modified wood, acetylated wood, polymerized wood– all three of those use heat and either steam or acetic anhydride or a polymer cross-linking agent, furfuryl alcohol, to modify the sugars of the wood, so that decay organisms no longer recognize them as food. All three of these lumber treatments are non-toxic. They make the wood more dimensionally stable, harder, and much more competitive with the durability of tropical hardwoods. And they are easier to build with than the extremely dense tropical hardwoods.

Another alternative to tropical hardwoods is fused bamboo, which has been on the market in China for close to ten years. It’s a really hard product similar to Ipe, so it needs carbide blades to cut and drill it. It’s a very durable product, and unlike, Ipe, uses a clip system that avoids the pre-drilling and screwing necessary for Ipe boards. It is a rapidly renewable product, with rapid growth of the bamboo every three to five years.

Fused bamboo is essentially stripped, carbonized, and impregnated with phenolic resin, which may or may not have some toxicity issues. It does contain formaldehyde, but the jury’s still out on that. Anyway, it performs and weathers really well. It’s easily oiled and rejuvenated, guaranteed for 10 years in commercial applications and 30 years in residential applications.

And then of course black locust is also a good alternative. It can be challenging to use because black locust trees do not grow straight, so when you cut it into lumber, it tends to want to return to its irregular form. But it is starting to be grown on plantations and should have a straighter habit when farmed. Also, use of shorter lengths can prevent its tendency to warp.

Black locust planks make up a walkway in an atrium garden. ASLA 2006 Professional General Design Honor Award. Small is Beautiful, Millburn, New Jersey. Michael Van Valkenburgh Associates / Elizabeth Felicella

Innovative new materials in development include concrete that can absorb air pollution and clean the air, bricks that can be grown, and plants that can be engineered to produce light. What emerging material technologies are you most excited about? Which have the greatest potential to improve our built environment?

I’m the most excited a process called electrically modified cement (EMC) activation. It’s essentially a process that modifies the surface of hydraulic waste materials like fly ash and blast furnace slag, or even some natural pozzolans like silica sands and metakaolin.

The process increases the surface area of these particles, creating micro-cracks and dislocations of structure at the nano scale, allowing for greater surface area and greater reactivity with respect to the processes of cement. It’s possible to achieve a concrete with 70 percent fly ash and just 30 percent cement. Once this finds its way into the market, it’s going to really transform concrete. That said, fly ash is only around as long as we’re burning coal. In Europe, for instance, they’re burning a whole lot less coal, so fly ash is not nearly as prevalent as it is in the U.S. anymore.

The other thing I’m excited about is recycled plastic aggregate concrete (RPAC), which is in the testing and case study application phase. There’s a whole lot of waste plastic in this world and if we can find a way to use it instead of non-renewable virgin aggregates, we should. The technology is still in the research phase, but preliminary results of RPAC as fine aggregate show an increased flexural strength, tensile strength, and density. There is so much on the horizon to improve the environmental and human health footprint of concrete.

Interview with Patricia O’Donnell on Revitalizing Cultural Landscapes

Patricia O’Donnell / Heritage Landscapes, LLC

Patricia O’Donnell, FASLA, AICP, Fellow, US/ICOMOS, is founder of Heritage Landscapes LLC, Preservation Landscape Architects and Planners, winner of the ASLA 2019 Firm Award. Her works and contributions sustain and revitalize our shared commons of public historic landscapes and advance the United Nations’ Sustainable Development Goals (SDGs), 2030 Agenda, and the New Urban Agenda.

Interview conducted at the ASLA 2019 Conference on Landscape Architecture in San Diego.

Over your career, you’ve worked on more than 500 cultural landscape projects. You have highlighted Pittsburgh’s $124 million investment in revitalizing its public spaces, such as the Mid-Century Modern Mellon Square, which you restored, as a model. What does Pittsburgh know that perhaps other cities need to learn?

