Loch Norse Commons at Northern Kentucky University

Challenge

One of the most significant challenges was to eliminate groundwater seepage into surrounding building structures while maintaining enough stormwater storage volume in the impoundment lake. While the schematic/conceptual plan was developed with a known budget, this budget was crafted several years prior to the implementation of the project. 

Solution

A 2-tiered lake system was devised to help lower the water table near the northern end of the lake. Lowering a portion of the lake by just 1.5 ft eliminated the water intrusion into surrounding buildings like the library because it lowered the water table near this part of the lake. The lake system retains critical storage capacity for storm events. To keep the project within budget, iterations of material selections and alternative construction methods were constantly assessed throughout the implementation phase. Input from contractors was also solicited to evaluate options.

• The 2-tiered, 1525-sf lake system is supplied by a drainage network that collects stormwater runoff from approximately 31 acres of campus. The stormwater is detained in the lake before emptying into a small unnamed creek off of Louis B. Nunn Drive.
• The lake system acts as a water table buffer for surrounding buildings, lowering the water table near the library and lower lake area.
• Two small waterfalls – an infinity waterfall from the upper pool and a central spillway between the two ties of the lake – provide appealing sights and sounds of water.
• Coconut coir logs and native vegetation line the soft northern edge of the lake, helping to stabilize embankment soils against southern winds and erosion.
• The northern edge of the lake was planted with 17 species of native vegetation, including: perennials (pink turtlehead, mistflower, rose mallow, yellow flag iris, blue flag iris, cardinal flower, great blue lobelia), grasses (Frank’s sedge, river oats, prairie switchgrass, indiangrass), groundcovers (marsh marigold, green and gold), and shrubs (indigo bush, buttonbush, silky dogwood, Virginia sweetspire.
• The lake is inhabited by a variety of reproducing aquatic species and waterfowl including: goldfish, smallmouth bass, catfish, red-eared slider turtle, mallard ducks, and blue heron.
• A new 150-ft bridge crosses the center of the lake, providing a more efficient connection between the central and eastern sections of the campus. The bridge surface is a boardwalk made from 1,820 sf of composite decking.
• On the southwest side of the upper lake, the concrete walkways include permeable paving insets to help slow the flow of stormwater runoff to the lake.
• LED lighting and emergency “Blue Phones” are located along walkways for security and wayfinding.
• 17 steel and wood benches are located around the lake and on the bridge.
• 6 new nodes where walking paths meet create “collision” spaces that foster interaction among students, faculty, and staff. 

• 1,820 sf of composite decking were used on the bridge. Composite decking materials cost about $7 per sf, 56% more than traditional wood decking, which costs about $4.50 per sf. For this project, the material cost of the composite decking was about $4,550 more than it would have been for traditional wood decking. However, the wood decking would cost an estimated $1,500 per year to maintain through cleaning and restaining. Therefore, the additional cost to maintain wood decking would surpass the additional cost of composite decking in just 3 years. 
• There are 30 30-watt LED lighting fixtures in the plaza area. These cost about $150 per bulb, 140% more than traditional halogen bulbs, which costs $62.95 each. However, over their 13-year life, the LED bulbs will save an estimated $65,000 in energy and replacement costs compared to halogen bulbs.

• In an attempt to control the erosion of the embankment along the lakeside, the designers decided to line the shoreline with coconut coir logs. The logs were not only successful in helping to maintain the embankment’s integrity, but have also positively impacted the vegetation by providing proper soil conditions. Native wetland plants have flourished and established strong roots through the logs and into the earth, further strengthening the embankment.
• Structural design modifications had to be made to account for conditions discovered beneath the surface. A more extensive geotechnical investigation might have revealed these issues and given designers a better understanding of actual conditions so that they could be accommodated in the initial design.
• The lake tends to attract high numbers of Canada geese – and their waste. Maintenance staff have tried numerous ways to discourage their presence, such as displaying plastic predators, playing loud music, and, most successfully, using a geese-chasing dog. This keeps their numbers down, and their waste out of the lake, but is a continuing maintenance necessity. 

Decking: Trex composite decking

Project Team

Landscape Architecture, Civil Engineering, Planning: CARMAN
Campus Master Planning: The Campus Studio
Structural Engineering: Senlar, Campbell & Associates
Electrical and Lighting Engineering: Kaiser Taulbee Associates
Geotechnical Engineering: Thelen Associates, Inc.
Construction General Contractor: Morel Construction Company
Construction Subcontractor: Carlisle Excavating Company
Construction Subcontractor: Rose Seeding and Sodding
Construction Subcontractor: Rogers Concrete
Construction Subcontractor: Luce Electric
Construction Subcontractor: Ranger Contracting
Construction Subcontractor: Tri-Star Contracting

Role of the Landscape Architect

The landscape architect was the prime consultant and primary contact for Northern Kentucky University throughout the design and implementation of the project. The firm facilitated and managed design aspects of the project, utilizing campus planners, structural engineers, and electrical engineers as consultants. The landscape architect prepared all construction documents with assistance from structural and electrical engineers.