Minimum Flow For Arkansas White River Tailwaters
(Last updated on 7/16/2013)
Q: What is minimum flow?
A: Minimum flow is the constant release of a small specified volume of water from below each dam during non-generation or non-flood releases. This helps increase fish and spawning habitat as well as temperature control to benefit the trout fisheries in the river sections below the dams. The flows are designed to mitigate flows which fall below historic averages—flows which result from the Corps of Engineers shutting off water at the powerhouses.
Q: How did the concept develop?
A: The concept of minimum flow came about as a result of the dam construction on the White River system. Before the five U.S. Army Corps of Engineers project dams were built beginning in about 1941 and ending in 1965, the White River was a big uncontrolled river. The dams were a consequence of the catastrophic flooding of the lower Mississippi River in 1927. This flood affected the White River as well. The railroad roundhouse at Cotter was destroyed by the flooding, and flows at Calico Rock exceeded 250,000 cfs. As a consequence, Congress passed several major flood control acts (The Mississippi Flood Control Act of 1928, and Flood Control Acts of 1938, 1944, 1946, and 1954) resulting in numerous dam building projects, including the White River dams.
The newly constructed dams meant a federal agency had the ability to store flood water runoff in the reservoirs and release it later during a non-flood event. The stored water could also be used to release through hydropower facilities for "free" electricity. This also meant the Corps could now cut off releases below the dams resulting in flows which fell below historic averages. The White River fisheries got a double whammy: 1) the nature of the river segments below the dams changed forever to cold water environments, destroying a world famous smallmouth fishery which was now mitigated with stocked trout, and 2) the river was reduced to a trickle at times as flows were curtailed or shut off at the dams.
As the state trout fishing program became more popular, Arkansas Game and Fish Commission trout biologists argued the need to continue to mitigate the loss of flows below the dams with some water for trout. In the mid-1990s, under the leadership of fisheries chief Allen Carter, assistant chief Larry Rider, and trout biologist John Stark, the commission moved with major studies to undertake instituting minimum flow. Aerial surveys, computer assisted modeling from the TVA, dye studies, and other scientific techniques were used to determine the best beneficial flows for trout without substantially impairing anglers ability to wade fish during minimum flow releases.
Chiefly because of the senate leadership of Tim Hutchinson (AR), the Water Resources Acts of 1999 and 2000 allocated monies for the Corps of Engineers to conduct studies to determine if minimum flow was feasible and economically justifiable.
The Corp's report was finished in the summer of 2004 and presented to Congress with the conclusion that minimum flow would be a "benefit to the nation" and was justified economically. The Corp's chief, however, recommended minimum flow only for Bull Shoals and Norfork tailwaters. A lot of politicking went on in the final reallocation report. Arguments had previously ensued over the methods by which the numbers in the report were determined. Southwestern Power Administration heavily influenced the process in favor of their power interest. One of the political tradeoffs was AGFC foregoing insistence on minimum flow for Beaver tailwater if Southwestern Power would not object to the allocation of water for the Beaver trout hatchery. The hatchery had been approved in legislation in the 70s but had never been funded. In the end, the hatchery outflow could provide some minimum flow (18 CFS) in the tailwater. All the parties seemed agreeable to the compromise, although in my mind 18 CFS is a long way from the 150 CFS recommended flow by AGFC biologists. The gravel spawning area for brown trout around Parker Bend would benefit enormously from the higher rate of flow in the late fall of the year. The tailwaters of the Little Red were also left off of minimum flow in the final deal. Missouri Department of Conservation took a wait-and-see approach and decided to make their own arrangement for minimum flow below Table Rock dam, instead of having it included in this minimum flow legislation.
Q: What is the status of minimum flow now?
A: Minimum flow below Bull Shoals dam began on July 4, 2013. This is what it looked like on the Corp's flow gauge. Flow was actually varying between about 700-900 cfs. Watch for refinements as the project moves forward.
Minimum flow below Bull Shoals dam first appeared on the stage graph as illustrated above.
Minimum flow is now a permanent feature of the tailwater landscape whenever generation is "off." The Corps has estimated it needs to release about 600 cfs through one generation when all other generation is off to meet the 800 cfs target flow. There is some leakage at the dam which provides the 210 cfs.
|Bull Shoals||current minimum 210 CFS||target minimum 800 CFS||increase of 590 CFS|
A minimum flow of about 600-650 cfs from one generator raises the tailwater stage level below the dam about 1.4 feet over the previous non-generation level. Minimum flow release shows up on the generation cfs and power graphs (as about 6-7 mw) and on the tailwater stage graph.
