Evaluation of marina disaster potential for use in planning and design J. Guerry Taylor Gwcrry 7by/or, f.&, /^c., f.o. Box 70% Mr.

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1 Evaluation of marina disaster potential for use in planning and design J. Guerry Taylor Gwcrry 7by/or, f.&, /^c., f.o. Box 70% Mr. Caro/ma, Abstract Unanticipated and unmanaged natural and man-made disasters can cause substantial damage to marinas and adjacent facilities. Hurricanes, floods, and fires are potential disasters for many marinas, and their likelihood of occurrence and the resulting risk of damage should be incorporated into the design analysis of each marina facility. Insurance companies are becoming more critical of design and operations of marina facilities that do not address potential disasters. The lack of disaster planning during design often transmits into increased insurance premiums or perhaps subsequent litigation for damages. This paper analyzes the approach to evaluating disasters and relating the potential disaster occurrence to planning, design, and operation of the marina. The author, a practicing Professional Engineer in Charleston, South Carolina, USA, has experience in evaluating damage from natural disasters in marina facilities that resulted from Hurricane Hugo and Hurricane Andrew and from recent ice storms in the United States. The purpose of the paper is to bring to the planning and design professional an awareness for the potential for disaster and to assist in developing a methodology for relating a potential disaster to its effect on marina design, insurance, and operational procedures. Fire, The Man Made Disaster General Fires in marinas give little warning, however, the conditions that promote fires are obvious to the trained and risk sensitive person. Thus fires can be controlled to a large degree by design, marina operations, and an awareness of what to do in the event of fire disaster. Fires in marinas do not often cause loss of life, however,

2 328 Marina they often cause extensive damage to facilities, boats, marina business, and loss of marina image. Other marina disasters like hurricanes (cyclones, storms, etc.), extreme weather events (ice, flood, etc.), and other natural events (earthquakes, tsunamis, etc.), follow an approximate pattern of probable return and can thus be - for design purposes - accounted for through statistical analysis. However, fires do not follow similar patterns, and must therefore be controlled by codes and regulations or an ongoing program of prevention based on a risk assessment of the damage that could result from a marina fire occurrence. Risk Assessment As a first step in design of fire protection for marinas, it is important to establish the protection level required for the marina. Often the minimum protection required is dictated by codes or regulations established by national or local fire agencies. However, these codes are only minimum requirements and may not satisfy the requirements for a marina that has expensive boats or is adjacent to an exclusive development with restaurants or tourist attractions. Marinas with drystack storage of boats require special treatment (firewalls, sprinklers, and space compartmentalization) as they are often treated as buildings and must meet the same requirements as buildings for fire protection. Once the desired fire protection for the marina is determined, it is important to assess the localfiredepartment's ability to provide support for a fire emergency. If fire support equipment or personnel are not available through the local fire department, then the marina facility may have to provide these features (water, pumps, even trucks with hoses) within the marina environs. The lack of support through the localfiredepartment or the cost of providing facilities from the marina budget should not be cause for reducing the required level of fire protection. However, it is possible that a re-evaluation of the marina resulting in a reduced functional scope (smaller, less expensive boats, reduced exposure to buildings, etc.) should be made so the desired level of fire protection can then be maintained utilizing local fire department assistance or a manageable allocation from the marina budget. The Design/Operations Relationship in Fire Protection It is important that the marina designer measure the fire protection design against the marina management's commitment to provide operational support (facilities, education, and training). The best way that the marina designer can reach a level of comfort in the design/operations relationship is to be an active participant - perhaps the author - in the promulgation of the Marina Fire Protection Plan. The Marina Fire Protection Plan should include the details for inspection, education, training, and afireemergency response plan. The fire emergency response section of the Marina Fire Protection Plan should include as a minimum the following: 1. Description of fire fighting facilities including location of critical elements such as pumps, valves, electric panels, alarms, shut-offs for fuel system, storage of hazardous and flammable materials, and fire fighting supplies. 2. A checklist of priority items to promote: (a) saving human life and

