Location: The University of Texas at Arlington
Owner: University of Texas at Arlington
Landscape Architect: Schrickel and Rollins Associates
General Contractor: Northstar Construction
The Story: TXI’s TruGro expanded shale helps The Green at College Park achieve Sustainable Sites Certification.
University of North Texas business students were introduced to a new Business Leadership Building in the fall of 2011. At 180,000 square feet, this structure accommodates four times the number of students than the old building and contains traditional and “smart” classrooms, multimedia learning laboratories, distance learning facilities, a café, study and tutor rooms and offices for faculty and administrative staff. The project received gold-level LEED (Leadership in Energy and Environmental Design) certification which means that it met strict standards for design and construction. The landscape was one element in this certification process.
Heavy clay soils are prevalent on the UNT campus so new landscape projects focus on amending the soil. Another concern similar to most college campuses is designing the landscape for less irrigation and maintenance since these are sizeable budget costs. The 2+ acres surrounding the new building and adjacent parking structure were overly compacted during the demolition of two buildings and a parking lot. Left as they were, they would have contributed to excessive runoff and wasted irrigation dollars with inadequate air, water and pore space for the new vegetation to thrive. Consulting with the university horticulture director, the landscape architectural firm of Caye Cook & Associates established a system to rejuvenate the turf and landscape soils. The general process included:
The amended soils are a benefit to the environment. They reduce watering by allowing irrigation and rainfall to infiltrate deeper into the profile where less evaporation and drying occurs. Deeper roots are better suited to filter storm drainage and the added air and pore space contributes to less runoff and discharge into storm drainage systems. Expanded shale will improve drainage and, when combined with an organic amendment, provides a long term organic fertilizer to landscape plantings. Caye Cook & Associates designed a drip irrigation system along with a week block and mulch to hold moisture and restrict the growth of weeds. A landscape design rich in native and locally adapted plants rounded out the strategy to reduce annual irrigation and maintenance costs. A second story roof-top garden at the Leadership Building used expanded shale with washed concrete sand and compost in their large container plantings.
Expanded shale is also a favorite of landscape architects on projects with rooftop gardens, large container plantings and bio-retention areas because it is a lightweight, stable material that you only have to add once. It is weed free, pathogen free, durable and it will not float like other soil amendments. An added benefit is the ability to absorb water and slowly release it back into the soil or media as it dries out.