Archives 2019

Review of ‘Unusual’ 2018-19 Water Year

To say it has been an unusual year is perhaps an understatement.

The 2018-19 water year ended on Sept. 30 (a water year runs from Oct. 1 to Sept. 30 of the next year) and it was a year marked by heavy and frequent rain storms, floods, planting delays, bone-chilling winter temperatures, and even “bomb cyclones,” among other anomalies in terms of weather and water.

While this part of Nebraska was largely spared from the calamities that befell other parts of the state (except for the deluge that caused flooding along Turkey Creek in Kearney and the Wood River flooding that struck several other central Nebraska towns), it has also been an unusual year for the water supply at Lake McConaughy.  While total water year inflows were above average, the 1.19 million acre-feet barely cracked the Top 20, finishing at 19th highest in the reservoir’s history.  (An acre-foot is the volume of water that would cover one acre with 12 inches.)

But it was the inflows during the summer months that made the water year unusual.  Normally inflows are highest in October and then in May and early June.  In fact, from October of last year through May, inflows were pretty much in line with the normal monthly averages.

Then came summer.  Inflows to Lake McConaughy during June were twice the normal amount; more than two and a half times normal in July; and 348 percent of normal in August.  In fact, the 162,843 acre-feet (a-f) that flowed into Lake McConaughy in August was the highest monthly total for the year.  Historically, as one would expect in a snowmelt-fed basin, inflows during August are near the low point for the year, trailing only July (median inflows of 46,815 a-f in August and 45,718 a-f in July).

Several factors converged to yield this outcome.  First, mountain snowpack in Colorado and Wyoming was above average in all three basins – the upper and lower North Platte River and the South Platte River – that affect river flows into Nebraska.  The subsequent runoff, particularly in the North Platte Basin in which Lake McConaughy is located, entered U.S. Bureau of Reclamation (USBR) reservoirs in Wyoming that were already holding plentiful supplies of carryover storage from the last year.

Second, frequent precipitation across much of the Platte Valley suppressed demand for irrigation.  Rainfall during the growing season (April through September) collected in Central’s Holdrege gauge totaled 25.44 inches, compared with the 20-year average of 18.63 inches and 19.0 inches since 1957.

However, the frequency of precipitation perhaps played a more significant part in reducing irrigation demand than the amount of rainfall.  Few weeks went by this summer without some amount of rain, which was often enough to dissuade an irrigator from starting his pivot or opening the gates on his pipe.

And finally, a mid-July tunnel collapse on an irrigation canal that delivers water to the Goshen Irrigation District in Wyoming and the Gering-Ft. Laramie Canal in Nebraska’s Panhandle, prevented delivery of water to about 107,000 acres in the two states.  With abundant water already in storage and the approaching need to make room for next year’s inflows, releases from the USBR reservoirs that normally would been diverted into the two canals continued downstream to Lake McConaughy.

Lake McConaughy’s lowest elevation (3,252.5 feet above sea level) during the 2018-19 water year actually occurred on Oct. 1, 2018, the first day of the water year.  The reservoir’s peak elevation occurred on July 15 at 3,260.1 feet, declining to elevation 3,257.9 in mid-August and currently stands near elevation 3,259.0, about six feet below full elevation.

And here’s an interesting observation:  Lake McConaughy’s elevation of 3,258.7 feet on Aug. 31 was the same as it was on Aug. 1.  A check back through the data reveals that that has never happened in the reservoir’s 79 years.  While August’s inflows were well short of a record amount, the monthly total did rank fifth behind 2010, 1973, 2011 and the record of more than 328,000 a-f in 1983.

So if you’ve noticed quite a bit more water flowing down the Platte River this summer, that’s the explanation.  A lot of water going into Lake McConaughy, and once it was released, not much demand for it to be diverted into the many irrigation canals along the central Platte.

With long-range forecasts calling for a cold and wet winter, one wonders what Mother Nature has in store for Nebraska in the new water year.