Minimum flow below Norfork dam first appeared on the tailwater stage graph as illustrated above. The flow now is listed in a separate graph on the Corp's Water Management website.
Minimum flow started on Norfork tailwater September 12, 2013 and is now a permanent feature of the tailwater landscape whenever generation is “off.” The Corps has estimated it needs to release about 185 cfs through a new installed siphon when generation is off to meet the 300 cfs target flow. The outflow of the Norfork Hatchery provides the 115 cfs.
|Norfork||Current minimum 115 CFS||Target minimum 300 CFS||Increase of 185 CFS|
The 185 cfs from the siphon raises the tailwater stage level below the dam about 6.8 inches over the previous non-generation level. Minimum flow release does not show up on the generation cfs and power graphs—only on the tailwater stage graph.
Minimum flow siphon at Norfork Dam is now in operation.
Be safe while wading, and be aware water from generation increases will come up faster than you are used to seeing. Don’t wade in areas where rising water will cut off your retreat. Wade safely, retreat safely.
From earlier updates:
[April 2013] Initial testing of the siphon at Norfork dam was being done March of 2013. As of April 2, 2013, according to an update I received from Glenn Proffitt, Minimum Flow Project Manager with the Corps, some issues were being resolved with the siphon at Norfork dam. Once the subcontractor finishes up his final checklist of items and hands the work over to the Corps, it will notify AGFC by letter that the siphon is in operation.
[December 2012] The Corps of Engineers and Arkansas Game and Fish Commission signed the final partnership agreement the end of 2011. AGFC has been relocating some of the park facilities that will be affected on the lake side of Bull Shoals and Norfork lakes. The Corps began installing the siphon through Norfork dam the spring of 2012. Capture and release of minimum flow was expected on Norfork tailwater by the end of 2012. Bull Shoals will begin minimum flow after facilities are relocated and flood storage can be captured in 2013.
[February 2010] Legislatively, the project was completed with the passage and signing of H.R. 3183 in October of 2009.
The Army Corps of Engineers in Washington signed the Record of Decision approving the minimum flow study in January of 2009, almost ten years after the study was authorized by congress.
In January of 2010 Arkansas Game and Fish Commission signed a memorandum of understanding with the Army Corps of Engineers. AGFC will work on moving park facilities on the lake side which will be impacted by minimum flow storage.
Engineering, design and construction is beginning. Construction for Norfork dam involves a siphon and the bid has been let for construction. Capture and storage of allotted water must take place before flows can begin. Minimum flow is expected to begin there by 2011-12. Bull Shoals minimum flow will take perhaps a little longer.
As an historical note, since water allocation for Bull Shoals minimum flow will come out of the flood pool, as of June 21, no flood pool storage was available in year 2006, even if the Corps could have begun capturing it. Fifty percent of Norfork's allocation comes out of the conservation pool. It is estimated that sufficient storage will provide for minimum flow about 80% of the time (or 8 out of 10 years.)
[December 2005] House Bill 2419 became law on 11/19/2005. It gives the go-ahead for the Corps to implement minimum flow on Bull Shoals and Norfork tailwaters according to the funding parameters set forth in the bill and pending completion of an environmental impact study due out in July 2006. Below is the language of the bill that pertains to White River minimum flow and the hatchery below Beaver Dam.
Energy and Water Development Appropriations Act, 2006 (Enrolled as Agreed to or Passed by Both House and Senate)
SEC. 132. WHITE RIVER BASIN, ARKANSAS- (a) MINIMUM FLOWS- (1) IN GENERAL- The Secretary is authorized and directed to implement alternatives BS-3 and NF-7, as described in the White River Minimum Flows Reallocation Study Report, Arkansas and Missouri, dated July 2004.
(2) COST SHARING AND ALLOCATION- Reallocation of storage and planning, design and construction of White River Minimum Flows project facilities shall be considered fish and wildlife enhancement that provides national benefits and shall be a Federal expense in accordance with section 906(e) of the Water Resources Development Act of 1986 (33 U.S.C. 2283(e)). The non-Federal interests shall provide relocations or modifications to public and private lakeside facilities at Bull Shoals Lake and Norfork Lake to allow reasonable continued use of the facilities with the storage reallocation as determined by the Secretary in consultation with the non-Federal interests. Operations and maintenance costs of the White River Minimum Flows project facilities shall be 100 percent Federal. All Federal costs for the White River Minimum Flows project shall be considered non-reimbursable.
