At the NuStar Energy campus in San Antonio, the 18-inch seatwalls/caps, terrace hardscape and gas fire pit are constructed of smooth, multicolored Oklahoma Sugarloaf flagstone. The post lamps are 42-watt compact fluorescent (CFL) lamps; the bollard-like fixtures are 32-watt CFL. The wall fa?????ade is lit with LEDS; three submersible LEDs illuminate the bottom of the pool. The depth of the lower pool averages two feet deep. There are three circulation pumps (Tsurumi 8-PN) for the constructed wetland filter and for aesthetic flow, and another pump for the lower pool. In the lower pool, shoots of "Strawberries and Cream' ribbon grass emerge from the water. This 320 cubic foot constructed wetland has a variety of lilies, bog plantings (e.g. dwarf papyrus, umbrella palm), oxygenating submerged plants (e.g., hornwort, elodea) and floating plants (e.g., water hawthorn, water snowflake).

NuStar Energy L.P. is a Fortune 500 company based in San Antonio. The water feature at the company's new corporate office was designed for the enjoyment of employees and visitors to the site, as well as an aquatic wildlife habitat.

The Design
The vision for the overall project was to provide a refined Hill Country corporate retreat. "Hill Country" applies to central Texas, which includes northern San Antonio and Austin. Hill Country terrain is limestone or granite with thin topsoil.

The sound of falling water intensifies with each descending step, as the water appears to cut through the hillside, exposing the stratified limestone. The rapids run over 90 feet, with a 12-foot drop overall, interspersed with five terraced pools. The Meadow has a view of the mass of native plants salvaged from the site: yucca, sotol and nolina.

It is home to yucca, prickly pear cactus, cedar shurbs and Texas live oak. This is arid country, and when it rains, of course, flash flooding occurs. Heavy rains on May 25 incited flash flooding that drowned three people and required the rescuing of 230 others.

The NuStar landscape conveys a beautiful and sustainable look, while preserving and enhancing existing habitat. The buildings (Phase I and Phase II) were aligned and positioned the on the site to more sensitively respond to the contours and thereby better balance the overall cut and fill. This afforded the opportunity to provide a generously wide central space between the two buildings with the creation of the "scenic canyon" and a cascading water feature. To provide and maintain a balanced aquatic ecosystem, filtration is facilitated through a constructed wetland. To reduce the use of potable water, an HVAC condensation and onsite reclamation system was installed to supply a 28,000-gallon fishpond. A rain catchment system was constructed to provide a 42,000-gallon annual storage capacity of rainwater.

The Meadow and Scenic Canyon encompass approximately one acre of a 35-acre property being developed in two phases. Within the central space between the new building and yet constructed building, the major opportunity was the overall 28-foot elevation drop across the topography from the constructed wetland to the lower pool at the outdoor terrace.

The single constructed wetland provides biological filtration for the entire system. One pump percolates water up through the wetland, maintaining water clarity. Two additional pumps supplement the flow volume for the waterfalls and stream. Within the lower pond, biological filtration was not necessary; only mechanical filtration for the pumps was needed.

Water circulation was improved for the lower pond by incorporating a fourth smaller pump at the pond, with a discharge line to subsurface jet outlets concealed below the gravel and cobblestone bottom of the pond. The issue was not aeration. The wetland, stream and falls are sufficient for that. Rather, it was a circulation problem along the basin's eastern edge. The constructed wetland was purposefully over-sized for the capacity of the pond to further enhance filtration.

The large courtyard/outdoor terrace is adjacent to the east end of the building, which is a dining room. The terrace and dining room accommodate after-hours events for the staff, plus corporate events. The water feature is a rainwater catchment. Overflow from the lower pond is directed to a 6,500-gallon underground vault to make up for the weekly water lost to evaporation in the dry San Antonio climate. During periods when the cooling load of the HVAC system has minimal condensate output and there has been no rainfall, potable water supplements the pool. The water feature is bordered by turf mix of native "Blue Gamma' and Buffalograss.

NuStar is actively managing the water feature to sustain a variety of wildlife. Plantings in the water feature achieve approximately 75 percent coverage of the surface area of the pond for shade benefits and habitat enhancement, supporting fish and local amphibians, birds, reptiles, small mammals and other local indigenous wildlife.

The larger overall campus landscape design primarily features native plants, which need little additional water once established.

While flash flooding recently made headlines, Texas is facing a historic three-year drought. The city must enforce water-management strategies developed by the San Antonio Water System (SAWS), the city's water purveyor. SAWS, however, granted NuStar Energy a permanent variance to allow for the management of the water feature as a wildlife habitat through all stages of drought. Recently, SAWS recognized NuStar's new corporate office with a Refreshing Ideas Award for water conservation and environmental stewardship.

The concrete and composite lumber footbridge (ChoiceDek) affords the perfect spot to lean over the hand railing to take in the falling water's action and look into the reflecting pool. Six sets of flagstone steps with metal handrails, 6-inch risers and 18-inch treads allows one to follow the falling water to the bottom pool.

Project Team
Client: NuStar Energy LP • Location: San Antonio
Architect: RVK, Inc.
Landscape Architect: RVK, Inc., Larry Hicks, ASLA, Principal
Landscape Architect: JEK, Inc.
Mechanical & Electrical Engineering: Burns DeLatte & McCoy, Inc.
Water Feature Biofiltration Design Consultation: Aquascape, Inc.
General Contractor: SpawGlass Contractors, Inc.
Water Feature and Courtyard Hardscape: ValleyCrest (Austin)
Landscape & Irrigation (including water plantings): Milberger
Electrical Contractor: Alterman Electric
Mechanical Contractor: Dynamic Systems, Inc.
Plumbing Contractor: Pesado Construction Co.

Vendors
Water Feature Equipment: Aquascape, Inc.
Fire Pit: Fire Gear USA
Low Voltage LEDs: Vista Professional Outdoor Lighting
Composite Lumber: ChoiceDek
Site Lighting Post Lamps and Bollard Fixtures: Two Hills Studio
Water Storage Tank: EcoRain Systems Inc.
Wet Well/Basin: Advanced Drainage Systems/Nyloplast
Stone: Materials Marketing/AJ Brauer Stone Quarry