Water Security & Conservation

The Problem

Denver sits in a semi-arid climate that receives approximately 14-17 inches of precipitation per year - less than half the national average. The city depends overwhelmingly on mountain snowpack for its water supply: snowmelt collected in reservoirs along the South Platte River watershed and diverted from the Colorado River basin through tunnels under the Continental Divide. Both sources are under severe and worsening stress.

The Snowpack Crisis

Colorado’s snowpack - the frozen reservoir that feeds Denver’s rivers and reservoirs - is declining. The Colorado River basin has experienced a 20+ year megadrought, the worst in 1,200 years (Williams et al., Science, 2022). Warmer temperatures cause earlier snowmelt, reducing the amount of water that makes it into reservoirs during peak demand months. The U.S. Bureau of Reclamation has declared unprecedented shortage conditions on the Colorado River, triggering mandatory cutbacks for downstream states. While Denver’s direct Colorado River diversions (through the Roberts Tunnel and Moffat Collection System) have senior water rights, the broader basin crisis threatens the entire system’s stability.

Denver Water: An Island Unto Itself

Denver Water is an independent public utility - not a city department. It operates under its own board of commissioners, sets its own rates, and makes its own infrastructure decisions. The city government has limited direct authority over Denver Water’s policies. This governance structure means that Denver’s elected officials and residents have less control over one of the city’s most critical resources than they do over nearly any other public service.

Denver Water serves approximately 1.5 million people in Denver and surrounding suburbs. The utility has invested in supply diversification (the Gross Reservoir expansion, recycled water for irrigation) but has not adopted the aggressive conservation mandates that other western cities have implemented.

Water Use and Waste

Denver’s per-capita water use remains higher than many comparable western cities. Outdoor irrigation - primarily lawn watering - accounts for approximately 50% of residential water use during summer months. Denver Water has voluntary conservation programs and tiered water rates, but has not implemented mandatory outdoor watering restrictions outside of drought emergencies. Much of Denver’s urban landscape was designed for a climate that doesn’t exist here: Kentucky bluegrass lawns, water-intensive landscaping, and development patterns that ignore the semi-arid reality.

Water Equity

Water rate increases hit low-income families hardest. When water gets scarce, conservation mandates and rate structures that don’t account for income force working families to choose between water bills and other necessities. Large commercial users and wealthy homeowners with expansive landscaping consume disproportionate amounts of water. During the 2002 drought, outdoor watering restrictions were enforced in working-class neighborhoods while mansions in Cherry Hills continued irrigating acres of lawn.

What Denver Currently Does

Denver Water has implemented tiered water rates (higher per-gallon cost at higher usage levels), offers rebates for water-efficient fixtures and xeriscaping, and operates a recycled water system for irrigation of parks, golf courses, and some commercial properties. The Gross Reservoir expansion project (adding 72,000 acre-feet of storage capacity) is under construction and will improve supply reliability. Denver Water’s “From Forests to Faucets” program invests in watershed health. The utility’s long-range plan targets a reduction in demand through efficiency, but relies heavily on voluntary compliance and does not include mandatory conservation standards for new development beyond basic building code requirements.

Our Solution

1. Mandatory Water Conservation Standards

• New construction: All new residential and commercial development must meet water-efficient design standards - low-flow fixtures, greywater-ready plumbing, rainwater collection systems, and drought-tolerant landscaping. No new Kentucky bluegrass lawns in developments
• Existing buildings: Retrofit incentive program for water-efficient fixtures, with free upgrades for low-income households
• Outdoor irrigation: Year-round outdoor watering schedule (no midday watering, designated days by address). During drought conditions, mandatory reductions enforced equitably - large users cut first, not across-the-board restrictions that hit small households and large estates equally
• Commercial and institutional: Large water users (hotels, hospitals, universities, commercial laundries) required to submit water efficiency plans and meet reduction targets
• Golf courses and large landscapes: Mandatory conversion to recycled water or drought-tolerant landscaping on a 5-year timeline

