The Broomcorn Express, Quarterly Publication of the Friends of Broomfield History
Vol. 4, No. 2, April–June 2024
“The past is never dead. It’s not even past.” William Faulkner1
OVERVIEW
If you find yourself driving along North Indiana Street near where it intersects with State Highway 128, looking to the southeast, you’ll see a large man-made lake known as the Great Western Reservoir3 in the foreground and the skyline of Denver in the distance. But unlike the nearby Standley Lake reservoir, there’s no regional park or general access road leading to the Great Western Reservoir,and understanding why requires a bit of digging into our local history.
BEGINNINGS
Adolph J. Zang created the Broomfield Reservoir and Ditch Company to fund the creation of the Great Western Reservoir for irrigation water for agricultural purposes. The Zang family had already built up a land holding of over one thousand acres. According to one reference, work on the reservoir began around 1903 and wasn’t completed until 1911, with water to fill it coming from Clear Creek and Coal Creek.
In the archives, we have a map of the original design for the reservoir, created by E.L. Rogers, the project’s engineer. The issue of Colorado water rights was just as important in 1903 as it is today, so part of the permitting process involved understanding where the water to fill the reservoir would come from. A.J. Zang made claim to water from the Big Dry Creek, which he would use to fill the Great Western Reservoir. The State Engineer, L.J. Garpeuter, stated that A.J. Zang’s claim (certificate below) was approved by the State of Colorado before construction started. A certificate from the Broomfield Reservoir and Ditch Company is below.4
Land and water rights allowed Zang to grow essential cash crops for beer production, such as wheat, oats, and barley, which added to the family’s wealth.
THE TURNPIKE LAND COMPANY ACQUIRES ZANG’S RANCH
In the 1950s, the Turnpike Land Company started to market Broomfield Heights as a planned subdivision. The Company itself was a privately held corporation that was run by handful of stockholders with a strong vision to transform farmland into a city. In 1955, they bought what had been the Zang’s Ranch. That acquisition allowed the Great Western Reservoir to become a reliable source of water for the expanding town, with the construction of a water main to a new treatment plant. The view was that the development now had “a reservoir big enough for a population of 30,500 for a year and a half if never a drop was added.”6 Having access to water was so important that tours were arranged for Denver-based relators, which included a stop at the reservoir.7
Starting in 1963, the Broomfield Heights Mutual Service Association was selling water from Great Western Reservoir to the city.8 By 1971, expanding Broomfield was getting its water supply from both the Great Western Reservoir and Denver Water.
redrawn from earlier Department of Energy Data
CONTAMINATION OF GREAT WESTERN RESERVOIR
Rocky Flats is immediately West of the Great Western Reservoir. From 1952 to 1989, Rocky Flats was home to a factory producing components for nuclear weapons. In 1970, the EPA tested water in Walnut Creek, which both feeds the reservoir and drains out from it, and detected plutonium in the water,contaminated by leakage from Rocky Flats. The EPA found 40 times normal levels of plutonium in the layers of mud at the bottom of the reservoir in 1973.9 With a half-life of 24,000 years, plutonium-239 is potentially cancer-inducing if inhaled in sufficient quantities, so contamination of the city’s primary water supply was understood to be a potentially serious public health hazard. The map above, redrawn from earlier Department of Energy Data,10 shows a plume of plutonium contamination originating at Rocky Flats.
Also, in 1973, radioactive tritium from contaminated scrap material at Rocky Flats was discovered in Walnut Creek and the Great Western Reservoir.11 In 1976, the task force report about the contamination issues originating at Rocky Flats included a statement that the plant’s continued operation was important to the local economy. However, a 1977 newspaper article describes the Broomfield City Council’s reaction to the task force’s report: “That was when we blew our stack,” said Goerge [sic] Di Ciero, Broomfield’s city manager. “They had mistakes, accidents and incidents up there and they were, in effect, telling us we should take it because of their payroll.“12
On June 6, 1989, the FBI and the EPA raided the Rocky Flats plant to collect data on potential violations of environmental law based on multiple serious incidents related to the release of radioactive plutonium and tritium, and agents stayed on site through June 26. Consequently, Broomfield immediately switched sourcing drinking water to Denver Water. Local citizens dug a ditch to divert water from Walnut Creek around Great Western Reservoir.13 Ultimately, a DOE grant and sale of Broomfield’s Clear Creek water rights funded the 1991 Great Western Reservoir Replacement Project to build a new Broomfield drinking water infrastructure, including water rights, a new water treatment facility, and a pipeline to bring water to the facility. The 1991 Replacement Project also expanded the secondary water supply through a contract with Denver Water. Interestingly, that agreement was opposed by local environmental groups fearing that water availability in Broomfield would accelerate a mass urbanization mess.14 By 2004, the Great Western Reservoir had been relegated to being a component of the water reuse system that provides non-potable water for irrigation purposes in Broomfield.
