People are being drawn in increasing numbers to our coastlines for access to sandy beaches, fish catches, and the alluring beauty of the sea. Similarly, marine scientists are drawn to the coastline for ready access to the sea and its extraordinary array of marine life and seawater—a necessary ingredient to the life-support systems of sea life.
Designing science laboratories that support healthy marine animals requires environmental alignment with dynamic seawater coastlines, presenting numerous issues for architects and engineers. Incorporating sustainable design that overcomes seawater corrosion and natural disasters is one the greatest challenges facing buildings that interface with the sea. Design teams must prepare for myriad scenarios, such as: the forces of salt water corrosion, seawater exposure from the exterior, or salt water spray attacking a science teaching and/or research laboratory facility used for marine biology and oceanography; seawater spills; active recirculating supply seawater piping; aquaria tank evaporation; and a facility’s direct exposure to seawater within. Large fresh air intake grilles, located low on a building exterior, are required for 100% outside air at HVAC rooms that must be located away from saltwater spray, fume hood chemical discharge, and vehicle exhaust. All building material finishes in the coastal environment need detailed study to insure that they will not break down from corrosion due to seawater exposure nor be damaged by hurricane forces.
Coastal flooding during storm events requires the use of ramps at Eckerd College Marine Laboratory rather than elevators.
Seawater tables are provided in teaching labs at Eckerd
College with accessible seawater piping system exposed
Coastal Climatic Factors Highly Influence Building Design. Climatic factors are of extreme importance for coastal sites. These include a 100-year flood plane, prevailing breezes, 140 MPH wind speed resistance, wind direction, barometric pressure, temperature, solar orientation of the building for maximum energy-conscious performance, solar screening at glazing, and retention ponds for holding rainwater and spent seawater. Each reoccurring factor affects the location of the building footprint. Sites in Florida, for instance, have coastlines that face east, south, and west, with all orientations requiring solar screening from the reflected glare off the water.
Teaching and Research Marine Lab Design. Floor plans of wet laboratories, whether for teaching or research, are most often placed on a consistent planning module, often 10’8” to 11’ wide by 32’ to 35’ long, based on the requirements of individual researchers. Overhead piped services often include vacuum, compressed air, gas, hot and cold water, chilled water, filtered seawater, R.O. water with floor-mounted general floor drains, seawater drains with cleanouts, and chemical waste drains. All valves need to be easily accessible to regulate the flow of piped services. Main valves and breaker boxes must be placed in alcoves at lab ingress and egress to be able to turn off all services should an emergency arise. Emergency showers and eyewash stations should also be provided but may be in hallway alcoves and shared by multiple labs. Electrical needs include 110v ground fault receptacles and 220v power, telephone, data, task lighting, overhead corrosion-resistant lighting fixtures, and drop-down power reels to service equipment needs. Refrigerators and any electrical device providing life support to sea creatures need to be on emergency power. VAV 5’ to 6’ wide fume hoods, often with manifold exhaust, should also be provided.
Daylighting is another important element for lab occupants and the reproduction cycles of sea animals. Windows for viewing, with light controlling devices, must be inoperable due to the restrictions of controlling 100% outside air requirements at fume hoods. Some marine labs introduce skylights over sea animal tanks to maintain natural 24-hour night and day cycles. Light fixtures are often mounted over the holding tanks to control breeding experiments. Horizontal support rods may be mounted in a grid at the ceiling, allowing for flexibility in lighting or for positioning cameras above the tanks for monitoring at remote monitors.
Horizontal electrical strips need to be plastic, and wet walls in wet labs, should be finished with ceramic tile wainscots, epoxy-painted marine plywood, redwood panels, or epoxy-painted water-resistant gypsum board. Marine plywood and redwood panels have the advantage of easily securing the secondary seawater and chilled-water piping to the wall to deliver water to individual sea-life holding tanks. Whatever the finish or trim on a wet wall, it must resist the air-borne salts or direct splash of highly corrosive seawater. Even many grades of stainless steel will show corrosion over time.
Teaching labs often use three tiers of seawater aquaria, stacked from narrow with shallow trays at the top, to wide with deep tubs at the bottom. This configuration is referred to as a sea-table and is often built into an “A-frame” structure. The smaller trays hold small sea creatures and the seawater overflows into the next tray. The middle tray houses larger sea creatures, and its seawater overflows into the large tub at the bottom, where the largest sea creatures live. The bottom tubs are connected to the seawater drains. Another version of a sea-table may be a linear shallow tray table top with individual small glass aquaria set on the table, where each aquarium receives a small stream of re-circulating seawater, and a central drain captures the seawater runoff. Epoxy-coated, pressure-treated lumber with stainless-steel fasteners are sometimes used to support a sea table. The use of low-tech materials seems to be the best solution, given the corrosive and potentially damaging effects of seawater. Hose bibs can be provided at wet walls to clean tanks and wash down the salt spills on the concrete or clay tile floors.