2. Greywater Recycling and Water Reuse

• Citywide greywater framework: Adopt clear regulations enabling residential and commercial greywater reuse (shower, sink, and laundry water) for irrigation and toilet flushing. Colorado’s current greywater regulations are among the most restrictive in the West - Denver should advocate for state reform and lead with a municipal pilot
• Recycled water expansion: Extend Denver Water’s recycled water system beyond parks and golf courses to commercial districts, industrial users, and new residential developments
• Rainwater harvesting: Expand Colorado’s rainwater collection allowance (currently limited to two 55-gallon barrels per household) through state legislative advocacy. Incentivize collection systems for new construction
• Direct potable reuse: Begin planning for direct potable reuse infrastructure (treating wastewater to drinking water standards), following the lead of cities like El Paso, Singapore, and Windhoek, Namibia. This is the long-term future of water supply in arid cities

3. Drought Resilience Infrastructure

• Aquifer storage and recovery: Invest in underground water banking - storing excess water during wet years in underground aquifers for extraction during drought. Denver’s alluvial aquifers along the South Platte have significant storage potential
• Watershed protection: Expand investment in forest health and wildfire prevention in Denver’s mountain watersheds. Burned watersheds produce contaminated runoff and reduced water yield for decades. This is water infrastructure, not just environmental policy
• Stormwater capture: Convert stormwater from a flood hazard to a water resource. Green infrastructure (bioswales, permeable pavement, detention basins) captures stormwater for groundwater recharge rather than routing it to the Platte as waste
• Supply diversification: Support Denver Water’s efforts to diversify supply sources while demanding transparency and public input on major infrastructure decisions

4. Water Equity

• Lifeline rate: Guarantee affordable water for basic household needs. The first 3,000 gallons per month per household at a reduced rate, funded by higher rates on luxury consumption (pools, large-lot irrigation, commercial decorative water features)
• Tiered rate reform: Steepen the progressive tiers - make the first tier affordable, make excessive use expensive. A household using 5,000 gallons/month and a mansion using 50,000 gallons/month should not be on the same rate curve
• Low-income assistance: Expand Denver Water’s customer assistance program. No household should face water shutoff. Water is a human right, not a commodity
• Enforcement equity: During drought restrictions, enforce based on total consumption, not visible use. A working-class family with a small lawn patch shouldn’t face fines while a Hilltop estate irrigates through a drip system that’s technically compliant
• Renter protections: Ensure renters benefit from conservation rebates and fixture upgrades, not just property owners. Landlords who refuse efficiency upgrades face higher water rates passed through to them, not tenants

5. Democratic Governance of Denver Water

• Elected board: Transition Denver Water’s Board of Commissioners from mayoral appointment to direct public election, giving residents democratic control over their water utility
• Public rate hearings: Mandate public hearings with meaningful community input before any rate increase, with equity impact analysis required
• Transparency: All Denver Water planning documents, supply forecasts, and infrastructure decisions published in accessible, plain-language format
• Climate scenario planning: Require Denver Water to publish annual supply forecasts under multiple climate scenarios (moderate warming, severe warming, megadrought continuation) so residents understand the real risks
• Regional coordination: Denver Water must transparently participate in Colorado River compact negotiations and regional water planning, with public reporting on how decisions affect Denver’s long-term supply

International Evidence: Water-Smart Cities

City/Country	Model	Result
Israel	National water conservation mandate. Drip irrigation (invented in Israel) universal in agriculture. Desalination plants provide 80% of domestic water. Wastewater recycling rate: 85% (highest in world).	Turned a water-scarce desert nation into a water-surplus country. Per-capita water use dropped 25% while population doubled. Recycled wastewater irrigates more than 50% of agriculture.
Singapore	”Four National Taps” strategy: imported water, local catchment, desalinated water, and NEWater (recycled wastewater treated to drinking standards).	NEWater meets 40% of Singapore’s water demand. City-state with zero natural water sources now has water security through innovation. Target: 85% non-imported water by 2060.
Melbourne, Australia	Mandatory water restrictions during Millennium Drought (1997-2009). Permanent water conservation rules afterward. Rebates for rainwater tanks and efficient fixtures. Target 155: voluntary 155 liters/person/day goal.	Per-capita water use dropped 50% during drought and remained 30% below pre-drought levels permanently. Culture of water conservation became self-sustaining.
Windhoek, Namibia	Direct potable reuse since 1968 - recycled wastewater treated to drinking water standards. World’s longest-running potable reuse system.	Provides up to 35% of drinking water from recycled wastewater. Proven safe over 50+ years of operation. Model for arid cities worldwide.
Tucson, AZ	Rainwater harvesting required for all new commercial development. Greywater reuse permitted and encouraged. Rebates for xeriscaping.	Reduced per-capita water use by 30% since 2000 while population grew. Demonstrates what a southwestern US city can do when it takes water seriously.