In the 19th century, Pittsburgh had a vision of setting aside major green spaces in order to shape the city. Neighborhoods grew up around the green spaces. Since Pittsburgh is still today a neighborhood-based city, everyone cares deeply about their green assets. Pittsburgh has a history of understanding the value of parks.

Pittsburgh looked at their historic parks and said, “This has value for the city.” The revitalization effort was initiated by the very bright Meg Cheever, a lawyer by education and a publicist by application who founded the Pittsburgh Parks Conservancy. She knew she needed to grab attention so she built up the Conservancy as a real partner to the city. She was very savvy about not having an adversarial relationship with the city, instead creating a true partnership. We’ve worked in a number of conservancies, and that coin can flip both ways. The first thing is you need to be a partner; the second thing is you have got to recognize value.

When I started my firm in the late-80s, we did a project in Gilford, Connecticut. I told them there are four groups of tools for improving the public realm: community engagement, plans or advisory tools, law or regulation, and finance. As landscape architects, we’re good at community and planning, not necessarily so good at legislation or finance. If we recognize those are the four things we need, we can figure out who to partner with and what skill sets and mindsets are needed to move forward.

Pittsburgh started with its 19th century legacy. They had three big parks: one that was gifted to the city in the early 20th century by Henry Clay Frick; Mary Shenley’s property, which the city had bought and then added to Shenley Park; and Highland Park, which was around a reservoir and then grew into a park. So each park had a different vector. Then, they focused on the Mid-Century Modern pieces: The Point and Mellon Square, which were the two iconic public spaces built in the 50s and part of the first Pittsburgh Renaissance. Those spaces became elements of a national model for urban renewal. They knocked down 25 percent of the core of the city in a 10-year period and rebuilt it.

Restored Mellon Square, Pittsburgh, originally designed by John O. Simonds / Ed Massery
Restored Mellon Square, Pittsburgh, originally designed by John O. Simonds / Jeremy Marshall

Now there’s good and bad there. There was some environmental injustice and other problems, but they also renewed the core of the city and rebranded Pittsburgh. A number of other cities followed that path of renewal. (We called it urban renewal but often it was urban destruction). But the initiative worked for Pittsburgh. They were able to lift up what was a gritty steel city where industrial workers had to bring a minimum of two shirts to work because the air quality was so bad.

Your firm, Heritage Landscapes, partnered with HOK on the restoration of the National Mall in Washington D.C. What was involved in that process?

We were asked by the National Park Service (NPS) to track the history of Mall, which they framed as from L’Enfant’s 1792 plan to the present. The NPS asked us to framed it by the plans, but the plans did not reflect what the Mall actually was. We carried out this project as part of a NEPA compliance process.

Through a mapping effort, we overlaid all the soil disturbance over time — deep subsurface, shallow subsurface, surface — in CAD and made this very fun color map that showed probably a couple of teaspoons of the Mall were not altered over time. While we met NEPA compliance, we also now had the background, understood what the design was, and how the design of the Mall evolved to what we love today.

That evolution happened because of the strength of the personality and the stature of Frederick Law Olmsted, Jr.. He served on the McMillan Commission, the Commission on Fine Arts (CFA), and what is now called the National Capital Parks and Planning Commission (NCPC). He persuaded the NPS to do the plan for the Mall. The linear quality of the green panels was key.

We focused the HOK team on getting the grading right. The Mall had been slightly domed and tipped northward because the Tiber Creek and the Washington Canal — the drainage — were to the north. The Capitol, the White House and the Smithsonian were set on three hills, and so the Mall, the space in between, was kind of mushy. The new shape of the Mall needed to respond to that topography. The original lawn panels had a vertical curve to help drainage.

The NPS wanted the new panels accessible, under a five percent grade and, if possible, under two percent. We had to balance access, sustainability, and history. In addition, the soils were as hard as concrete. And as a result, the most common plant was a small knotweed. Soil experts, James Urban, FASLA, and others, and I thought that grading it under 2 percent wouldn’t work. The lawn panels would continue not drain well and tend toward compaction. We got the NPS to go with at least 1.8 percent, but at the edges we were up at about 4 percent and then 3 percent and then domed, but tipped northward.

