Since 2017, the city of Aspen’s water use has remained steady, illustrating the difficulty of reducing consumption through voluntary conservation measures amid continued growth and the effects of climate change.
According to numbers provided by city staff, total metered accounts for water use between 2017 and 2021 hovered between 800 million and 900 million gallons per year coming from the city’s treated-water system. Aspen’s system serves about 3,960 customer connections in the city’s urban-growth boundary.
2019 — a wet year — saw the lowest use in the data set, down to 828,650,350 gallons, or about 2,543 acre-feet. (An acre-foot is the amount of water needed to cover an acre of land to a depth of 1 foot and can typically meet the annual needs of one or two families.)
Despite the COVID-19 pandemic, which closed or limited many businesses, stores, restaurants and government facilities, the year 2020 saw water use rise 7.7% from 2019 to about 2,739 acre-feet. Water use then dropped 4.7% in 2021 to about 2,612 acre-feet.
Water use is very seasonal in Aspen as outdoor watering represents about 70% of the city’s total annual water use, according to Tyler Christoff, the city’s director of utilities.
In July and August 2021, residential use was seven times as much as in the offseason month of April. And residential use in the summer months was five times greater than that in January.
2022’s June-September irrigation season recorded the second-lowest total water use since 2017, with about 1,546 acre-feet, after 2019’s 1,523 acre-feet. Summer residential use dropped by 3.3% from last year.
Each year, about half of Aspen’s treated-water use is residential, which includes both indoor water use and outdoor lawn and landscaping watering, and one-fourth of the total water consumption is commercial. Multifamily units, irrigation and city facilities account for the rest.
Aspen’s water use also tracks closely with local drought conditions, with drier years seeing more water use. For example, water use was down in 2019, when Pitkin County did not experience drought conditions during the irrigation season until September, according to the U.S. Drought Monitor. Water use was up the following year, when Pitkin County experienced increasingly severe drought conditions as the summer went on, reaching extreme drought by mid-August. With more rain over the past two summers, water use was lower than in 2020.
The past several years of steady water use have shown that despite a much-praised water-efficient landscape ordinance designed to limit water use in redevelopment, smart meters, a tiered rate system that charges big water users more and year-round Stage 2 water restrictions, getting some customers to change their behavior, especially when it comes to outdoor watering, is challenging.
“I think (outdoor use) is not as well understood from a conservation perspective,” Christoff said. “It’s not a water use that you are directly interacting with on a daily basis. Most irrigation is automated. It just kind of occurs, and that creates an inherent kind of disconnection.”
But Christoff said the fact that Aspen’s water use has remained mostly flat while the number of taps and fixtures has increased is a win. According to numbers in Aspen’s 2015 Water Efficiency Plan and numbers provided by Christoff, Aspen’s equivalent capacity units (ECUs) have gone from 17,300 in 2014 to 17,853 in 2021, about a 3.2% increase, creating more demand on the system. One ECU is equivalent to a one-bedroom, one-bathroom home with a fully equipped kitchen.
“I really think it’s a positive thing that we have stayed relatively steady despite more fixtures, more use, more visitation, more building, all of those things,” Christoff said. “That’s really a credit to our conservation program and our community understanding that the resource is finite and wise use of it is really important.”
Aspen aims to use enhanced conservation to address some of its projected water shortages in the future. According to Aspen’s Integrated Water Resource Plan, enhanced conservation could be used to decrease indoor water use by 12% and outdoor use by 25% by the end of 2070. But it also said the yield from enhanced conservation is uncertain because it depends on customers’ behavioral changes. Hotter temperatures from climate change are also predicted to increase outdoor watering demand.
Aspen’s IWRP, which was completed last November by consultant Carollo Engineers, lays out Aspen’s projected water shortages for 50 years under future climate change and growth scenarios. Under the worst-case scenario — where climate change increased outdoor watering by 25% and a 1.8% growth rate that pushed Aspen’s total population (including seasonal residents) to almost 68,000 people, with only modest conservation — Aspen’s total water demand could be 9,281 acre-feet by 2070. The worst shortfalls under those conditions could occur in two consecutive dry years and be about 2,300 acre-feet total over the course of both years, according to the IWRP. The report offers six portfolios of water-source combinations to make up the shortfall, including a potential 5,820-acre-foot reservoir that was estimated to cost $400 million in 2021 dollars.