Denver receives less precipitation than Tucson and has done less to conserve. Israel turned a desert into agricultural abundance through technology and political will. Singapore achieved water security with zero natural water sources. Denver has advantages these cities don’t - mountain snowpack, alluvial aquifers, and existing reservoir infrastructure. What Denver lacks is urgency and policy ambition.

How We Pay For It

• Conservation programs and rebates: $5-10M/year (offset by reduced infrastructure costs from lower demand)
• Greywater and recycled water expansion: $15-25M capital investment (phased over 5 years), funded through water utility bonds
• Aquifer storage and recovery: $10-20M capital investment, funded through water utility bonds and federal infrastructure grants
• Watershed protection: $3-5M/year (cross-reference with climate/wildfire policy)
• Lifeline rate subsidy: $5-8M/year, funded by steepened upper-tier rates
• Total city contribution: $10-15M/year in General Fund support; remainder through water utility financing
• Cost avoidance: Every dollar invested in conservation avoids $3-5 in supply infrastructure costs (American Water Works Association). Demand reduction is the cheapest new “source” of water

Frequently Asked Questions

“Denver has plenty of water.” Denver Water’s current supply is adequate under normal conditions. It is not adequate under prolonged drought, which is what climate science projects. The Colorado River basin is in a 20+ year megadrought. Snowpack is declining. Planning for abundance while living in scarcity is how cities end up in crisis. Ask Cape Town (2018 near-Day Zero) or Phoenix (groundwater depletion).

“Isn’t this Denver Water’s job, not the city’s?” Denver Water is an independent utility, but water security is a city responsibility. The city controls land use, building codes, and development approvals - all of which affect water demand. The city also has the authority to advocate for governance reform and to condition development on water efficiency. Leaving water policy entirely to an unelected utility board is a democratic failure.

“Mandatory restrictions are government overreach.” Every western city that has achieved water sustainability has done so through a combination of mandatory standards and incentives. Voluntary conservation has been tried for decades and has not produced the reductions needed. Tucson, Los Angeles, and Melbourne all implemented mandatory programs and saw dramatic results. “Government overreach” is a talking point; running out of water is a reality.

“Greywater is unsanitary.” Greywater (from sinks, showers, and laundry) is not sewage. It is widely used for irrigation and toilet flushing in Australia, Israel, and across the western US. Arizona, California, and New Mexico all have residential greywater frameworks that have operated safely for years. Colorado’s restrictions are outdated, not science-based.

“Why should I conserve when agriculture uses most of the water?” Agriculture uses approximately 80% of Colorado’s water statewide, but within Denver’s municipal system, residential and commercial use dominate. Denver can’t control statewide agricultural water policy, but it can control its own demand. And reduced municipal demand strengthens Denver’s position in Colorado water rights negotiations.

“Aren’t you attacking lawns?” We’re attacking the idea that a city receiving 14-17 inches of rain per year should be covered in grass that requires 30+ inches. Native landscaping is beautiful, low-maintenance, and supports local pollinators. Xeriscaping isn’t gravel and rocks - it’s columbines, prairie grasses, and penstemons. Denver’s natural landscape is stunning. We should design for it, not against it.

References

• Williams, A.P., et al. (2022). “Rapid intensification of the emerging southwestern North American megadrought in 2020-2021.” Nature Climate Change. (Worst drought in 1,200 years.)
• U.S. Bureau of Reclamation. Colorado River Basin water supply reports and shortage declarations.
• Denver Water. Annual reports, long-range planning documents, and Gross Reservoir expansion project updates.
• American Water Works Association. Cost-benefit analysis of demand management vs. supply expansion.
• Colorado Division of Water Resources. Snowpack and streamflow data; water rights administration.
• Singapore Public Utilities Board (PUB). NEWater and Four National Taps program reports.
• City of Melbourne. Water conservation program data and per-capita consumption trends.
• City of Tucson Water Department. Conservation program outcomes and rainwater harvesting ordinance.
• Israel Water Authority. National water economy reports; wastewater recycling data.
• Western Resource Advocates. Colorado water conservation policy analysis.