All other walls in a wet lab receive epoxy paint. Floors are most often sealed concrete, clay tile, or seamless sheet flooring, turned up at the wall to form a base. Ceilings tend to be water-resistant acoustical tile with plastic suspension supports. Open ceilings are discouraged, due the eventual corrosion of exposed piping and metal hangers. Stainless-steel pipe hangers and anchors should be specified. Wall and base cabinets are wood with pressure-treated, water-resistant wood used at 6” high floor bases. Casework tops may be as low-tech as acid-resistant plastic laminate, or they may need acid-resistant resin or stone tops. Special attention should be given to the design of seams to assure that no moisture penetrates to the substrate materials. Perimeter walls often require wood cabinets for storage and floor-mounted equipment alcoves. Depending on the level of research, two researchers may be able to share a fume hood in an adjacent alcove. Finally, any equipment that can be stored in a lab support space, in a room without open seawater tanks, will last longer due to seawater’s corrosive forces.
Sources of Fresh Seawater.
• Option 1: A 6” diameter well may be drilled in close proximity to the marine lab with a pump delivering seawater to the building. An additional booster pump may be provided to pump seawater to the tank farm or to the multi-level wet lab areas located within the facility. Sand filters and appropriate valves should be placed at both locations. Plastic pumps, valves, filters, and piping, similar to swimming pool technology, are more economical and easier to maintain and replace than expensive stainless steel pumps, which along with their high first costs, are eventually subject to seawater corrosion. All of this equipment should be located in a secure area, so the life-support systems cannot be modified by anyone other than by trained marine lab personnel (CMU low walls with a roof hatch for a cover prove to be a good, secure pump house structure).
• Option 2: Depending on the quality of the water, PVC piping can be placed on a bay, gulf, or ocean bottom, and then extended several hundred or even several thousand feet away from the seawall or coastline. The depth of the pipe – usually 8’ to 15’ – is such that water disturbance is low when boats pass over the piping. Water samples need to be tested to determine other factors, such as degree of salinity before the final distance, and the seawater’s depth and route. Mangrove, sea grass, and water bottom disturbance will also need regulatory reviews and approval with some mitigation probable.
• Option 3: Artificial or manufactured seawater can be utilized; however, food sources will not be present, as they exist only in native seawater.
• Option 4: A seawater pump can be mounted on a barge with flexible hoses and piped to a pump station located at the coastline. Since storage tanks will exist at the building, refilling of these tanks will probably occur on a weekly basis.
• Option 5: Milk trucks, converted to hold seawater, can make weekly seawater deliveries.
The quality of the estuarine, bay, gulf, or ocean seawater is essential to the support of sea life and experiments. Unfortunately, permitting the hundreds or thousands of feet of supply lines along the bottom of a bay can be costly in material and labor, and building schedules are often complicated, due to the necessity for multiple permits by numerous agencies. It is not uncommon to see the permitting process for seawater supply and return take as long as the actual construction of the marine lab.
Returning spent seawater to the bay, in lieu of using seawater retention ponds, is a longer, more difficult process due to regulatory requirements for filtration and treatment. Maintenance of both supply and return unfiltered seawater systems can be frequent and time consuming, with many clean-outs required. Fouling is often due to growth on the internal lining of unfiltered supply lines. Therefore, redundant supply lines are required, where one is under maintenance when the other is actively delivering seawater. Pump and filter systems are also necessary at the water’s edge and at the building where it is delivered to various distribution points.
Designing an Active Seawater System. Marine science buildings that are located on a bay, gulf, or ocean coastline are often equipped with active recirculating seawater systems flowing through its wet laboratory areas.These life-giving systems for academic teaching and research marine labs may require only one type of seawater, drawn from an adjacent source. They cost approximately $250,000 to $1 million to construct and demand an aquaculture specialist’s design expertise. At large established marine research labs, three to five different seawater taps may be provided at each lab to meet differing marine animal seawater needs.
The primary challenge of creating enduring buildings is the introduction of a filtered or unfiltered corrosive-resistant, re-circulating seawater supply pressurized piping system that is mounted, in an accessible area, approximately 7’6” overhead. This allows for ease of regular, periodic maintenance, piped into teaching and research laboratories, lab support spaces, and aquaria rooms. If any dead legs exist in the seawater piping, they will foul piping, resulting in water that is contaminated and pipes that need cleaning.
Re-circulating Fresh Seawater System Loop. To transport seawater from the booster pump to the wet walls and aquaria areas of wet labs, high-pressure PVC piping at all elbows, connectors, and cleanouts at 10’ to 12’ spacing, need to be a minimum 150 PSI, although, actual delivery PSI may be significantly less. Normally, 4” diameter PVC piping is used at low pressure to 1) minimize damage to food sources within the seawater, and 2) reduce buildup of debris on piping walls. Redundant supply lines are provided, especially with unfiltered seawater, to allow maintenance on one line while the other is providing active delivery of life-supporting seawater.
