Windy Communication Gap
Longmont’s noisy and, well, windy dispute over Water Storage Bond — Ballot Issue 2J pits the environmentalists of Longmont against the unabashedly pro-growth faction. Green against green. Planet against Profit. The environmentalists want to divert from the Colorado River only the minimum that Longmont needs to survive. Or nothing at all. The Boosters want to grab all the water we can get, “just in case.” And the consequences of not doing what the city recommends (despite there being conflicting recommendations) are purported to be dire indeed.
In all the furor, some important ideas have been lost. Folks on both sides talk about this as though it’s about diverting water from the Colorado, and as if the Firming Project guarantees a certain level of water supply to Longmont. Neither of those things are true.
That’s why The Weathervane has published a story on Water Law [Wet Slope, Dry Slope] in addition to this discussion of the Windy Gap diversion and firming project in particular. We suggest you read “Wet Slope, Dry Slope” first before continuing with this opinion.
The Windy Gap Project
Windy Gap is a project conceived by Northern Water, a government agency created in 1937 for the purpose of gathering water from the Western Slope for the use of Northeastern Colorado. The Windy Gap Project is complete. It diverts, or purports to divert, water from the Colorado River and pumps it into Lake Granby. From there, the water moves through the existing Big Thompson distribution system, through the Alva B. Adams tunnel to Carter Lake, where it enters a system of pipelines that distributes it to the subscribers to the Windy Gap project. Longmont already receives some water from the Windy Gap diversion. It owns a theoretical right to well over 12,000 acre-feet of the water.
Uncertainty and Firming
The Windy Gap diversion is not an absolute right. It is designed to deliver an average of 48,000 acre-feet of water to the Front Range. It may, at need, deliver up to 90,000 acre-feet in a single year, but no 10-year running average may exceed 65,000 acre-feet per year. If that sounds complicated, just wait.
There are physical limitations, too. At very wet times, Lake Granby may already be too full to accommodate the full amount of Windy Gap water, and at very dry times the Colorado may not support the diversion. Both of those conditions cause the diversion to be curtailed, allowing the water to remain in the Colorado. The proposed Windy Gap Firming Project adds a new reservoir on the East Slope to act as a buffer to compensate for other fluctuations in the diversion system’s capacity. This deficiency is admitted to be an engineering error, if you dig hard enough into the Windy Gap history. It was clear all along that no water could be diverted in dry years. But nobody anticipated that in very wet years the diversion system wouldn’t function properly, either.
That “request” by the Project Participants became the Windy Gap Firming Project, which has been under study and planning for years. A location for the reservoir has been identified at Chimney Hollow, a valley just west of Carter Lake near Loveland. The proposed Chimney Hollow Reservoir would hold a maximum of 90,000 acre-feet of water. Theoretically, Chimney Hollow can be opportunistically filled using water already stored in Lake Granby from the original Windy Gap rights decrees, dating back to 1967.
There is no doubt that adding a reservoir at Chimney Hollow adds to the engineering soundness of the Windy Gap system, increasing the supposed “reliable supply” from Windy Gap from 0 acre-feet in a worst-case scenario to a best-case scenario of 30,000 acre-feet per year. But that 30,000 acre-feet is not, as it has been represented, a firm guarantee. And, even the best-case scenario is not as much water as the total combined water rights of the subscribers. Some of Longmont’s City Council candidates, in particular, speak as if there’s a constant supply of 10,000 acre-feet of water every year just waiting for Longmont to provide the bucket. Nothing could be further from the truth.
What is the Question?
Ballot Issue 2J asks the voters to approve a bond issue to partially fund the construction of the Chimney Hollow Reservoir. Longmont’s share will create storage space for 10,000 acre-feet of water, and the storage space is what the city will own. This has nothing whatsoever to do with the actual water right.
Well, actually it has one thing to do with the right. The original decree assumed that the water would be stored on the Western Slope, in tiny Windy Gap Reservoir and Lake Granby. If the voters approve the bond issue, then Longmont must go to Water Court for a ruling as to whether a right to store the water on the Eastern Slope exists at all. An unfavorable ruling would prevent the bond issue.
The city council debated other funding levels from 6,000 ac-ft to 12,000 ac-ft. per year. The debate stems from the fact that the city water engineers recommended that Longmont will only need 6,000 ac-ft more at build-out, while proponents of maximum economic growth argued for funding the maximum of 12,000. A compromise was reached, and the ballot issue proposes funding for 10,000 acre-feet per year.
The public documents and discussion on the Windy Gap Firming Project leave a number of questions unanswered. Here are some of them.
- What are the consequences to the Reservoir plan if Longmont does not fund 10,000 acre-feet? Will Chimney Hollow actually be built to lower capacity?
- What happens to Longmont’s water rights above the subscription amount? In the original project, Longmont had rights to over 12,000 acre-feet.
- How certain is the promised “reliable supply” if the Chimney Hollow Reservoir is built?
- What are the consequences to the Colorado River ecosystem of the Windy Gap diversion and firming?