3 Marina 329 reducing injury, (b) reducing damage to boats, (c) controlling damage to facilities, and (d) avoiding environmental pollution. 3. Procedures for dealing with boat owners, the public, the press, and insurance investigators in the event of a fire disaster. Design Features That Promote Good Fire Protection There are measures that the design professional can take to reduce the risk of disaster damage from fires. Following are some generalized concepts that should be applied in almost every marina: 1. Provide adequate pressure in fire lines - there should be no conflict (separate lines are preferred) between fire lines and domestic water supply on the docks. 2. Non-corrosive or non-ultraviolet light sensitive pipe for fire water supply. 3. Non-corrosive hangers and attachments for fire lines and fire fighting equipment. 4. Coordinated locations for fire lines, hose racks, and hoses, if required. 5. Reduction of combustible construction and building materials in structures in the marina. 6. Adequately designed supporting structures for heavy fire fighting equipment. 7. Adequate space for fire fighting equipment access on gangways, docks, and walkways. 8. Adequate reserved access in parking areas and traffic lanes for vehicular firefightingequipment. 9. A dockside communications system to promote quick action/response time. 10. Shut-off valves on fuel systems - shut-offs should be installed at the fuel dock facility, the Harbormaster office, and at the fuel pump (tanks). 11. Shielded electrical service (conduits, sleeves, etc.) will reduce exposure to a potential fire hazard, especially around areas with combustible materials. 12. Use shore power receptacles designed for marine use and housed in approved cabinets. 13. Install approved portable fire extinguishers in sufficient quantity and in critical locations to provide a quick response for early detected fires. Fueling docks are high risk areas where supplemental fire extinguishers should be used. 14. Designate separate storage facilities for hazardous and/or flammable materials and provide fire protection (water, hoses, fire extinguishers, etc.) consistent with the assessed risk at that location.

4 330 Marina Photo 1. (Courtesy of: Fire Equipment and Training Company) Remnants of a 2.4 million dollar drystack fire in Wilmington, NC, USA The fire was started by children playing with fireworks. Photo 2. (Courtesy of: Fire Equipment and Training Company) Fire spreads quickly from the boat in the center to adjacent boats.

5 Marina 331 The Total Marina Fire Protection Picture The first element of fire protection should be provided by the designer in his assessment of fire potential and damage through the layout and specification of equipment and facilities in the marina. The second level of fire protection for the marina is provided by the education/operation/ prevention program for fire awareness established by marina management. This activity includes the detection/response activities related to daily, weekly, and monthly inspection and quick corrective action when potential fire hazards are detected. The third level is provided by the fire response plan that produces damage control in the case of fires - or damage assessment in the case of a fire catastrophe. The final element of marina fire control is provided by insurance which covers damage to boats, facilities, and loss of business. If all other previous elements are in place, the risk of damage is lessened and insurance premiums should be proportionately reduced. Reduced insurance premiums should be considered when offsetting the cost associated with fire hazard abatement programs. NATURAL DISASTERS General Hurricanes (typhoons or cyclones), ice storms, sustained high winds, and tsunamis are typical natural disaster events that are completely out of man's control for occurrence. Some natural disasters give more warning (hurricanes) than others (tsunamis), however, these events usually occur within certain geographic locations on a regular basis such that there is high expectation that the event will occur. Event Return Analysis The probability of occurrence (encounter probability - %) of a defined significant return period is the chance that the event will occur or be exceeded in a given time period (design period or project life). We define the return period of a twenty-five year event as one in twenty-five years or a twenty-five year significant event. This return period definition also serves to remind the designer that a similar event has happened in the recent past. It may not be predictable that the event will come in a certain year, but it can be anticipated that a similar event will have a high probability of returning in the specified time period; see Figure 1, Twenty - Forty Year Project Life Significant Event Description versus Encounter Probability. If we use thirty years as the standard planning/design period, we see that there is a seventy-two percent (Al) chance of a twenty-five year event returning in the next thirty years. A similar analysis shows that there is a forty-six percent (Bl) chance of a one infiftyyear event returning in the same thirty year period. It must be realized that this statistical approach is representative for any thirty year period. To relate the analysis to the site, an historical analysis may show that there had been no incidence of a twenty-five year orfiftyyear event in the past ten years. An argument can be made that the planning/design period analysis should be extended by ten years to make a forty year analysis (ten years past plus thirty years future).

