Tracing the history — and potential future — of cut backs to farmers’ well pumping | TheFencePost.com

Tracing the history — and potential future — of cut backs to farmers’ well pumping

Tyler Silvy
tsilvy@greeleytribune.com

Long before rain gauges and streamflow sensors, pinyon pine trees kept records of wet and dry years tucked away in their trunks.

Connie Woodhouse, a professor in the School of Geography and Development at the University of Arizona, seeks out those secrets by first comparing the existing streamflow data from the past 100 years with tree rings.

From there, it's a simple, almost elegant process. Just like the scientists studying the arctic using ice cores, those studying tree rings bore into the trunk and punch out a pencil-sized core dating back hundreds of years.

Wide rings indicate wet years. Narrow? Those are dry.

The rings from 2002 in Colorado are narrower than any since 1685, Woodhouse found in one of her studies.

Nearly 320 years passed between 1685 and 2002. But today, strict water rationing for Weld County farmers is based on the bone-dry year of 2002, an event so rare that it last happened almost 100 years before the U.S. became a nation.

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Because rationing of farmers' supplemental well pumping comes from those 2002 levels, groundwater has nearly drowned residents' basements and destroyed portions of prime farmland. All of it, residents and farmers say, demonstrates the unnatural balance of today's water policy, history and Mother Nature.

At the onset of flooding fears in and around Gilcrest, Colo., when water began pouring into basements, the Groundwater Technical Committee was formed.

Growing out of the South Platte Roundtable, itself started in 2005, the Groundwater Technical Committee's job was to deal with high groundwater issues in some way.

After nearly four years of study, that committee released its draft recommendations on Feb. 7. It's a contentious document for some, but both proponents and opponents agree on one thing: There's no simple, elegant answer.

History lesson

It might sound counterintuitive, but the South Platte River flowed year-round after farmers began diverting it for irrigation via ditches in the 1800s.

Crops don't soak up all of the water they're given. On average, they drink about half. The rest, at least the portion that doesn't evaporate, soaks deep into the ground.

It doesn't stay there. Instead, the water slowly makes its way back to the river. That's called return flow, and return flows made the South Platte flow all year.

In periods of drought, some farmers found they could install wells to recapture the water their crops didn't drink.

Some were dug in the early 1900s, and many more followed during the dry 1930s. After the 1950s, when well technology had advanced and farmers suffered another years-long drought, well proliferation exploded. By the late 1970s, there were thousands along the South Platte River.

Along the way, people raised concerns.

By the late 1960s, it was established science that wells hurt return flows, and therefore, they were hurting downstream water users who had legal rights to divert water from the South Platte.

The Water Rights Determination and Administration Act of 1969 sought to force wells into the prior appropriation system. In Colorado, if you made beneficial use of water from the South Platte in 1880, that gives you the right to restrict use by anyone upstream with a water right after 1880 if you're short of water.

Wells are trickier. Unlike surface water, which farmers can simply stop diverting, the underground depletions from well pumping take time — weeks, months and even years — to affect the river.

So despite being put in the priority system, wells can't simply pump based on their priority date, because there's no guarantee they'll be in priority by the time the pumping affects the river.

The state engineer's office put together a plan after the 1969 legislation, but it wasn't fully approved until 1973, after a trip to the Colorado Supreme Court. Legislation required a court decree or augmentation plan for well pumping. Augmentation plans deal with restoring at least some of the water farmers pump out of the ground.

But it also allowed the state engineer to administer substitute water supply plans, approved yearly, that called for the replacement of 5 to 10 percent of well pumping depletions to prevent harm to other water rights holders.

That worked fine until 1977, another year Woodhouse circles as being on par with 2002 and 1685 in terms of overall dryness.

"If the drought continues into 1978, it is certain that senior surface water rights will be materially injured by junior well pumping since augmentation on the basis of 5 percent of pumping will not provide sufficient water to augment stream depletions," according to a 1978 Bureau of Reclamation study on pumping impacts along the South Platte.

The drought didn't continue, but that doesn't mean water users forgot.

"Some people think the well pumping effects were masked by (relatively wet years in the 1980s and 1990s)," Frank said. "There were organizations that warned the state, providing letters and saying, 'Hey, we need to work this out.'"

Then in 2002 came the massive drought.

"You couldn't ignore it."

The blowback

The 2002 drought fundamentally shifted the way farmers around Gilcrest manage water, thanks to the fear it stoked among some water rights holders.

Rather than plan for one such occurrence every 317 years, those water rights holders now demand that farmers around Gilcrest plan for it every year, for seven-straight years.