CURRENT EVENTS
The current state of Great Western Reservoir is a legacy of an earlier time in Broomfield that is associated with atomic weapons production. Clearly, a short trip to the west side of Broomfield provides a highly visible local artifact of history that is more powerful than just a stock certificate or an old picture. While researching this topic, I didn’t expect to find a Denver Post article dealing with local advocacy groups suing multiple federal agencies to halt work on a trail through the Rocky Flats National Wildlife Refuge—through what they still considered the most plutonium-contaminated part of the area.15 Before that, the Jefferson Parkway project was supposed to provide a segment of a beltway circling Denver—until Broomfield withdrew its support, at least in part because of concerns stemming from a high Plutonium sample reading in 2019 on the east side of the Rocky Flats reserve.16
On a more mundane level, the open space surrounding the Great Western Reservoir has been the subject of multiple news articles in recent years because of bubonic plague infections among the local prairie dog population.17 There is an obvious need to let people know about these outbreaks, which could spill over into surrounding areas; still, it is interesting to read about the plague closing this area of open space that is normally not open to the public.
BIGGER TRENDS
Great Western Reservoir can be seen as part of the wider Front Range story of needing to secure water rights and create a delivery infrastructure to support further development. Obviously, there was urgency and necessity to deliver the Great Western Reservoir Replacement project in 1991, but the timing was also good because at that point, there was less development in the region. Consider that Thornton has water rights from the Cache la Poudre River and cannot get approvals to build a pipeline to access that water from neighboring counties—another example of development occurring where there isn’t water, and creating jurisdictional clashes and elevating environmental concerns.18
We also know that the historic nuclear impact from Rocky Flats is not just a Broomfield concern, nor is it the only environmental concern in the region. There are concerns about the safety of the Candelas development in Arvada immediately to the south of what had been the Rocky Flats site.19 On December 27, 2023, homeowners filed a lawsuit about the noise and lead pollution originating from flight activities at the Rocky Mountain Regional Airport.20
Clearly, concerns about water access and environmental pollution are not confined to Broomfield’s local history and the past but continue to be current issues here and in surrounding areas.
SUMMARY
The history of the Great Western Reservoir in some ways reflects the history of Broomfield itself, moving from a sparsely populated agricultural area and transforming into a suburban community with new requirements and challenges, including the need to deal with the longer-term effects of surrounding developments. We also know that even after remediating once highly polluted areas and converting them to a wildlife refuge or open space, there is still ambiguity about safety and appropriate new uses for those areas.
Off in a far corner of the county and not easily accessible, this area doesn’t make the news very often. Most online references to Great Western Reservoir today come from people asking about fishing access.21 Nevertheless, the Great Western Reservoir is an important piece of our local history that more people should know about.
EPILOGUE
If the preceding historical overview has raised questions in your mind about the state of Rocky Flats-related pollution on the Broomfield environment today, The Colorado Department of Public Health and Environment has a document on Rocky Flats Myths and Misunderstandings that may be helpful and reassuring.22 There should be no new contamination due to the closure and clean-up of Rocky Flats, although plutonium does remain in Great Western Reservoir sediments.
End Notes
1. “Requiem for a Nun,” Wikipedia, Last modified January 22, 2024, https://en.wikipedia.org/wiki/Requiem_for_a_Nun.
2. Sierra Guardiola, “50 Quotes about Time Passing,” Southern Living, October 5, 2023, https://www.southernliving.com/culture/quotes-about-time-passing.
3. See image above from MAPS.APPLE.COM. “Map of Great Western Reservoir,” Accessed January 24, 2024, https://maps.apple.com/?ll=39.899295,-105.153834&q=Broomfield — Broomfield County&spn=0.015976,0.036364&t=h
4. “The Broomfield Reservoir and Ditch Company stock certificate for A.J. Zang,” Broomfield History Collections, March 25, 1921, https://hub.catalogit.app/9352/folder/entry/0ced3f60-473f-11ed-ab8a-bf49b1a63c01.