To reduce compaction, soil must have open air pores. The team found the best soil for defending against compaction is sandy loam. Investigations addressed whether or not there should be additives in the soil; these little crunchy things that spring back and keep the soil open. The NPS didn’t want to go down that road, so they approved a very good sandy soil mix. The first phase they decided they had a little too much organic matter. They changed it up a little bit on the second phase. We achieved what L’Enfant and Frederick Olmsted, Jr. were after: the long green corridor.

Restored National Mall, Washington, D.C. / Adam Fagen, Flickr

You just completed a cultural landscape report for Woodstock and have begun design work to reinterpret the landscape, so its story becomes more accessible to future generations. What did you unearth through your research? Where has that led your planning and design work?

The Woodstock project is a lot of fun because it’s such recent history. We developed the Cultural Landscape Report by looking at the main field where the concerts happened. We found information digging into the archive at the Museum at the Bethel Woods Center for the Arts. They had been gathering material for years, including all these low-flown, oblique aerials from a plane and ground photography.

It turned out that just barely digging into the research we found the envelope is a lot bigger. There’s the main field, Filippini Pond, where everybody went skinny dipping, and Bindy Bazaar in the woods between the main field and the hog farm where food was made. The hog farm tells the story about the commune movement. They provided the food at Woodstock, so everyone saw how a commune worked.

Hippies enjoying Filippini Pond / C. Alexander, 1969, Bethel Woods Archive

In opening up the land base envelope, we compared what we saw being used to what was actually leased to the concert organizers by the farmer Max Yasgur. The event was held on an alfalfa field, which was mown for the event. I happen to have an old alfalfa field and know what they look like. So when I saw the photos, I thought: “Oh, this is an old alfalfa field with people in Indian prints striding across it.”

There was a guy in one of the trailers who was drawing plans. He drew one plan of the Bindy Woods with the trails, so we used that to figure out that interesting area. Hippies had set up 20 something booths to sell tie dye, Indian prints, roach clips, or whatever. They put up hand-painted signs on the trees naming the paths — highway groovy path, etc.

Woodstock’s organizers planned very well for 100,000 people. They had medical officers and police; they were actually well-organized. But when the crowd hit 400,000 or 500,000, they didn’t have enough bathrooms or food.

The cultural landscape report investigation has informed where design interventions might be. The stage configuration was very interesting. The 60 by 70-foot stage was warped because of the plane of the slope of the hill. They made a turntable so they could swing the acts. When it rained, the platform wouldn’t turn anymore. They never finished the fencing but had this gorgeously shaped batwing fence.

Woodstock stage and batwing fences amid the crowds / Pinterest

We developed schematic designs of the footprint of the stage; the batwing fence; the performers’ bridge, which went over the road; and the posts at the height where the bridge occurred. We have a series of design options in front of the client that are very fun. We’ve already started to build the Bindy Bazaar paths and signs to interpret the vendors.

Bindy Bazaar paths and signs / Heritage Landscapes, LLC, Preservation Landscape Architects and Planners

What makes a successful cultural landscape report? How are these reports evolving?

When we started doing cultural landscape reports, they were called historic landscape reports. There weren’t rules. We sat on committees and helped frame cultural landscape preservation and management standards and guidelines for the National Park Service and Secretary of Interior. There are a set of steps: history, existing landscape condition, analysis of continuity and change, treatment exploration and recommendations. The goal is to find out if you are going to just preserve a landscape as-found, restore it to some earlier documented time; reconstruct missing pieces; or rehabilitate the landscape, adapting to current needs. These reports help us to suit contemporary and future needs while preserving what has been inherited.

