Achieving sustainability in any development project requires more than just assembling and incorporating a set of green products. It takes planning. It takes integrated design.

As Steven Kellenberg, explained in his article in the June issue of Sustainable Land Development Today (“Integrated Planning: The Key to Developing Sustainable Planned Communities”), integrated design is “a strategy that interlinks and balances a project’s context, ecology, site planning, infrastructure, landscape and building design into a form that in totality exceeds the performance of its individual components.” In other words, the sustainable whole should add up to more than the sum of its green parts.

It is essential to identify and leverage interconnections and interdependencies in every project. This integrated approach to project planning ensures the sustainability of developments and reduces the costs of going green. Managing the costs of green building in the context of total project budgets is critical. Green has to make economic sense in order to fully transition into the mainstream.

The cost-effective and environmentally-friendly use of recycled content in lieu of virgin resources is a prime example of how innovative, “green” products can be a part of a greater, sustainable whole.

The big picture
Integrated planning for any particular development project must be local. It has to focus in on the immediate context of every specific site.

When developers, architects, builders and contractors consider green technologies and materials for a site, they should, as Kellenberg outlined, assess how their choices will complement and amplify each other in order to support the overall sustainability of the project. But it is equally important to consider the bigger picture, and the biggest picture is global. Within the context of integrated planning at the local level, we should keep in view how specific green choices contribute to addressing global environmental issues.

Consider cement. Its production is energy-intensive and releases vast amounts of carbon dioxide, the primary cause global warming. In fact, the world’s cement plants generate about five percent of all global emissions of carbon dioxide annually. Cement manufacturers are investing in cleaner production processes. However, available technologies can only reduce cement plants’ greenhouse gas emissions by an estimated 20 percent. Even with the best possible improvements foreseeable in the near term, each ton of cement produced will still generate more than 600 pounds of carbon dioxide.

Worldwide demand for cement products continues to increase, particularly in fast-growing emerging economies – most especially in China.

According to The Freedonia Group, an industrial market research firm in Cleveland, Ohio, demand for cement in China has been increasing by about five percent annually. It will top one billion metric tons this year and could reach 1.3 billion metric tons in two years. China is now the world’s largest national consumer of cement and will account for 40 percent to 50 percent of global cement consumption in 2010.

Moreover, China is one of the leading cement exporters in the world, accounting for some 17 percent of the total cement trade worldwide. The United States is the largest market for Chinese cement.

There are more than 8,000 cement plants in China. As noted in a Battelle study commissioned by the World Business Council for Sustainable Development, China relies almost exclusively on coal to produce cement. The local environmental impact in China is severe, and the global impact is accelerating. The International Energy Agency (IEA) projects that China, in no small part due to cement production, will overtake the United States as the largest generator of carbon dioxide emissions in the next few years.

Of course, no individual developer can change the U.S. market for cement – no less China’s. Developers can, however, take steps to reduce their use of cement. When it makes sense to do so in the context of integrated planning for individual projects, decreasing cement use can contribute to achieving sustainability locally and supports big-picture environmental responsibility globally.

Earthy-friendly retaining walls
Cement is the primary ingredient in concrete. Approximately 500 million concrete blocks are sold annually for segmental retaining walls (SRWs) in North America. Using an earth-friendly alternative in retaining wall construction is one option for developers to consider for decreasing the use of concrete.

Millenia Wall Solutions uses 100 percent recycled, pre-consumer polymeric resin materials in its retaining wall system. These materials are inert and do not interact with the soil. Therefore, there is no absorption from surrounding soils and no leaching into them.

An independent Life Cycle Assessment (LCA) undertaken by Terrafore, Inc., Riverside, California concluded that when used instead of concrete blocks, Millenia’s lightweight polymer wall units provide a 55 percent reduction in overall environmental impact, including a 65 percent reduction in associated greenhouse gas emissions. Based on the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) Green Building Rating System, using these walls units in construction applications can earn up to eight LEED credit points.

Solve site problems – and go green
Sustainability was not top of mind when Bill Jackson first thought about using Millenia to replace a deteriorating timber retaining wall for a homeowner in a southern suburb of Minneapolis. Jackson, owner of Jackson Landscape Supply (Lakeville, Minnesota) had a more immediate problem: difficult access on a steep site.

The property slopes up from the street. There is only ten feet from the back of the house to a six-foot-high rock wall and embankment. The retaining wall site itself is above the rock wall, and the area varies in width from four to eight feet.

“I wondered how we would get conventional retaining wall materials to the back of the house and up to the wall site without breaking our backs,” said Jackson. “So, I initially thought about Millenia because its lightweight units would be easier to get up on the site and install there.”

Jackson recommended this alternative to the homeowner and showed her how the product would complement the lower rock wall.

“When I told her that it is a green product, she was very enthusiastic,” said Jackson. “In addition, by using Millenia we could do less extensive excavation, and that saved three trees behind the retaining wall that the homeowner did not want to lose.”

The finished retaining wall is 100 feet long and 6.5 feet high at its tallest. From the time that the old timber wall was demolished and removed and the site was prepared, Jackson’s four-man crew installed the new wall in just three days. He estimates that it would have taken at least six days to construct it if he had used stones or concrete blocks. That would have increased the costs of the project for the homeowner.

“We didn’t have to haul and lift heavy rocks or blocks. The Millenia units only weigh five pounds each, so we tossed them up to the guys,” said Jackson. “After we locked them into place, we filled them with crushed stone to add weight to the wall.”

“It looks great and blends in nicely with the rock wall. Each style of the product is delivered with five different patterns on the faces so the wall has nice ­variations in texture and fine ­detail.”

No magic green bullets
There are no magic green bullets to achieve sustainability. No one product or technology is sufficient in and of itself. As noted, an integrated approach to project planning is required to maximize the impact of the green practices and materials selected for a project.

Sustainable development plans often include retaining walls as an element of erosion control and storm water management. When retaining walls are required, it makes good sense to use an earth-friendly alternative – especially one that meets a project’s aesthetic and cost requirements. SLDT