Here’s a look at exchanges on the Arkansas River, from Chris Woodka writing for The Pueblo Chieftain. Click through and read the whole article. Here are a few excertps:

So far this year, two Water Court filings involving yet more exchanges on the Arkansas River have been filed. Woodmoor Hills has filed for an exchange as a way to move water it intends to buy on the High Line and Holbrook Canals to Northern El Paso County. The Arkansas Valley Super Ditch, a group of shareholders from seven canal companies, has filed for an exchange that would allow them to sell water through leases with upstream users, such as Aurora, Colorado Springs and the Pikes Peak Regional Water Authority — the only user which has already signed an agreement with the Super Ditch.

Water trades, sometimes in the form of what are called contract exchanges, are not monitored by the state as part of river administration, Witte added. “Contract exchanges are not addressed in law, and not something we regulate,” Witte said. “It’s a contractual arrangement to help them move water where they need it.” The trade of 5,000 acre-feet between Aurora and the Pueblo water board is an example of that type of arrangement, Witte said.

Plans for augmentation, primarily used now to make up depletions from well pumping, are not exchanges, but require adjudication in Water Court, Witte said. Like an exchange, augmentation plans allow for out-of-priority diversions to make up for depletions. “The party making the transaction is only replacing their depletions,” Witte said. “The big difference is that if it were an exchange, they would need to tell the world and convince them (the engineering) is true.”

Other similar ways to move water may be alternate points of diversion or changed points of diversion. These occur by moving the diversion of a water right upstream. Water can then be left in storage for use at a later date. Winter water storage is an example of how an alternate point of diversion is used.

Substitute supply plans, such as one being used by Manitou Springs that allows it to store water by replacing it from a new source, is probably not an exchange, Witte said. “It’s not really an exchange, but a water management practice that causes no injury,” Witte said.

More on Arkansas River exchanges from Chris Woodka writing for The Pueblo Chieftain. From the article:

By far, the top driver on this peculiar road is Colorado Springs, which operates an exchange by storing water out of priority in Lake Pueblo against its sewer return flows down Fountain Creek. It’s a complex accounting system that incorporates a lot of moving parts, including the transit loss along Fountain Creek, agreements with other water users and determining the nature of water being used. Each year, Colorado Springs submits an accounting to the state explaining how all the variables were factored in.

Fully consumable water can be used to extinction under state law, whether it’s imported or simply the consumptive use of water rights formerly used for agriculture that have been moved for use in a municipal supply. About 85 percent of Colorado Springs’ water supply falls into those categories, and much of it is now being reused through the Fountain Creek exchange. In recent years, the range has fallen between 20,000 and 25,000 acre-feet annually, but the amount of exchanges could double when the Southern Delivery System is fully operational. Last year was no exception, as Colorado Springs moved a little more than 20,500 acre-feet of water via its Fountain Creek exchange, according to Division of Water Resources figures made available to The Pueblo Chieftain…

In all, about 83,000 acre-feet of water that once would have flowed down the river was stored in Lake Pueblo last year, most of it through alternate points of diversion, rather than exchanges. That amounts to nearly 12 percent of the river’s annual flow at Avondale. More than half of that — 46,361 acre-feet — was stored during the winter water program, a court decree that allows flows to be captured rather than used for irrigation. Water also was stored at downstream reservoirs like John Martin and Meredith as part of the program. Aurora stored about 11,500 acre-feet, mostly using alternate points of diversion decreed by courts in its two cases involving purchases of water rights on the Rocky Ford Ditch. Aurora also could move water from the rights it purchased on the Colorado Canal in Crowley County through exchange…

Pueblo, which has the highest exchange priority on the Arkansas River under a 1987 court settlement among water users in nine court cases, exchanged very little water last year. “We didn’t use much of our transmountain water, so there weren’t return flows to recapture,” explained Alan Ward, water resources administrator.

More Arkansas River Basin coverage here.