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HomeMy WebLinkAboutBradley Lake Hydroelectric Project 01-17-2003Martin River Airstrip Access Road, Maintenance versus Removal AERIAL PHOTOS OF MARTIN RIVER AIRSTRIP AND ACCESS ROAD Kachemak Bay ¢ Aone Intersection with Bradley Lake Dam Access Road Battle Creek Bridge Low Water Crossing at end of Airstrip Low Roadway Section Battle Creek Slough Bridge Low Water Crossing Martin River Emergency Airstrip Kachemak Bay Old Gravel Borrow Area, Now Unattended Fish Ponds Martin River Dike Rev 01/17/03 Page 6 of 6 AEA Martin River Airstrip Access Road, Maintenance versus Removal Cost Considerations A definitive cost comparison of a one-time effort to remove the road and airstrip versus long term, annual maintenance costs (plus some cost for rehabilitation of the site following failure of the dike) is of value in determining the best course of action. Costs stated in the following paragraphs have not been definitively estimated but are based on order-of-magnitude cost parameters. The estimated cost to remove all the Martin River Access Road roadway embankment and bridges is around $200,000 to $300,000 depending on the level of restoration required along the road and at the bridges. Removal of the Airstrip would not be necessary as the runway is literally a graded gravel surface at the general elevation of the surrounding flood plain. Rendering the runway “unusable” and formally closing it with appropriate “Closed Runway” signage would cost in the range of $10,000 to $30,000. Remedial work required to restore the Martin River road, low water crossings and bridges to fully serviceable condition using construction materials available at the project storage yard would cost in the range of $100,000 to $200,000 and an additional $80,000 to $100,000 to replace decks and abutment timber walls at the two bridges. Experience the past decade would indicate awards from injury and death settlements related to aircraft crashes range form $250,000 to well over $1,000,000. This potential liability should be considered when determining whether the Martin River Airstrip Access Road and Airstrip are taken out of service. The estimated costs above can be refined when a program scope is better defined. Costs of mobilization and demobilization and equipment utilization by a contractor can be spread over a number of the tasks noted above, resulting in a lesser cost for a particular task. Rev 01/17/03 Page 5 of 6 AEA Martin River Airstrip Access Road, Maintenance versus Removal e One time cost for removal and restoration will be large. Pros- e Following removal no additional burden on project staff to monitor and maintain features. e Environmental, safety and security liabilities eliminated. Discussion of Alternatives Restoring the Martin River Airstrip Access Road and Airstrip to fully serviceable condition compliant with the FERC license for the Bradley Lake HEP requires remedial work on bridges, low water crossings and the roadbed. The developing subsidence and sinkholes in the roadbed of the Battle Creek Bridge approaches needs to be corrected and the approaches regarded. In addition, the Battle Creek Bridge waterway approach channel requires reconstruction of the guide dike on the left bank upstream side. The remnant dike has lost nearly all of its material and the creek is eroding the road embankment along the bridge approach. The low water crossing in the Battle Creek flood plain and the low water crossing at the east end of the airstrip need regarding and reconstruction to allow vehicle and maintenance equipment access to the airstrip and to restore the eroded roadbed. Battle Creek Slough Bridge is apparently in serviceable condition but the approaches need sub-grade repairs and re-grading. The Martin River Airstrip Access Road requires re-grading and some reconstruction in the area where it traverses the tidal flat between Battle Creek and Battle Creek Slough. This area has been damage by ice and the creek high flows resulting from the November 2002 storms. The Martin River Airstrip needs re-grading and brush and trees that encroach into the aircraft operations safety area and safety surface along, and at each end of, the runway need to be trimmed or removed to below the safety surface. Signage indicating the airstrip is a restricted-use private airstrip needs to be installed at the airstrip. A security plan for the Martin River Airstrip and Access Road needs to be formalized consistent with the recently mandated National Dam Safety Act. Rev 01/17/03 Page 4 of 6 AEA Martin River Airstrip Access Road, Maintenance versus Removal Given the above concerns it is recommended that AEA evaluate the current status of this project feature and make a decision as to whether it is in the Bradley Lake HEP’s best interest to: 1.) Increase the maintenance and monitoring effort expended on this feature to ensure it does not represent an environmental, safety or security liability for the project, or, 2.) Abandon the feature and remove the roadway, bridges and airstrip. This would require obtaining a license amendment prior to removing the road and airstrip. Evaluation Factors The listing presented below indicates the readily apparent pros and cons of retaining or removing the Martin River access road and airstrip from the Bradley Lake HEP based on subjective and qualitative factors presently known. Retain the Martin River Road and Airstrip - Cons- e Un-maintained or poorly maintained road/airstrip are potential environmental and safety liabilities. Cost of a single litigated loss in a small aircraft crash on the airstrip could run to over one million dollars. e Un-monitored airstrip is a potential security risk. A determined vandal could take the project out of service for several days to weeks. e Annual maintenance costs to maintain facility in environmentally compliant and safe condition could be substantial. e Eventual loss of these features is highly probable in the near future, with associated costs (unknown) to clean up area following flooding of the Martin River. Pros- e Airstrip remains available if case of an actual need for a secondary landing site ever occurs. e Noneed to file a second license amendment. Removal of the Martin River Road and Airstrip - Cons- e Will require non-capacity amendment of project with associated (minimum) risk of opening up project to regulatory scrutiny. Rev 01/17/03 Page 3 of 6 AEA Martin River Airstrip Access Road, Maintenance versus Removal river to reclaim the flood plain in the delta that was isolated by constructing the temporary dikes during construction of the Bradley Lake HEP. Restoration of the Martin River Airstrip access road after Bradley Lake HEP construction required submittal of an application for a non-capacity amendment to the project license from the Federal Energy Regulatory Commission (FERC) as well as permits from the U.S. Army Corps of Engineers (USACE) and the Alaska Department of Fish and Game (ADF&G). Concerns There are several concerns related to the Martin River Airstrip Access Road and Airstrip. The concerns include project license compliance, project facilities security, liability related to unknown third parties for a variety of reasons, and project operation and maintenance costs,. The license-related concern is that since both the Martin River Road and Airstrip are permitted and licensed components of the Bradley Lake HEP. It is AEA’s responsibility to maintain both these features in good condition. Failure to do so could result in citations from the FERC, USACE or ADF&G. The security concern is related to the difficulty in monitoring the Martin River airstrip, which is relatively remote and not visible from the power plant area. Small fixed wing or rotary wing aircraft landing there are difficult to see unless a staff person is actually at the airstrip or is driving by the area at the time the intruding aircraft is landing or taking off. This clearly represents an un-controlled entry point to the project and a potential security risk to the Bradley Lake HEP as a whole. The security risk ranges from personal injury to persons attempting to access project facilities for various “innocent” reasons to persons performing acts of vandalism with the intent to render the project inoperable. The third party liability concern is related to potential liability in the case of persons injured or killed in unauthorized use of the airstrip. The airstrip is commonly used by local hunters and guides even though the use is not authorized. This represents a potential liability to AEA and HEA that could run to several million dollars in a legal action should an unauthorized user of the airstrip be injured or killed when using the airstrip. Maintenance of the road and structures and airstrip in serviceable condition will be a sustained annual cost if license compliance is maintained. Some years, major maintenance or replacement will increase the cost and the question is “is it worth the maintenance costs to keep this project feature when it has never been used by the project’? There are practical alternatives available, such as using helicopter or boat transport or simply delaying the departure and arrival of personnel undergoing shift change. Rev 01/17/03 Page 2 of 6 AEA Bradley Lake Hydroelectric Project Martin River Airstrip Access Road Maintenance versus Removal Background The Martin River road was restored in 1996 in order to provide access to the Martin River Airstrip and thus provide aircraft carrying project staff with an alternative landing site, to be used in cases when weather conditions precluded safe landing and takeoff from the primary airstrip. See Aerial Photos of the facilities in question at the end of this document. The Martin River Airstrip is located along the East side of the Martin River delta down stream from the gravel borrow area used during the construction of the Bradley Lake Hydroelectric Project (Bradley Lake HEP). The gravel borrow area was temporarily diked-off from the river but the temporary dikes were left in place after Project construction was completed to function as fish rearing ponds in cooperation with ADF&G. This was an event of opportunity for ADF&G and the department agreed at the time that there would be no liability for dike maintenance or pond operation accruing to AEA and that when the dike finally is breached by the river, it would not be reconstructed. Water from the Martin River percolates through the dike into the ponds, flows through the ponds and exits to the North across the access road at the East end of the airstrip. The Martin River Airstrip Access Road has two bridges and two low-water crossings and traverses the tidal flat/ Battle Creek flood plain to the East of the Airstrip. At times the road is impassable due to flooding and/or high tide. Existing Conditions It is reported that since restoration of the Martin River road, the Airstrip has never been used for the intended purpose. In the winter, the road is not maintained open due to a lack of need for the airstrip in winter and due ice from tidal flooding. Maintenance of the road has been a problem because of changing stream flow conditions related to aggradation of the Martin River stream channel in the river delta/tidal flat adjacent to the Martin River dike, which, when combined with the effects of high tides and ice movement on the tidal flats along the course of this restored road results in flooding and erosion of the roadway. Specifically, the low water crossings, approved by the Federal Energy Regulatory Commission (FERC) and the Alaska Department of Fish and Game (ADF&G), have continually deteriorated since construction and granular material from the roadbed has been eroded and carried onto the adjacent Kachemak Bay tidal flats. In addition, it appears probable that continued aggradation of the streambed along the Martin River dike, if left un-checked, will eventually result in breaching of the dike. This will allow the Rev 01/17/03 Page | of 6 AEA