We’re now up to over 110 cultural landscape reports or assessments. The New York Botanical Garden and Longwood Gardens really wanted the history because they sought to understand how their property had evolved. That was all they wanted. So sometimes it’s just a piece. When we worked at Dumbarton Oaks, they wanted analysis as well, so they could understand continuity and change, the evolution of the designed landscape of Mildred Bliss and Beatrix Farrand.

Bloedel Reserve asked for a heritage landscape study. They came to us and said: “We understand Prentice Bloedel’s words, but what do they mean?” And we said, “You have the artifact. We can interpret the artifact to get at the meaning.” Cultural landscape reports are customized for each place. For the second phase of analysis at Bloedel, we told them: “Okay, now you actually need to dig deeper.” They have an amazing landscape that has four character areas and 26 component landscapes. The genius of this landscape is the differentiation between the individual components, but part of the practices they were employing in their daily management were blurring those unique aspects. We helped them really hone in on the character of the moss garden versus the Japanese garden versus the woodland paths so they can manage by area.

Bloedel Reserve / Heritage Landscapes, LLC, Preservation Landscape Architects and Planners

For our work at Thomas Jefferson’s Academical Village, we made sure we researched the African American contribution to shaping the landscape. This kind of analysis depends on the place and the client, but there is a heightened sense of social justice today. That framework led us to understand whose labor actually created a place. At the Academical Village, we found the way of life for enslaved peoples did not change after the Civil War. What changed their way of life was technology. When water and sewer systems were connected to every building and lighting came, the daily life within the core of the campus shifted. These changed the back breaking labor of daily life — hauling water, chopping wood, and gardening — by enslaved peoples, who were freed at that point, but whose life and daily activities had not substantially changed from the evidence we saw on the land.

University of Virginia / Heritage Landscapes, LLC, Preservation Landscape Architects and Planners

You have said that “culture and nature are entangled and inseparable.” How did you reach that conclusion?

While we have protected areas on the planet, there isn’t place on Earth that hasn’t been influenced by humanity. We’re in an era of human influence if you look at climate change and, hopefully, our greenhouse gas draw down vectors. If we envision ourselves as a part of nature, and we see humanity as one species of many, rather than the dominant species, and we see the planet as the place where we all live, it changes our perspectives on how to proceed. Nature and culture, place and people are completely interconnected, interrelated, and interdependent.

The big issue with climate change is finding ways to draw down greenhouse gas emissions from the atmosphere. I was fascinated with Paul Hawkins’ book Drawdown, which ranked the top hundred ways to reduce emissions. Most people would think the answer would be more solar energy or carbon sequestration. But society needs to get up to speed with its needs. Actually, some of the most effective carbon reduction solutions are the empowerment of women, education for girls, and birth control for women, so we don’t overpopulate the world, and women can take a real role in the future.

You’ve been an advocate for cultural landscape preservation, equitable access to public spaces, and inclusive planning and design in international organizations such as UN-HABITAT, UNESCO, and ICOMOS. At the same time, you have also advocated for greater landscape architect participation in these organizations. How can we bridge the gap between policy bodies and the design world?

I have had rewarding engagements with peers and related professionals in working groups that build international doctrine. You gain a broadened sense of where your work can fit because the picture is expanding for you. In my opinion, all of us can benefit from global engagement — from meeting with peers face to face and engaging in committees to participating in the International Federation of Landscape Architects (IFLA), which has a very strong new policy that they passed in September on climate change, and ICOMOS, which is a curator of world heritage, the culture advisor to UNESCO World Heritage. I am constantly contributing to ICOMOS to strengthen our global heritage.

In these international bodies, I learn from others, share what I know, and the result is we all lift ourselves up together. We also bring forward emerging professionals. I’m currently the president of the ICOMOS-IFLA International Scientific Committee on cultural landscapes. We have about 212 members worldwide. We’re strengthening and coalescing our membership in Latin America to do a better job there with cultural landscapes. We’re adding a number of emerging professionals to begin to address the wealth of cultural heritage in Africa. We gain a lot by uplifting everyone, all boats rise together.