Vision, engineering turn pits into paradise

WINDSOR – Don Taranto, president of TST Inc. Consulting Engineers, knows it might be difficult for people to visualize what the Water Valley development in Windsor looked like as a gravel quarry.

“When it was in process, it looked like a war zone,” he said. “Those people who bought homes there before the mining phase was complete took a risk. Now the assessed value of homes in Water Valley is significantly higher than what we predicted.”

No wonder. Water Valley, still a work in progress as the 652 acres of Water Valley South take shape, looks as if it had been lifted from somewhere near a seashore and deposited on the high desert of Northern Colorado. The 18-hole golf course along the Poudre River is complete; a nine-hole complement with its own waterfall is on the way. One would be hard pressed to find a trace of the mining operation that recently dominated the landscape.

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“The original plan was to lease the mineral rights,´ said Martin Lind, owner and developer of Water Valley. “Actually, we were willing to give the rights away, but when we couldn’t find a company that would do it the way we wanted it, we decided to do it ourselves. For about four years we were the largest aggregate producer in the area.”

As the mining operation proceeded, Lind embraced the current trend for planning restoration from the outset of a project and coordinating restoration with quarrying activities.

“We configured the lakes to suit the development needs,” Taranto said. “TST did all the grading plans and all the infrastructure.”

The plan called for taking the pits down 18 to 22 feet, where gravel turned to clay. Then by digging a little deeper, the clay under the gravel became the material for lining the lake.

“We created clay liners and left the lakes dry so that they could be inspected,” Lind said. “Then we took our historical water rights and filled them up.”

Creating clay liners for the lakes suited the plan to sculpt the pits rather than just dig out the gravel. Taranto pointed out, however, that there is another commonly used method for reconfiguring a pit’s position in the hydrologic equation. A trench dug around the mining operation down to bedrock surrounded by a slurry wall turns a pit into a water container.

“This technology was developed so that mining companies could ‘dewater’ the deposit area,” he said. “Now it’s also used as a way to preserve water resources.”

Impact on neighbors

It turns out that the risky, multi-layered approach to Water Valley’s development has had many benefits: aggregate for the golf course, sand for the lakeshores and peace with the soon-to-arrive neighbors. Indeed, neighbors can be a major headache in the process of developing new mining operations for aggregate, a natural resource that can easily vanish under a parking lot or subdivision. Lafarge, the biggest company for building materials in the world, has to build relationships with stakeholders before it can dig.

“We have to be sensitive to the communities we are working in,´ said Gary Pearcy, local aggregate sales manager for Lafarge. “No one wants a scarred-up landscape close to their property.”

Understandably, residents in established neighborhoods are not keen on having nearby open land turned into open pits with the noise that goes with the heavy digging. Thus, the negotiations between a mining company and neighborhoods can be drawn out and sometimes acrimonious – such as the fight over a proposed pit between North Taft Hill Road and Overland Trail. In that case, he owners of the parcels were happy to lease their land. Surrounding neighbors were less enamored of the idea, despite the Lafarge reclamation plan that called for the creation of five ponds.

“If construction continues at the rate it’s going in Colorado, that site will be mined out before 10 years,´ said Taranto, who is familiar with the Taft Hill site. “Ponds like those that are part of the Lafarge reclamation can be a huge amenity and recreational asset. You can use them for fishing and, if they are big enough, water sports.”

It seems likely that the “Overland Ponds” will fill up earlier rather than later. According to the Lafarge North America Web site, the demand for aggregate in Colorado exceeds 12 tons per person per year.

How much water?

While the guidelines for reclaiming mined property are clear and the reclaimed pits have to be certified by the state, not all reclamation efforts are created equal.

“There are lots of ways to mess it up,” Taranto said. “You can scrimp on materials and ignore the aesthetics of the edges of a lake. Without grass or sand, the edges end up as mud pits.”

More significant than the look of the edges is having a plan to make sure that the lakes will stay full in both wet and dry years.

“How much water is enough?” Taranto asked. “You have to have an engineering plan for the lakes that takes water rights into account. It’s easy to keep a lake full in a wet year. In a dry year you have to be sure your water rights will keep it full.”

Lind’s love of water and long history in farming in Northern Colorado had taught him the intricacies of the ditch system and water rights.

“Our historical water rights will keep the lakes full,” he said. “In the summer we have boat races.”

Properly engineered, lakes reclaimed from mining operations keep their water from commingling with ground or nearby river water. As a result, while the use of the land may have changed from farmland to mining land to residential land, the effects on the way water moves and evaporates are kept to a minimum.

In Taranto’s view, the Water Valley project has not only reset the bar for reclamation, it has redefined expectations. Lind’s development cleaned up a stretch of the Poudre River that was polluted, transformed a piece of land that had been a dumping ground for sugar-beet waste and created sandy beached lakes big enough for a refurbished Louisiana paddle boat to cruise on.

“Martin invested in amenities early in the process,” he said. “It was risky because there was no quick turnaround on the investment. The next developer who tries something like this will face less risk, but much higher expectations.”