Christoff said that although the 25% figure is aggressive, he believes it’s attainable and pointed to the city’s water-efficient landscaping ordinance as one path to getting there. Aspen’s landscaping standards, enacted in 2017, set an upper limit for water use for any project — including landscaping, grading and construction — that disturbs 1,000 square feet and more than 25% of a property. (The ordinance is also triggered by a redevelopment of 50% or more of an existing structure.) That limit is set at no more than 7.5 gallons per square foot per season. Redevelopment and new development must meet certain criteria for soil, plant material and irrigation systems, and must submit a report from a third-party certified landscape-irrigation auditor.
Christoff said there have been 87 projects permitted so far under the water-efficient landscape ordinance. The city’s goal is to save 37 acre-feet each year with the ordinance by 2050. Christoff said of the 87 projects permitted, only about 10 are complete and have passed final inspection, so he could not put a number on how much water had been saved so far.
“We still need a few more years of projects working through the process to start being able to really quantify these savings,” he said in an email.
Aspen’s 2015 Water Efficiency Plan had a goal of reducing demand in 2035 by almost 600 acre-feet per year relative to what demands were projected to be without implementation of the water-efficiency program. Christoff said city staff feels like they are on track to meet this conservation goal.
“Our Water Efficiency Plan provides an outline and roadmap for these efforts,” he said in an email. “If we are able to successfully follow our plan and continue to see community support, we believe we will hit our targets.”
Some Western Slope cities have focused in recent years on getting a handle on outdoor watering because it is what is known as “consumptive” use. For residents on a municipal water system, with indoor water use such as showering, washing dishes and flushing toilets, the water goes down the drain and to the wastewater-treatment plant, where it’s cleaned and released back to the river. The vast majority of indoor water use is “non-consumptive.”
But with outdoor watering, lawns, shrubs, trees and soil absorb most of the water; it depletes the waterway from which it comes.
Since 2012, the Eagle River Water & Sanitation District, which provides water to the Vail area, has focused its conservation efforts solely on outdoor use.
“We don’t need to worry about indoor water; it goes back to the river,” said Diane Johnson, communications and public affairs manager for the district. “We just need to concentrate on outdoor water use, so that’s what we’ve done. Lawn watering is our first target.”
As climate change increases temperatures and lengthens the growing season, some of the water savings through efficiency and conservation programs may be wiped out. Water use during drought years, such as 2020, remained stubbornly high in Aspen. And a review of Bureau of Reclamation data by Colorado River experts suggests that water use throughout the upper basin is greater in dry years and less in wet years. If the water isn’t falling from the sky, people tend to take more from the rivers.
Residences among largest water users
If Aspen wants to reduce overall water use, it will have to address the largest water users, including residences with lots of outdoor watering.
“Conservation from the highest water users could have the largest impact on overall water use reductions,” the IWRP reads.
According to the IWRP, two single-family residences were in the top 10 individual water users in 2018, alongside Aspen’s biggest hotels, apartment complexes and city facilities. The two residences — which the city does not identify — were the seventh- and eighth-biggest water users, using 6.5 million gallons (nearly 20 acre-feet) and 5.8 million gallons (nearly 18 acre-feet) of water, respectively. The seventh-biggest water user used 1.4 million gallons (about 4.3 acre-feet) per ECU.
According to the IWRP, much of this high water use may be attributed to outdoor use. About 70 of more than 2,500 single-family residential accounts show water use of more than 1 acre-foot per year per ECU.
Christoff said city staff reach out to these large users with the offer of a free irrigation audit to assess their water use. Smart metering that lets staff and residents check their water use in real time also helps people better understand where they may be wasting water or have a problem such as a leak. But reducing use among Aspen’s biggest users, especially single-family homes, has been challenging.
Since 2005, Aspen has had a four-tiered billing structure in which properties that use more water pay a higher rate. But this doesn’t result in a reduction in water use for some customers, particularly those wealthy Aspenites who can afford to pay more.
“There are customers within our service territory where a financial disincentive is not a disincentive to them,” Christoff said. “Some customers, regardless of how high that third and fourth tier rates are, they are still going to use that amount.”
This concept is known as price inelasticity, where demand stays the same, despite fluctuating prices, said Lindsay Rogers, a water policy analyst with Western Resource Advocates who has worked with the city of Aspen on water projects.
“Customers who receive a pricey water bill, it might not motivate them to reduce outdoor water demand,” Rogers said. “That’s a challenge because that’s one of the biggest tools that municipal utilities have to encourage water conservation.”
Participants in a working group who helped shape Aspen’s IWRP said the city may be leaning too much on pricing to drive water conservation and cautioned that it may have a disproportionate impact on lower-income residents, while not creating a sufficient disincentive for other residents to reduce water use. The same group also ranked outdoor watering of lawns and landscaping as among the lowest priorities during a drought.