6 332 Marina If we look at the forty year curve, we see that the chance of a fifty year event has increased from forty-six percent (Bl) to fifty-eight percent (Dl) - a net increase of twelve percent. A similar analysis of a twenty-five year event shows an increase of nine percent (Al to Dl). Figure Year Project Life, Significant Event Description vs. Encounter Probability Significant Event Description (yr) Relating Extreme Events to Risk of Damage/Disaster Although we may know the probability of significant events' return in a given design period, there is still not a direct relationship to risk of failure. It is logical to assume that a one hundred year event will do more damage than a twenty-five year event, but relating the event to risk of failure takes further consideration. The significant event damage potential is usually related through historical performance or other means to design values for wind speed, wave height, current, flood elevation, depth of snow, thickness of ice, etc. These environmental factors increase in severity as the significant event return period increases. For this reason, there is a very strong interrelationship of event return, risk of damage, and cost to reduce that risk to acceptable design conditions. Reducing Risk of Damage Through Marina Planning and Design With a good appreciation of the significant design event and its environmental features, the designer can apply his planning skills to make the site and the use

7 Marina 333 more amenable to a visit by a significant natural disaster event. Following are some of the generalized approaches to amelioration of a disaster event: 1. Reorientation of critical features (entrances, fueling facilities, buildings, etc.) to reduce exposure. 2. Optimize critical lifelines and support facilities (electrical, water, communications, sanitary lines, etc.) so that they have minimum exposure during the disaster. 3. Provide protected water ingress and egress to the marina, if possible. 4. Reserve land access - protected if possible - for easy evacuation or return after a significant event disaster. 5. Minimize buildings over water in the marina. They require substantial construction to remain in service during the disaster, and they often are so damaged that they have to be destroyed and rebuilt afterwards. In addition, they give a false sense of security to marina operators who often use them for critical activities or storage of needed items during a significant event. Structures over water can be a source of additional failure to other elements as they are tossed and torn during a significant event. Photo 3. (Courtesy of: Jon Guerry Taylor, P.E., Inc.) The Atlantic Intracoastal Waterway was closed to traffic when this bridge in Charleston, SC, USA was damaged from Hurricane Hugo.

8 334 Marina Photo 4. (Courtesy of: Jon Guerry Taylor, P.E., Inc.) An ice storm caused collapse of the covered floating slips in Paducha, KY, USA Preparation, Operation, and Evacuation as Complimentary Elements of Marina Design Only so much protection can be offered by design. Either the marina construction will become too costly, or the disaster design will be overdone to the point it interferes with the reasonable function of the marina. However, there are many operational activities that can be instituted to minimize or prevent loss of life and reduce damage to facilities. In many cases, natural disasters such as hurricanes, ice storms, tsunamis, storms, and floods do not occur instantaneously and thus provide some advance notice before arrival. While it may be that we do not know exactly when the event will occur, there is a predictable advance knowledge (usually from eight to twenty-four hours) before it arrives. This advance notice gives the marina operator a chance to tie boats down, secure equipment, evacuate, and plan for the return after the disaster has passed. In order to effectively utilize this time, disaster pre-planning must be done. Disaster pre-planning always pays big benefits in reduced loss of lives, facility damage, coordinated evacuation and return, early repairs, and subsequent return to business. Insurance as a Final Hedge Against Financial Disaster Some marina disasters are beyond the practical design and operation limits. When a catastrophic disaster occurs, almost everyone is equally affected, but experience has shown that those marinas that have insurance are repaired more quickly, get back into business faster, and usually upgrade their facilities during reconstruction. Each year that passes by without a disaster increases the probability of a severe disaster that will cause extensive damage. An argument can be made for increasing insurance coverage to match the increased probability and the increased replacement value of the marina facility.

9 Marina 335 Photo 5. (Courtesy of: Jon Guerry Taylor, P.E., Inc.) Boats and floating docks were thrown up on high land and into adjacent buildings during the 18 foot (6m) tidal surge from Hurricane Hugo. Photo 6. (Courtesy of Jon Guerry Taylor, P.E., Inc.) Buildings and structures over water damage easily from high winds and uplift forces from tidal surge. CONCLUSION Both manmade and natural marina disasters pose challenges to designers. A realistic determination of the chance of return combined with the assessment of the risk of damage by the disaster event can provide the marina designer with the information necessary to optimize the design with minimum cost and disruption to boating function and revenue. This protection, added to the operational protection provided by the marina management, plus insurance provides the most effective protection against damage that is reasonably possible.