Regional Impacts Associated with Alternative 4 -- FR/EIS Appendix I (February 2002)
Construction activities resulting directly and indirectly from breaching of the four lower Snake River dams would generate increased business transactions of $2.27 billion, 20,821 temporary jobs, and an increase of $678.8 million in personal income in the lower Snake River study area.
12.1.3 Possible Mitigation and Compensation Costs
Alternative 4--Dam Breaching would also engender other costs to replace services currently provided under existing conditions, including:
- Additional annual power costs of $271 million per year to develop alternative sources of power (e.g., includes the cost of constructing and operating combined cycle gas turbines less the cost of operating the existing system)
- Additional transportation costs of $37.8 million per year to move commodities by rail and/or to truck to more distant barge terminals in the John Day pool, (bluefish asks: Why not Port of Pasco on McNary pool?)
- Additional costs of $15.4 million per year to supply water to irrigators and municipal/industrial users, (bluefish notes: Final FR/EIS found this cost being greater than the irrigated farmlands value and subsequently chose to return the land value to that of unirrigated land, putting farmworkers out of work.)
- Additional costs to retrain workers, which have been estimated at between $45.1 million and $48.1 million,
- Additional costs to mitigate 82 affected communities, which have been estimated to cost between $4.3 million and $12.9 million.
There is no requirement for the Federal government to provide compensation for these costs, but a legislative solution may be developed to provide mitigation and/or compensation.
Project Cost Summary -- FR/EIS Appendix D (February 2002)
Annex X of this appendix provides a summary of the drawdown implementation costs. The costs are summarized by project and by task. The total cost of the recommended implementation action is $881 million. This cost includes required monitoring activities, operation and maintenance costs, and other related costs.
Previous estimates of cost have ranged from a high of approximately $5 billion to a low of approximately $600 million. The high cost features of earlier concepts have been eliminated and replaced with features more appropriate considering the available construction methods. The previous low estimates were revised as more details were developed for stabilization, modification, or mitigation measures.
12. Summary and Conclusions
- Reservoir drawdown and embankment removal must be done during the time period between spill seasons. Spillway discharge to pass the spring freshet and to aid in juvenile migration ends on approximately 1 August. River flows are below 60,000 cubic feet per second (cfs) and remain low until 31 December. The probability of flows in excess of 60,000 increases significantly after 1 January. After 1 January, powerhouse discharge cannot be relied upon to be the sole means of flow passage.
- Breaching of each dam must be done by removal of the embankment section of the dam. Removal of concrete sections requires more time than available.
- Embankment removal can be done with conventional excavation equipment. The quantity and type of equipment anticipated for this work is not extraordinary and is not impossible to secure.
- A key element to making this drawdown concept feasible is the use of existing turbines and passages for primary reservoir discharge. Modifications are required for this equipment to operated under the unusual low-head conditions. (bluefish notes: The DamSense design uses a controlled hydraulic breach and does not require modifications for "unusual low-head conditions".)
- In order to be prepared for reservoir drawdown, the turbine modifications must be done in advance of drawdown. This requires some of the turbine units to be out of service during the previous spill season. The result is that up to 3 units per project may be unavailable during part of the spill season and will result in higher saturated gas levels in the river. (bluefish notes: Such preparation is unnecessary in the DamSense design.)
- The physical effects of migrating sediment may have a negative impact of water intake systems in the river (bluefish notes: Final FR/EIS found the cost of mitigating irrigation to be so high that irrigated farmlands were returned to unirrigated land values.).
- Fish passage is unaffected just prior to drawdown. After drawdown, fish passage will be through the new breach section of each project. During the 90 to 120 day drawdown, adult fish will be collected and transported around the construction and sediment-rich areas. (bluefish notes: Adult fish are not collected in the DamSense design.)
- A major task is the production of rock for riprap bank protection of the railroad and highway embankments that border the river. Approximately 72 kilometers (45 miles) of shoreline requires rock placement. Over 750,000 million cubic meters (1 million cubic yards [cy]) of riprap must be produced, barge transported, and stockpiled prior to drawdown. Underwater stockpile locations have been identified in areas that are considered poor spawning areas under current conditions and will be accessible and above the water surface after drawdown. Rock production and transportation requires continuous operation for up to 3 years prior to drawdown. (The DamSense design, does not forsee the need for this large quantity of riprap material.)
- Several in-water construction activities must be done during non-work window periods. These include the stabilization of bridge piers and the placement of riprap on banks.
- The implementation schedule requires 9 years to implement drawdown. Physical drawdown of Lower Granite and Little Goose reservoirs would occur in year 5 and physical drawdown of Lower Monumental and Ice Harbor reservoirs would occur in year 6. It is unlikely that a more accelerated schedule can be implemented.(bluefish notes:3. Critical Criteria for Design Concepts
Why is a more accelerated schedule "unlikely"? The Appendix D "implementation schedule" holds two years for design and engineering, four years to modify turbines, another year to complete earth embankment removal of Lower Monumental and Ice Harbor, another year to complete bridge pier protections, railroad and roadway damage repair, another year to complete the wildlife habitat management unit modifications, and then a final year to complete the cultural resource protection plan.