"It's a worst-case scenario," said Dave Nettles, division engineer in Greeley, Colo., for the state engineer's office. "It assures folks on the river (they'll have water) even in the worst imaginable scenario."

The Central Colorado Water Conservancy District, a cooperative taxing district that manages water use for its users covering portions of Weld, Adams and Morgan counties, has water court-based augmentation plans — signed after 2002 — with just such requirements.

When a Central well operates, Central must prove it will have enough augmentation water to replace 100 percent of the depletions from groundwater pumping over the next seven years if each of the next seven years are as dry as 2002.

"The pendulum has swung too far," said Randy Ray, the executive director of the Central Colorado Water Conservancy District.

The result for some Weld County farmers is their wells can't consistently be used even for their original purpose — to combat drought. The 2012 drought year dried up the South Platte, but unlike in 2002, Weld farmers had to dry up hundreds of acres of corn because they couldn't use wells to supplement their own senior surface water rights. Non-farmers are feeling the effect too. Decades of well pumping artificially lowered the water table in and around Gilcrest. Houses sprang up, complete with basements. Many made their homes here in the 1970s. Even in 2006, when Glenn Fritzler built his house near his famous Fritzler Corn Maze, the builder said no sump pump or French drain was necessary for the basement.

Near the turn of the century, that changed after the groundwater began to rise.

About the same time as the 2002 drought year, a Colorado Supreme Court case — the Empire Lodge case — took away the state engineer's power to administer substitute water supply plans.

Then came legislation in 2002, 2003 and 2004 that required all wells to have a court-decreed augmentation plan by Jan. 1, 2006.

After that, thousands of wells were shut down.

Gone were the 5 to 10 percent replacement requirements. Farmers were staring down the barrel of 100 percent replacement, plus making good for past depletions, plus projections based on the driest of dry years.

Gone, too, was a so-called gentleman's agreement that kept senior water right reservoir owners from placing a call on the river, as groups cooperated to provide water when necessary and reservoirs agreed to fill from the top down. It just made more sense, some said.

Now, there's a call on the river throughout much of the year, which has the effect of further curtailing well pumping.

Without regular pumping, more basements are inundated each year, and residents spent hundreds of thousands of dollars on repairs and French drains and sump pumps to keep the water out.

Farmers, meanwhile, have seen potatoes and other underground crops rot in their fields, and high groundwater has left splotches of crusty salt deposits in areas, rendering portions of some fields useless.

But change won't come easy.

First, Central would need to establish that the formulas used to predict underground water flows to the river don't match reality. Doing so would require an expensive study by a consultant who probably doesn't exist in Colorado, Ray said.

"I don't think you can get an engineer that practices here to come and work for you, to do something that's so out of the realm of ordinary, because then they're going to be labeled as a renegade," he said.

So, Ray said, they pick around the edges with things such as a recent helicopter study that used sonar data to shed light on the geological makeup of the aquifer around Gilcrest. Final results will be out this spring, but that still won't be enough.

"If we want to spend a million dollars to develop a bunch of analytical models to say what we agreed to in our decree was (based on outdated science), we would still have to prove it to everybody on the river that holds a water right," Ray said. "They would all object to it (in court), and we would have to prove to them our science was right, and it would cost us millions more."

Back from the dead

Wells around Gilcrest, Platteville and LaSalle are generally pumping more water than any time in the past decade, and that's thanks to a solution that's a blessing and curse, depending on who's talking.

It's called artificial recharge, and it has existed in some form for decades. The first official artificial recharge project took shape in 1974, but the phenomenon has exploded since the late 1990s through today, as strict regulations for well pumping required more and more replacement water.

Artificial recharge can be done in existing ditches, where ditch owners will bring water in, dam up the ditches and allow water to seep into the ground.

Often, shallow ponds are dug for the purpose, and owners of these recharge ponds ensure the bottoms of the ponds are sandy and porous — the better to make sure water seeps down quickly so they don't have to discount evaporation.

Every drop that makes its way underground via artificial recharge earns the owners of those projects water credits that can be used to pump later, say, in the heat of the summer, or at the end of the growing season when the rains refuse to come.

Nettles keeps track of recharge amounts in acre feet. One acre-foot of water is enough to cover an acre of ground in a foot of water, and it's enough to satisfy two households for a year.

Central peaked in 2015, recharging 30,000 acre-feet of water. From Denver to the state line, along the South Platte, artificial recharge reached 320,000 acre-feet via 500 recharge projects. There are more than 800 such projects along the South Platte today.