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2019 Legislative Session in Review

Much was written and spoken about what the Nebraska Legislature did and did not accomplish during the 2019 session, which adjourned on May 31.

Tax reform and efforts to substantially lower property taxes were at the top of the list of “things to do” next session, as efforts in the Legislature to reach agreement came up short.  Legislation to enact new business tax incentives (to replace the Nebraska Advantage Act, which expires at the end of 2020) became entangled with property tax relief last session and a solution that would satisfy enough senators for either to pass proved elusive.

However, it’s not my intent to add to the debate over taxes or business incentives; instead I’ll use this space to discuss a number of bills pertaining to water and natural resources that were either passed with little fanfare, or (appropriately and thankfully, in our opinion) failed to advance.

The bills were not as controversial, but the lack of controversy does not diminish their importance to those who will be –or won’t be – affected.

LB48, introduced by Sen. John Stinner of Scottsbluff, changes provisions related to a finding of sufficient cause for non-use of a water appropriation.  The new statute, which passed final reading 43-0 and was signed into law by Gov. Ricketts, allows contracts under any crop reserve program to be extended to 30 years by providing for sufficient cause for nonuse of water rights.  In other words, acres enrolled in such federal, state or Natural Resources District programs can maintain their water right without threat of cancellation for non-use.

For instance, the federal Conservation Reserve Enhancement Program (CREP) is designed to reduce the amount of water consumption from irrigation activity as well as the introduction of agricultural chemicals and sediment entering the waters of the state from agricultural lands and transportation corridors.  Enrollees in CREP are protected from losing their water appropriations for a longer period than was provided under current state law.

LB294 and LB298 were both budget bills; both contained provisions that were in the governor’s original proposal that the Legislature left intact.  After a few years of seeing reductions in the mainline budget bill, the Water Sustainability Fund contained within LB294 will receive its full allotment of $11 million during the next biennium, enabling the Natural Resources Committee and the Department of Natural Resources (DNR) to continue to build upon the successes they’ve had with various projects intended to enhance the state’s ability to achieve sustainability of our water resources.

And in LB298, the ability for DNR to receive grants from the Nebraska Environmental Trust Fund was continued, which is an important component of DNR’s efforts to fund water projects in the state.

LB302, introduced by Sen. Dan Hughes of Venango, proposed to merge the State Energy Office with the Department of Environmental Quality and rename the agency the Department of Environment and Energy.  The bill passed final reading on a 45-0 vote and was signed with an emergency clause (meaning it takes effect immediately) by Gov. Ricketts.

Mostly intended as an efficiency measure, one important aspect of the merger, at least to those in the water resources field, was authorization the agency to assume responsibility for the “dredge-and-fill” permitting process, pending agreement between the federal government and the state.  This development has the potential to speed the permitting process and allow projects to proceed more quickly without sacrificing environmental quality.

A couple bills that failed to advance from their respective committees included LB368, which would have legislatively eliminated the “over-appropriated” designation of river basins, sub-basins and reaches and require the DNR to manage dams in Nebraska as flood control structures, effectively preventing them from filling past 80 percent before a certain date.

Sen. Hughes, in his opening at the hearing on the bill, explained that he introduced the bill to provide the Natural Resources Committee, of which he is chairman, with information about why water is managed as it is today and to help the committee members better understand what the fully and over-appropriated designation means.  He also intended the bill to serve as an opportunity for education, background and context to discussion of water legislation.

He closed his testimony by saying that the hearing was a “… good exercise for the committee to understand the challenges that we have in Nebraska, but there’s been a lot of work in this committee before we ever got here.  Any changes that (the Legislature) makes in water policy should be taken very slowly, very deliberately, and very cautiously.”

And last, LB655 was introduced by Sen. Justin Wayne to change provisions of Nebraska’s fencing laws.  The bill, which received little or no support in the Agriculture Committee hearing, would have turned the state’s fencing statutes upside down by eliminating the practice of sharing financial responsibility for construction and maintenance of division fences currently found in statute.