What are the answers?
A1: What are the consequences of firming less than $10,000 ac-ft?
According to the city website, what Longmont gets is 1/9 of the stored water, and what it’s paying for is that share of the reservoir’s construction costs. How much capacity Longmont buys does not affect Longmont’s water right in any way. The city anticipates than another subscriber, such as Loveland, would subscribe for the capacity that Longmont leaves on the table, so that the project would continue to be funded. If no subscriber did that, then the project would presumably be under-funded, and an engineering replan would be required.
An important consequence to Longmont is that it would not need a bond issue. It could still subscribe to firm 6,000 acre-feet with saved money already put aside for this purpose. That’s exactly the amount of stored water the city staff predicts will be needed over and above existing supplies, when Longmont has reached its maximum growth. Some residents of Longmont are becoming concerned by the amount of debt the city has taken on, and what percentage of their taxes and utility rates goes to paying interest on bonds.
A2: What happens to Longmont’s water rights?
Again, longmont’s water right is unaffected by the Firming Project. If Longmont subscribes to the Firming Project for 6,000 acre-feet, it loses only water storage capacity for the remaining water. And if Longmont pulled out of the Firming Project altogether, it would have the same level of uncertain access to water from the Windy Gap Diversion as it does today.
Colorado law is very specific in defining when a water right owner has abandoned a water right, and under what circumstances failure to use the water does not constitute abandonment. Participation in a conservation program is one of the circumstances wherein an owner may fail to use water and preserve a claim. This aspect of the issue has not entered the public discussion at all. However, the City Staff and the City Council know this perfectly well, and in fact the Windy Gap water that cannot be stored at present is being used in sensible ways that qualify as the sort of “beneficial use” that preserve Longmont’s claim. The environmentalists’ view is that the most beneficial use of the water is leaving it in the Colorado River, and their demand that Longmont do this is perfectly doable.
A3. How certain is the “reliable supply” that Chimney Hollow provides?
Refer to our companion article, “Wet Slope, Dry Slope.” A Compact call from the lower Colorado Basin would shut off the Windy Gap diversion, which is the junior-most of all the trans-basin diversions on the Colorado River. Longmont has many other sources of clean water, such as the Ralph Price Reservoir, and does not need the Windy Gap water today at all. But if Longmont bases its growth on having that “reliable supply,” it could get into a shortage situation in a long drought.
It should be noted that Longmont, in its water needs analysis, placed the probability of a Compact Call interfering with the Windy Gap diversion at 0. WTF found at least one source that places that probability at 50–50 if, in future, the water volumes in the Colorado basin decline by only 20%. Further, the Windy Gap water right is so junior that many circumstances less dramatic than a full Compact Call still curtail the diversion.
A4. What are the consequences to the Colorado River ecosystem of the Windy Gap Diversion?
There is a fish and wildlife mitigation plan associated with the Windy Gap Firming project. It allows for curtailment of the diversion to ensure that the water temperature in the Colorado River remains cool enough for the fish population, and to let excessive sediment be flushed from the river basin. This is not as important without the Firming Project, because in wet years the large amount of flow down the Colorado fulfills the needed cooling and flushing functions anyway. In dry years, there is no water available for this purpose no matter what.
However, as the diagram at left reveals, the Windy Gap diversion reduces the Colorado basin to less than 30% of its historic flow. And with the Firming Project, which allows the diversion to operate more consistently, combined with an expansion of the Moffat Tunnel diversion planned during the same time period, the Colorado will retain less than 20% of its original flow.
Not the Answer (WTF are we doing here?)
It would be folly to base plans for future growth in Longmont’s population, mixed-use or industrial base, on this house of cards. The project was flawed to begin with, and the Firming Project is just a patch. It is hard to imagine an ethical frame that condones this destruction of the entity that carved the Grand Canyon.
We have seen that Denver Water successfully reduced domestic water consumption by 20% over a 15-year period. Denver still has green lawns, though it also offers strong incentives to xeriscape. Longmont could do the same. In fact, its water use has been nearly stable since 2014, a period that did see population growth.
The subscribers to the Windy Gap Firming Project are Platte River Power Authority, Broomfield, Erie, Greeley, Longmont, Louisville, Loveland, Superior, Central Weld County Water District, Evans, Little Thompson Water District, Lafayette, and Fort Lupton. The project may have too much momentum to reverse.
Still, it should be stopped. Finding a way to put Longmont’s 12,000 acre-feet, or even the 6,000 acre-feet of that right that the existing projections say we don’t need, back into the basin would greatly improve the river’s chances of surviving the drought that most climate change models predict. Conservation, and commitment to controlled, responsible growth and zero waste are the way forward for Longmont. In the twenty-first century, the kind of excess the Windy Gap project represents is a crime against the Earth.
WTF Colorado urges Longmont residents to vote NO on Ballot Issue 2J.
References
The Citizen’s Guide to Colorado’s Transbasin Diversions
Personhood for the Colorado River