(3) IMPACTS ON NON-FEDERAL PROJECT- The Administrator of Southwestern Power Administration, in consultation with the project licensee and the relevant state public utility commissions, shall determine any impacts on electric energy and capacity generated at Federal Energy Regulatory Commission Project No. 2221 caused by the storage reallocation at Bull Shoals Lake, based on data and recommendations provided by the relevant state public utility commissions. The licensee of Project No. 2221 shall be fully compensated by the Corps of Engineers for those impacts on the basis of the present value of the estimated future lifetime replacement costs of the electrical energy and capacity at the time of implementation of the White River Minimum Flows project. Such costs shall be included in the costs of implementing the White River Minimum Flows project and allocated in accordance with subsection (a)(2) above.
(4) OFFSET- In carrying out this subsection, losses to the Federal hydropower purpose of the Bull Shoals and Norfork Projects shall be offset by a reduction in the costs allocated to the Federal hydropower purpose. Such reduction shall be determined by the Administrator of the Southwestern Power Administration on the basis of the present value of the estimated future lifetime replacement cost of the electrical energy and capacity at the time of implementation of the White River Minimum Flows project.
(b) FISH HATCHERY- In constructing, operating, and maintaining the fish hatchery at Beaver Lake, Arkansas, authorized by section 105 of the Water Resources Development Act of 1976 (90 Stat. 2921), losses to the Federal hydropower purpose of the Beaver Lake Project shall be offset by a reduction in the costs allocated to the Federal hydropower purpose. Such reduction shall be determined by the Administrator of the Southwestern Power Administration based on the present value of the estimated future lifetime replacement cost of the electrical energy and capacity at the time operation of the hatchery begins.
Congressmen Marion Berry (District 1) and John Boozman (District 3) worked extremely hard to get legislation passed for the project. Their efforts should be applauded. A lot of Arkansas Game and Fish Commission personnel and Corps of Engineers Minimum Flow Project Manager Mike Biggs worked tirelessly. I know Mike Biggs took a lot of heat for trying to be fair with the project oversight. Some of the Game and Fish personnel who initiated the studies have since retired or gone on to other jobs. A few fishermen got involved along the way also. This was a big effort.
Q: How will minimum flow affect wade fishing?
According to p. 28 of the Corp's final reallocation report, minimum flows will be :
|Bull Shoals||current minimum 210 CFS||target minimum 800 CFS||increase of 590 CFS|
|Norfork||current minimum 115 CFS||target minimum 300 CFS||increase of 185 CFS|
The current minimums account for leakage from the dams and the Norfork hatchery. The 590 CFS on Bull Shoals is equivalent to less than about one fifth of a unit. The gained increase in wetted areas is the significant thing for both fisheries. It's an increase of between 33 for Bull Shoals tailwater and 53% for Norfork tailwater. This is a significant habitat increase for the fish, and it will result in less exposed gravel to superheat in the summer time keeping water temperatures cooler well down stream.
At the levels proposed in the reports and recommended by Game and Fish, minimum flow will have negligible impacts on wade fishing. Game and Fish has proved this with aerial fly over surveys of wade anglers conducted during minimum flow tests. During test flows in June of 2001, I floated the tailwaters below Beaver and Bull Shoals dams. The Corps ran minimum flow on Bull Shoals tailwater for three days in order to get accurate evaluation of the effects downriver. I saw anglers wade fishing in the usual spots, and all I talked to were happy with the flows and the fishing. Water levels were an estimated 8 to 10-inches over "dead low." One of the big benefits I saw was that bigger brown trout were coming up out of the deep holes and positioning on the shallower edges. They had more habitat available to them, and they obviously were taking advantage of it.
Will minimum flow make the tailwaters more dangerous for wade fishermen? The tailwaters are an inherently dangerous place to wade fish—period. Minimum flow should not change that for the better or for the worse. Wade anglers will still have to practice safe wading and be aware of flow increases under generation and flood water releases. As far as the fishing goes, both boating and wading anglers will benefit. Having done both wade and drift boat fishing over the years on the White and having seen extreme low water and high water years, I'm excited about the improvements to the fisheries it will bring. The impact to the health of the fishery will be substantial. This will translate into more habitat, more success in spawning, and down the road a number of years, look for bigger fish and better fishing. Remember, fish live in water and like lots of it.
Q: Where can I get more information?
A: The Corps of Engineers Website contains the Corp's planning document on minimum flow water reallocation from 2008.