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Spring has sprung (hasn’t it?), and water’s flowing downhill

Spring has sprung (hasn’t it?), and water’s flowing downhill

During Central’s April board meeting, Hydraulic Project Operations Manager Cory Steinke engaged board members and everyone else at the meeting in an exercise to illustrate the complexity and difficulty of managing water supplies.

Each participant was given a stack of pennies that represented the existing – and future – water supply in storage at Lake McConaughy.

The point of the exercise was to complete a four-year cycle of inflows and releases without 1) running out of pennies (water); and 2) leaving insufficient space for additional pennies (inflows) resulting in a “spill” of valuable water.  (A “spill” is a release of excess water from a reservoir.)

During the exercise, Steinke was repeatedly asked for more information pertaining to various snowpack conditions, irrigation demand, upstream storage reservoir conditions, weather forecasts, etc.  But a crystal ball was not part of the game, just as water managers usually cannot see clearly very far into the future.  They must rely on the best available information – both short-term and long-term – on which to base their decisions and even the best, most recent information, can be subject to rapid change.

Operational projections begin with known quantities of water in storage at the beginning and end of any particular cycle.  Despite having access to the latest forecasts, any unexpected changes to any of the numerous factors that influence water management operations could leave the participants “penniless,” or at the other end of the spectrum, having too many pennies in the bank.

One need look no further than the recent events afflicting eastern and northeastern Nebraska and western Iowa.  The flood damages were the result of a series of unlikely events occurring simultaneously, creating a scenario that overwhelmed manmade dikes, dams and operational plans and caused creeks and rivers to swell out of their banks.

A coincidence of “unlikely events” is not the same as “impossible events;” even planning that prepared for “unlikely events” and “maximum probable floods” was overcome by the capriciousness of weather and Nature’s unrelenting power.

While flooding along the Platte River did not occur in central and western Nebraska, spring is the time of year when water managers keep particularly close watch on conditions in the upper Platte River basin.

The U.S. Bureau of Reclamation, which manages a series of reservoirs on the North Platte River in Wyoming and monitors snowpack/snowmelt conditions in the North Platte and South Platte drainage basins, recently released its projections for runoff.

The April forecasts indicate the spring snowmelt runoff will be above average.  Total April through July runoff in the North Platte River Basin above Glendo Dam in Wyoming is expected to be 1,005,000 acre-feet (a-f) which is 111% of the 30-year average.

As of March 31, storage content in the North Platte Reservoirs was 1.8 million a-f, which is 110% of the 30-year average.  The total conservation storage capacity of the North Platte Reservoir System is approximately 2.8 million a-f.  At this time, the Bureau is not anticipating a spill of water from Pathfinder Reservoir.

In the South Platte River basin, snowpack conditions are currently at, or slightly above, normal for early April.

Prior to the projections, Central had noticed the increasing snowpack and began making adjustments to water operations to leave space in Lake McConaughy for any extra water released from the upstream reservoirs.

However, the South Platte River remains, as always, a wildcard.  With only minimal amount of off-stream storage capability in Colorado, the South Platte remains susceptible to rapid snowmelt runoff and heavy spring rains that could cause high-water events in western and central Nebraska after it joins with the North Platte River east of the City of North Platte.

Central will continue to monitor developments in the North and South Platte River basins this spring and is tailoring operations to developing conditions, including precipitation forecasts for April and May that call for increased chances for above normal precipitation throughout most of the Platte River Basin.  Lake McConaughy has no designated flood pool (an amount of space in a reservoir designed for flood control used to regulate floodwaters), other than gradually rising restrictions on maximum elevation during the spring, but the reservoir has been operated during high-flow periods when necessary to mitigate downstream flooding that is often the result of high South Platte River flows.

But as demonstrated by recent events, Mother Nature sometimes has plans of her own that overwhelm human efforts to manage our rivers and streams.

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