5. “Map of the Great Western Reservoir,” Broomfield History Collections, 1904, https://hub.catalogit.app/9352/folder/entry/1c09b440-1b6c-11ee-94f2-2d7caf581c4c.
6. Advertisement quote from The Broomfield Builder, a publication of the Turnpike Land Company, https://hub.catalogit.app/9352/folder/a5ef4790-48a1-11ed-9b74-fb65c00c73a7/entry/272d1b10-48a3-11ed-ab8a-bf49b1a63c01.
7. “Great Western Reservoir,” c. 1956, Broomfield History Collections, https://hub.catalogit.app/9352/folder/entry/26dd7470-48a3-11ed-ab8a-bf49b1a63c01.
8. “Broomfield Water Resources,” Broomfield.org, August 2011, https://www.broomfield.org/DocumentCenter/View/7968/Water-resources-update-2011.
9. Bill Richards, “Plutonium Taints Their Reservoir.” Washington Post, March 21, 1977, https://www.washingtonpost.com/archive/politics/1977/03/21/plutonium-taints-their-reservoir/df5da12e-06b0-4171-883c-bba20f14f46d/.
10. Jessica Peakes, submitted as a final project for GEOG 3053, University of Colorado, Boulder, “A Geographical Study of Rocky Flats and Surrounding Areas,” ArcGIS StoryMaps, December 11, 2021, https://storymaps.arcgis.com/stories/773c125c28454013972812b65454a7c2.
11. Patricia Buffer, “Rocky Flats History,” Energy.gov, July 2003, https://www.energy.gov/lm/articles/rocky-flats-site-colorado-history-documents.
12. Richards, “Plutonium Taints Their Reservoir.”
13. Silvia Pettem, Broomfield: Changes through Time, paperback, 1st ed. (Book Lode, 2001),190.
14. Pettem, Broomfield: Changes through Time, 87.
15. Katie Langford. “Colorado Environmental Groups File Federal Lawsuit to Halt Rocky Flats Trail.” The Denver Post, January 8, 2024, https://www.denverpost.com/2024/01/08/rocky-flats-lawsuit-colorado-physicians-social-responsibility-plutonium/.
16. John Aguilar, “Arvada, Jefferson County Sue Broomfield over Beleaguered Jefferson Parkway Project,” The Denver Post, June 6, 2022, https://www.denverpost.com/2022/06/06/jefferson-parkway-lawsuit-arvada-jefferson-county-broomfield/.
17. Breanna Sneeringer, “Plague Closes Open Space until Further Notice in Colorado,” OutThere Colorado, July 13, 2020, https://denvergazette.com/outtherecolorado/news/plague-closes-open-space-until-further-notice-in-colorado/article_aad4b47b-9657-5ecc-b3d6-fa78e7c58051.html.
18. Michael Booth. “Thornton Has Plenty of Water — It’s Just in the Wrong Place. And That’s a Very Colorado Story,” The Colorado Sun, September 6, 2023, https://coloradosun.com/2022/12/04/thornton-water-rights-pipeline-larimer-county/.
19. Heidi Beedle, “The Nuclear Legacy of Rocky Flats: Health, Contamination Concerns Linger,” Colorado Times Recorder, April 24, 2023, https://coloradotimesrecorder.com/2023/04/the-nuclear-legacy-of-rocky-flats-health-contamination-concerns-linger/53105/.
20. Rob Harris, “Hundreds of Homeowners Sue Rocky Mountain Metropolitan Airport Alleging Harm to Property Values.” Denver 7 Colorado News (KMGH), December 28, 2023, https://www.denver7.com/news/local-news/hundreds-of-homeowners-sue-rocky-mountain-metropolitan-airport-alleging-harm-to-property-values#:~:text=BROOMFIELD,%20Colo.,have%20hurt%20their%20property%20values.
21. On the internet you can find pictures of people who say they have caught fish in The Great Western Reservoir. If this is accurate, the activity seems problematic on several levels. For an example see Fishbrain: “Fishing Reports, Best Baits and Forecast for Fishing in Great Western Reservoir,” https://fishbrain.com/fishing-waters/_8f-2t8I/great-western-reservoir.
22. “Myths and Misunderstandings [about Rocky Flats]” Colorado Department of Health and Environment, March 18, 2019, https://cdphe.colorado.gov/hm/rocky-flats-faq > Myths and misunderstandings (FAQ item).
Featured image: Apple Maps image of Great Western Reservoir