Because of past depletions and the need to project seven years of bad luck equal to the driest year in modern history, Central's well pumpers don't get to pump amounts equal to recharge, let alone what they used to pump. The best years since 2000 have allowed farmers to pump 50 percent of their historic pumping amounts.

Perhaps that's why some say artificial recharge causes its own set of problems. If shutting down wells contributed to rising groundwater, dumping more water into the ground while wells were shut down or cut back also contributed, the argument goes.

Central's largest artificial recharge project, the Haren Recharge, consists of 80 acres of ponds northwest of Gilcrest. In the years since Central began filling those ponds, the groundwater level in the area has risen more than 20 feet.

Meanwhile, groundwater continues to saturate fields and flood basements, reaching its highest level on record in the fall of 2017.

Nettles said legislation that passed a few years ago now allows his office to examine unintended consequences of planned recharge sites and make recommendations to the water court that is charged with approving those plans. Nearby houses with basements, for example, might raise red flags.

Ray has heard the criticism.

"I've had a lot of them tell me, 'Why do you guys go through this nonsense?'" Ray said. "'If you just let us pump our wells, we can take care of the water table problem.'"

Central officials are now eying a site near Wiggins for a multi-million-dollar artificial recharge project that will dwarf the Haren project.

It's called the Walker Recharge Project, and it's named after former Central Colorado Water Conservancy District board member Robert W. Walker.

Central already has filed a water right application for the project, which has yet to be built. The organization will likely ask its members to approve a tax increase this November so Central can take on debt to build the estimated $15 million project.

The Walker Project alone will allow Central to recharge a maximum of 30,000 acre-feet per year, matching the organization's highest yearly recharge total from all of its dozens of smaller recharge sites.

Ray said the plan is to continue recharging just as much in the Gilcrest area, but the Walker project could also provide an out when it comes to recharge-based tension.

"There's a lot of pressure about recharge projects in the Gilcrest area," Ray said.

— Tyler Silvy covers government and politics for The Greeley Tribune. Reach him at tsilvy@greeleytribune.com. Connect with him at Facebook.com/TylerSilvy or @TylerSilvy on Twitter.

» Problem solvers

After nearly four years of study, the Groundwater Technical Committee on Feb. 7 released its draft recommendations for dealing with high groundwater in and around Gilcrest. Below, we go over select solutions and potential drawbacks for each. Drawbacks are either from the Tribune’s own reporting or from the Groundwater Technical Committee’s report.

De-watering — One of the key solutions, de-watering uses a well or series of wells to pump out high groundwater and take that water directly to the river rather than waiting for it to slowly creep to the river on its own. A pipeline is one option, and it’s one Gilcrest is using with a de-watering well recently constructed at its sewage treatment plant on the west side of U.S. 85. A few de-watering projects in the Sterling and Fort Morgan areas have proved successful in alleviating high ground water there.

Drawbacks: Pipelines are expensive. If Gilcrest has to increase the size of its pipeline, which also carries sewage effluent and stormwater to the South Platte, it will cost millions. A prior de-watering well across U.S. 85 to the east of Gilcrest’s sewage treatment plant put water into the Big Bend Drain, which carried it to the Union Ditch. But Union Ditch officials don’t want de-watering water in the ditch during times of call on the river, as it could make the ditch company liable for any water lost en route to the river.

Drainage districts — The committee also recommended formalizing drainage districts. Like water conservancy districts, drainage districts are cooperative organizations that pool resources for a common cause. Prevalent in the past, drainage districts that performed regular maintenance on farm-related drainage facilities became defunct at some point. That’s one reason the Big Bend Drain near Gilcrest is in such bad shape, overgrown with weeds and in need of re-digging.

Pump instead — A two-year pilot project, from 2016-17, paid selected farmers $60 per acre foot to pump wells rather than use surface water for crop irrigation. Because farmers are given only a limited number of well pumping days, they often save those days until they absolutely need them. Electricity costs also dissuade farmers from pumping rather than using surface water.

Drawbacks: Without a continued incentive for well pumping, farmers are likely to prefer surface water irrigation. It’s cheaper and more plentiful.

More storage — Building more storage along the South Platte near Gilcrest would create more predictable augmentation supplies, meaning the Central Water Conservancy District could use those supplies for recharge projects that eventually allow more well pumping.

Drawbacks: Storage projects come with high price tags, and producers still may not pump their wells even with higher quotas.

Irrigation efficiency — Through cost sharing programs, the committee recommends farmers look into hardware that would increase irrigation efficiency, including sprinkler systems, drip systems, pond and/or on-farm ditch lining, soil probe installation, soil mapping and tile drain systems.

Drawbacks: The solutions can be expensive, particularly drip systems.