Aspen’s municipal code allows for fines or a municipal summons for chronic water-wasters who violate water restrictions. Stage 2 water restrictions, which have been in effect since September 2020, include the following: an even/odd day outdoor watering schedule depending on address; no watering between 9 a.m. and 5 p.m. except from a handheld hose or drip irrigation system; no outdoor watering of sidewalks, driveways or patios; and other restrictions.
But, according to Christoff, city staffers have never issued a fine or summons, although they have contacted property owners by email or letter. Aspen prefers education over enforcement, Christoff said.
“We talk to a number of water providers around Colorado, and across the board for the most part, folks either don’t have the staff capacity or inclination to enforce it,” Rogers said. “A lot of people just don’t want to be water cops.”
Other cities have had success
Several municipalities in the Colorado River basin have been able in recent years to decouple water use from population growth. That means that water use decreases even as population increases. The Eagle River Water & Sanitation District and Upper Eagle Regional Water Authority have decreased overall water use by 6% while the number of single-family equivalent units increased by 25% since 2002.
Although water use has seen years of ups and downs, Aspen’s IWRP shows that since 1995, overall demand is generally increasing and is projected to continue increasing.
Some Front Range cities, which take a portion of the water from the Colorado River basin through transmountain diversions, have also seen some success with their conservation programs. Aurora, for example, has seen its population rise by 46% over the past two decades, but the amount of water it has distributed has decreased by 9%, according to numbers provided by the city.
But it hasn’t been easy, according to Aurora Water General Manager Marshall Brown. There is a limit to voluntary measures. Developers didn’t take advantage of a program that offered a credit for tap fees for water-efficient landscaping. And not many customers signed up for a $3,000 turf-replacement rebate.
“Going into this year, we said we’ve really got to ramp this up,” Brown said. “We’ve got to tie economics more directly to what we are doing is one of the lessons we learned. And we’ve got to come up with literally code restrictions because we couldn’t get much progress with voluntary stuff.”
Aurora was among a group of municipalities that signed a memorandum of understanding in August committing to reducing nonfunctional turf grass by 30%. Aurora City Council last month passed an ordinance that prohibits turf for aesthetic purposes in all new development and redevelopment, and in front yards. Turf in backyards is limited to 45% of the space or to 500 square feet, whichever is smaller.
“We know we will see results from that,” Brown said.
A draconian approach
Las Virgenes Municipal Water District provides water to several exclusive and gated enclaves of Southern California such as Calabasas and Hidden Hills. Like Aspen, the area is home to many wealthy residents who may not be as sensitive to water price hikes. The district made headlines this year when it began installing flow-restrictor devices on the homes of water wasters — those who used 150% or more of their monthly water budget four or more times.
The flow restrictors make it so that if more than one person in the home or more than one appliance is using water at the same time, it will come out as an annoying trickle. But the real goal of the restrictors is to stop the functioning of outdoor irrigation systems, which account for about 70% of residents’ water use, according Michael McNutt, the water district’s public affairs and communications manager.
“It’s a great way to get a wake-up call to those individuals who just consistently abuse how much water they use,” McNutt said. “People have got to get the message. We provide the water and we educate and we provide tools, and if they are not going to control how much water they use, we will do it for them until they get the point.”
Water managers say increasing conservation can be challenging, in part, because residents are resistant to change. Thirsty green lawns have been part of American culture and an aesthetically pleasing symbol of prosperity for a long time. But as climate change and drought continue to rob the West of water, that attitude needs to change, McNutt said.
“The barrier I’m seeing is evolving that mindset into something where I can have climate-appropriate landscaping throughout my property and I’m going to look at that and find that just as aesthetically beautiful as a green lawn,” he said. “Green lawns are going to be a thing of the past.”
Although Christoff said there is currently little appetite among Aspen’s elected officials for more-aggressive monitoring of residents’ water use, tools such as the flow restrictor could be part of the city’s future, especially as climate change pushes water utilities to do more with less.
“I think stuff like that is absolutely on the plate,” he said. “That’s not, as a water manager, where I’m looking to go, but as the resource becomes more in demand or more scarce, those drastic-type measures might come more to the forefront.”
Aspen Journalism is supported by the city of Aspen’s community nonprofit grants program.
Aspen Journalism covers water and rivers in collaboration with The Aspen Times. This story ran in the Nov. 24 edition of The Aspen Times.