The power of the natural elements can't be underestimated, advises Keith Bailey, principal with HDR Architecture in Alexandria, Va., who has led multiple seaboard design projects over the past 25 years. The effects of wind, salt air, soil, and seawater become major design considerations, typically requiring an extra layer of protection. Hardening all building systems for emergencies and assuring two-way access under storm conditions are engineering imperatives. Coastal research facilities are typically sited on the water in remote areas, in the kind of location that calls for more attention to security. At the same time, the projects are rich in psychic rewards: owners and planners invariably team to take advantage of the beauty of the natural setting through features like interior waterfront views and inviting outdoor areas for interaction or inspiration.

"These labs are here for two reasons," Bailey says. "One is access to sea water, and the other is access to the sea itself." He offers a treasure trove of advice on how to coexist and adapt to the elements instead of fighting them.

Seawater 101

The first thing to recognize about seawater in these environments is that it's a life support system, so like lights and other critical building systems, it has to be on emergency power. Seawater quality is another high-priority item given the degree to which aquaculture is a frequent research focus. Bailey notes that there are multiple sources—the ocean or the intracoastal, wells, trapping, even on-site manufacturing.

"Many facilities have multiple seawater taps," says Bailey. "The most I've seen at one place is five different taps, but there are at least ten different alternatives."

To transport seawater from its source, outdoor piping is typically mounted along a dock, often with an intake anywhere from 1,500 feet to half a mile out into the bay to avoid turbidity from overhead boats. Despite the distance, the intake has to remain accessible in some way so its screens can be cleaned regularly.

A seawall pump draws the seawater from the bay into the facility. If the water is to be unfiltered and delivered immediately, a booster pump at the building is needed to distribute it through the pipes that take it directly to a benchtop tap. Sometimes, Bailey points out, unfiltered systems first transfer the seawater to a storage facility, which can be at another location. Again, a booster pump is required to bring the water to the building and make it available at the bench. Filtered seawater undergoes the pumping process twice, first at the coastline and then when it reaches the building.

Temperature-treated seawater requires either chilled water piping or heaters at individual tanks, and then an ultraviolet treatment, according to Bailey. Some systems might employ ozonation as well as the addition of oxygen.

"This becomes the most expensive system," he comments, also noting that it is a prevalent one, despite its cost.

Seawater is typically distributed through an overhead network of pipes, with built-in redundancies to allow for the wear and tear inflicted by the highly corrosive salt content, as well as by the miniscule creatures remaining in the water that serve as a good food source for fish.

Budgets for filtering systems can range from $250,000 to $500,000 per facility, Bailey notes.

"What makes the difference is whether or not you use stainless steel equipment for aquaculture engineering versus PVC plastic known for swimming pool technology," he points out. "It's better to buy an inexpensive plastic pump off the shelf and throw it away every few years than to employ the very expensive stainless steel equipment. Stainless steel is affected by seawater, and even the highest qualities will still corrode," he stresses.

Water Recycling and Disposal

Some saltwater systems acquire recycling capabilities by rotating the water through a network of storage tanks, backed up with redundancies for life support as well as maintenance. One tank is typically emptied weekly into a retention pond sized to accept the discharge. The tanks have an overhead hatch affording interior access for cleaning.

Occasionally, scientists use the tanks as fish habitat, for example, in studies exploring the relationship between fish dwelling depth and outside temperature.

"The fish tend to go deeper as the temperature gets colder, and then they rise when it is warmer," Bailey relates. Portholes at different heights of the tank enable passersby—as well as researchers—to view the creatures in their quasi-natural environment.

Both the intake and discharge of seawater require regulatory approvals at several layers of governmental authority and typically entail measures to mitigate sea grass and mangrove disturbance.

"Permitting is very heavy," Bailey relates. "We literally started the permitting of one facility even before design, and we had to wait on the permit after the building was finished. In those days it was seven different permits. Now they have reduced it to about three.

"It is still a difficult thing to do," he continues, noting that provisions must be made for wastewater from equipment and personnel wash-down areas.

Individual structures have multiple discharge drains in the floor, especially in lab zones, where in addition to normal drains, chemical drains and separate seawater drains for recycled seawater are present. With so much water around the benchtop, Bailey cautions that the bus ducts, raceways, and drop-down electrical receptacle coils that distribute electricity to the benchtop must be strategically located in dry areas.

"Many of these areas will actually include a trench right in the middle of the casework for the seawater to be poured into," he observes.

Finish Floor Elevations

Research conducted by the National Oceanic and Atmospheric Administration and the federal Environmental Protection Agency indicates that over the next 10 to 15 years the structural design of coastline facilities will have to raise finish floor elevations by a meter and half.

"Four and a half or five feet is a significant amount," acknowledges Bailey, explaining that documented rising water levels and sinking land levels are responsible. As a result of coastal studies, the EPA has determined that only buildings above the 100-year flood plain will be allowed. MEP equipment can sit open in a room—a prospect especially appealing to maintenance personnel—as long as it is outside the 100 year floodline.

"Generators, transformers, and things of that nature have to be both accessible and outside of the flood zone, but tank farms can certainly be flooded without any problem, although sea-life may be lost," he says.

One project Bailey was recently involved in featured a service yard with all the equipment up on stilts to attain the 100-year height. Shut-off valves also need to be located above the water line.

Ambient Moisture Protection

Moisture is an omnipresent challenge, within and outside of the building. It's essential to identify and shore up vulnerable areas around the perimeter, equipping them with moisture barriers for enhanced protection, Bailey advises.

All indoor and outdoor materials should be corrosion-proof. In one instance, after just six months' exposure to seawater spray, a metal gas shut-off panel was so damaged that it failed final inspection, Bailey reports. It was removed and replaced with a plastic panel. Similarly, hollow metal framing deployed inside the labs can also corrode within six months. On the other hand, Bailey cites a university research facility along the Carolina coast that was built in 1935 entirely of wood.

"It is still in better condition as a laboratory than new facilities built in the 1960s out of contemporary materials," he notes, strongly endorsing the low-tech approach of using redwood or pressure-treated lumber in the facility construction and fit-out.

Bailey specifies lab casework with a six-inch-high pressure-treated base because of all the water that spills onto the floor.

"There is no way to move five-gallon containers full of seawater and pour the contents into something else without making a splash," he insists.

Floors and surfaces have to withstand washdown and spill clean-up. Wet labs and aquaria need hose bibs. Sinks and other fixtures should be made of plastic materials to keep corrosion in check.

When it comes to the building skin, exterior surfaces should be of the most enduring materials available. Concrete framing systems are the best, states Bailey, issuing the reminder that if steel framing is used to reduce cost, it must get a protective wrap.

"You don't want to leave those systems exposed or they will immediately start showing corrosion due to the airborne seawater inside and outside the building," he advises.

Roofing choices must also take high winds and hurricanes into account. Bailey and his team have discovered that standing seam metal roofs will likely remain in place in the kind of severe storms that have stuck coastal areas over the past few years. He points out that airborne debris in a storm can be a major problem. Although very expensive, extra-strong window glass has been engineered to withstand the force of flying objects. It's a worthwhile investment in light of the huge potential for loss, Bailey remarks.

"As soon as you lose a window in these facilities, the pressure can suck everything inside the building outside," he states.

By Nicole Zaro Stahl

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