Supply line seawater temperature can vary significantly from the inside building temperature, so supply piping must have an insulating wrap to avoid condensation drips. The path of the seawater loop needs to be reviewed to avoid any dead legs in the system where debris and un-circulated seawater may be trapped and contaminate the seawater tap serving a tank. Flexible clear plastic tubing can be extended from plastic supply valve cocks mounted on the sides of the supply lines, often mounted at 2’ on center over wet walls, seawater sinks in teaching and research labs, tank farms, and aquaria rooms.
Dedicated seawater trench or area drains with surface funnels to capture tank drains, may be placed adjacent to wet walls to collect spent seawater. If the wet lab has a BSL-3 or ABSL-3 rating, redundant drain systems should be provided, as well as UV and chlorination treatments to the spent seawater prior to disposal or re-circulation. Spent seawater disposal can be sent to a dedicated retention pond or returned to the bay, gulf, or ocean with proper permits, filtering, and chemical treatment. Cleanouts should be provided in the 4” diameter waste return line, at a minimum of 20’ apart for periodic maintenance.
Maintaining the Water Quality of the Seawater System. Saltwater testing at the fresh seawater source as well as at the point of delivery to holding tanks at the building, will determine if the seawater quality is acceptable to researchers (it is the responsibility of the researchers to define the source criteria so that delivered seawater meets the needs of marine life). The quality of the fresh seawater is maintained by controlling:
• Water intake location. If the source is drawing seawater from the bay, gulf, or ocean, the pipe intake should have a stainless steel mesh filter that can be lifted to the surface and be cleaned periodically. The mesh is usually 1/4” to 1/2” in opening size to prevent large sea life from entering, still allowing small food sources to enter the system. The size will vary and will generally be more open for unfiltered seawater than for filtered seawater. The depth of the intake is 8’ to 15’, based on the extent of disturbance at the surface.
• Distance of travel in the supply piping. Piping distance should not be more than approximately 3,000 feet, due to the lack of oxygen being added to the water.
• Temperature at the holding tanks. Chilled water piping at the building, available at aquaria and lab wet walls, along with thermometers and heaters provided at each holding tank, are ways to ensure that seawater temperature matches the source temperature.
• Oxygen content. Ozone generators, tank air pumps, and skimmers may be provided at the building and individual tanks to control oxygen content.
• Sea creature food sources. Important nutrients necessary for marine animal health are contained within the seawater. Water pressure that is excessively high or screen filtering that is overly fine can remove too many of the miniscule creatures and thereby reduce the seawater’s overall quality.
• Turbidity at the point of intake. The stirred up waters from boat and ship movements above a seawater intake need to be avoided. Increasing the depth of the intake to find undisturbed waters, is the solution when the intake is in the path of navigable waters. Often, this requirement will extend piping far into a bay, especially in areas such as Florida, where shallow seawater depths along the coastline are 4’ to 6’ and can extend thousands of feet into the bay.
• Water pressure. Low pressure delivery of seawater allows small living nutrients within to survive while the seawater travels to the holding tanks where sea creatures live.
• Filtration. Most seawater systems filter water prior to being introduced within the building. This reduces the fouling of the lines and removes some of the parasitic animals found in the water.
• Quantity. The sizing of seawater holding tanks and the delivery piping system should be adequate to meet the facility’s needs. Re-circulated water will need to be purged from the system on a weekly basis.
• Salinity. Researchers must test the seawater to confirm a level of salinity necessary for the sea life that they support.
• Age of the seawater. A week’s supply of seawater stored in holding tanks should be adequate and allow for weekly purging of the system to keep fresh seawater available within the system.
• Constant power source. Pumps need uninterrupted power, which means that the pumps of a seawater system must be on emergency power in the likely event of coastal storms that interrupt the power supply.
There are numerous factors to consider when designing specialized marine laboratories. These range from the need to curb seawater corrosion to understanding how to prevent incredible losses from high-wave seawater surges, heavy rain flooding, and high-wind damage from hurricanes hitting coastal sites. Design professionals must be extremely attentive to the special needs of buildings that house researchers and their marine friends when living on our dynamic coastlines.
S. Keith Bailey, AIA, LEED™ AP, is an architect, with a science and technology focus, at Einhorn Yaffee Prescott, Architecture and Engineering, P.C., in Washington, D.C. He has been involved with the design of more than a dozen biological and marine wet labs most often built on coastal sites. Laboratories for marine life for government agencies have included the Smithsonian Institution, U.S. Geological Survey, Florida Marine Research Institute and higher education facilities such as, Florida International University, University of South Florida, University of North Carolina, and Eckerd College. Keith can be reached at firstname.lastname@example.org or 202-471-5106.
Keith Bailey will be speaking on laboratory design for marine animals at the 2007 TurnKey Conference.