The main difference between this plan and that of the Re-evaluation by DamSense is the "No Catastrophic Drawdown" criteria.)
. . .
No Catastrophic Drawdown
The evacuation of the reservoirs will be done at a fixed rate of 0.6 meter (2 feet) per day. A higher rate could cause significant slope failures in the reservoirs, putting highways and railroads out of service. Further detailed evaluation of slope materials may allow some modification of this rate. Drawdown rates may vary during the period of drawdown after considering the location of critical embankments relative to the final water surface. An erosion-based method of embankment removal was not considered a feasible option for this study for reasons discussed further in Section 4.2 of this appendix.
. . .
4.2 Period of Drawdown
Currently, the in-water work window is designated by the National Marine Fisheries Service (NMFS) as December 15 through March 15 of each year. This is the period of time during the year when work activities would impact the least number of fish migrating in the river. However, this time period is not sufficient to perform all the construction activities necessary to produce the new river channel. Furthermore, considering the high probability of excessive river flows during this period, reservoir drawdown must be performed in advance of this period. Otherwise, the risk of catastrophically breaching the embankment is high.
As previously mentioned in Section 3, catastrophic release of water in the drawdown is unacceptable. This can occur when embankment removal is performed using explosives or hydraulic erosion. Once water begins to flow over the embankment, the water erodes the embankment material and very shortly removes the embankment. To breach the embankments while impounding a high head would lead to rapid embankment erosion, uncontrolled erosion, and a high rate of water level drop. Rapid drawdown rates would cause serious damage to railroads and high embankments in the reservoir. The rapid embankment erosion could also harm fish passage. Furthermore, there is significant evidence that an erosion-based method of embankment removal would not achieve complete removal of the embankment material. Uncontrolled hydraulic excavation of the material could result in an unsatisfactory channel configuration that would have obstructed access and be difficult to excavate.
The cost of the implementation is approximately $900 million. Approximately 60 percent of these costs are for modifications in the reservoirs.
A number of modifications have been identified that are not currently considered federal costs. They are included in this study in order to estimate the costs for inclusion in the economic evaluations. Only Congress can authorize project funding for these items. They include private irrigation systems, private water wells and water intakes, private effluent diffusers and utility crossings.
$350 million estimate by DamSense in Re-evaluation of Appendix D by Jim Waddell, John Twa & Anon Fisheries Biologists / Planners, USACE (February 2016)
Through a careful Re-evaluation of the NWW FR/EIS, a revised channel bypass plan for breaching has been designed that costs significantly less (a 70% reduction) than the NWW near-billion dollar proposal and it can be accomplished in half the time.
The keys to accomplishing a cost and time efficient breaching of each dam are as follows:
- Very little modification to the power house is needed. The NWW proposal involved significant alterations to the six turbines that even their own data showed was unnecessary to safely drawdown the reservoir.
- Allow the river to do the majority of the embankment removal. The NWW proposal was to mechanically excavate the entire earthen embankment and only allow the river to breach the cofferdams, although it appears that more hydraulic removal of material is required than assumed. Hydraulic breaching has been used numerous times in the Pacific Northwest in the years since the FR/EIS was written and new technology exists to model hydraulic breaching in a safe and predictable manner as was done in this updated plan.
- River channelization can be accomplished using materials already in place at the dam. During dam construction, the natural river channel was successfully routed around the concrete structure without the levees proposed in the FR/EIS.
- Fish handling is unnecessary. Dam breaching will take place at a time when few anadromous fish are present in the river. Hydraulic conditions through the breached embankments will be favorable to fish passage, just as they were during dam construction.
- Minimal reservoir embankment actions are necessary for road/railroad protection and repairs. The NWW proved this during the 1992 drawdown test. In the FR/EIS, NWW planned to spend one hundred times more money on repairing damages to roads and railroads than drawdown actually caused. Drawing the reservoir down at a slower initial rate, as this Re-evaluation recommends, will further reduce the minimal damage that occurred in the 1992 test.
(bluefish notes: FR/EIS 2002 Response to Comments, "the exact extent of embankment failures is hard to predict due to the rapid drawdown rate of 2 feet per day. ... A slower drawdown is not reasonable if dam breaching is to occur within a work window that has the least impact on migrating salmonids.")
- Lyons Ferry Hatchery should not be modified as the NWW's plan proposes.
- Since Channel Bypass was selected and this plan simply improves on it at lower cost, this plan is consistent with the existing Environmental Impact Statement for the overall project.
Many people are familiar with the Seventh Generation philosophy commonly credited to the Iroquois Confederacy but practiced by many Native nations. The Seventh Generation philosophy mandated that tribal decision makers consider the effects of their actions and decisions for descendents seven generations into the future. There was a clear understanding that everything we do has consequences for something and someone else, reminding us that we are all ultimately connected to creation.