Clark County Water Reclamation District Las Vegas

The authoritative technical profile of Nevada’s largest wastewater reclamation facility.


FACILITY BASIC INFORMATION

  • Plant Name: Flamingo Water Resource Center (FWRC)
  • Location: Las Vegas, Clark County, Nevada
  • Operating Authority: Clark County Water Reclamation District (CCWRD)
  • Design Capacity: 150 MGD
  • Current Average Flow: ~105 MGD
  • Population Served: ~1.1 million (Residential and Resort Corridor)
  • Service Area: Unincorporated Clark County (including the Las Vegas Strip), Winchester, Paradise, Spring Valley
  • Receiving Water Body: Las Vegas Wash (tributary to Lake Mead/Colorado River)
  • NPDES Permit Number: NV0021911
  • Year Commissioned: 1956


TARGET AUDIENCE

  • Municipal consulting engineers evaluating advanced nutrient removal in arid environments
  • Wastewater treatment plant operators and utility managers
  • Environmental regulators and water resource planners
  • Engineering firms pursuing capital improvement projects in Southern Nevada
  • Researchers studying potable reuse and return flow credit systems


1. INTRODUCTION

The Flamingo Water Resource Center (FWRC) is the flagship facility of the Clark County Water Reclamation District (CCWRD) and the largest wastewater treatment plant in the State of Nevada. Located centrally in the Las Vegas Valley, this 150-MGD facility serves as the hydraulic backbone for the region’s resort corridor—including the Las Vegas Strip—and a massive residential service area. Originally commissioned in 1956 as a modest treatment plant, the FWRC has evolved into a highly complex water resource recovery facility.

The facility holds a unique distinction in the American Southwest: its treated effluent is critical to the region’s water supply portfolio. Through a system known as “Return Flow Credits,” nearly every gallon of highly treated effluent discharged into the Las Vegas Wash and returned to Lake Mead allows Southern Nevada to withdraw an equal amount of potable water from the Colorado River. Consequently, the FWRC operates not merely for disposal, but as a vital component of a closed-loop urban water cycle, maintaining some of the strictest nutrient limits in the nation to protect the ecological integrity of the Colorado River Basin.

2. FACILITY OVERVIEW

A. Service Area & Coverage

The CCWRD serves the unincorporated areas of Clark County, which encompasses the high-density economic engine of the Las Vegas Strip and the surrounding residential suburbs. The collection system spans over 2,400 miles of pipeline and includes nearly 30 lift stations. The service area is characterized by high variability in influent strength, driven by the unique mix of high-volume commercial discharge (hotels/casinos) and typical residential flow. The district serves a population of over 1 million permanent residents plus the fluctuating tourist population, which can exceed 40 million annual visitors.

B. Operational Capacity

The FWRC is designed for a hydraulic capacity of 150 million gallons per day (MGD). Currently, the facility treats an average daily flow (ADF) ranging between 100 and 110 MGD. The plant handles diurnal peaks typical of urban environments, with specific load shavings occurring during major climatic events. While the Las Vegas Valley is arid, the separate sanitary sewer system minimizes wet-weather peaking factors compared to combined systems, though infiltration/inflow (I/I) management remains a priority during rare heavy storm events.

C. Discharge & Compliance

Treated effluent travels via the Flamingo Wash to the Las Vegas Wash, a 12-mile urban river/wetland that flows into Lake Mead. Because Lake Mead is the primary drinking water source for Las Vegas (and downstream users in California and Arizona), the discharge standards are exceptionally stringent under the NPDES permit issued by the Nevada Division of Environmental Protection (NDEP). The facility must achieve high-level removal of Total Phosphorus (TP) and Total Nitrogen (TN) to prevent eutrophication in the reservoir. The plant consistently achieves 99% removal efficiency for major pollutants.

3. TREATMENT PROCESS

A. PRELIMINARY TREATMENT

The headworks facility is designed to protect downstream equipment from debris and heavy solids. The process utilizes mechanically cleaned bar screens with narrow spacing to remove rags, plastics, and large solids. Following screening, flow enters aerated grit chambers where velocity reduction allows inorganic solids (sand, gravel, coffee grounds) to settle while keeping organic material in suspension. The grit is removed, washed, and dewatered for landfill disposal. Odor control at the headworks is aggressive, utilizing chemical scrubbers and biotrickling filters to mitigate H2S emissions near the urban boundary.

B. PRIMARY TREATMENT

Flow proceeds to rectangular primary clarifiers. Here, gravity settling removes approximately 60-70% of Total Suspended Solids (TSS) and 30-40% of Biological Oxygen Demand (BOD). Floating grease and oil are skimmed from the surface. The primary sludge is pumped directly to the solids handling train (thickening and digestion), reducing the organic load on the secondary biological stage. Ferric chloride is occasionally used to enhance settling and aid in preliminary phosphorus precipitation.

C. SECONDARY TREATMENT (BNR)

The core of the FWRC is its biological treatment system, utilizing Activated Sludge with Biological Nutrient Removal (BNR). The plant employs varied configurations, including Modified University of Cape Town (MUCT) and 5-stage Bardenpho processes, to target nutrients.

  • Anaerobic Zones: Promote the growth of Phosphorus Accumulating Organisms (PAOs) for biological phosphorus removal.
  • Anoxic Zones: Facilitate denitrification, where bacteria convert nitrates into nitrogen gas.
  • Aerobic Zones: Provide oxygen via fine-bubble diffusion for nitrification (ammonia to nitrate conversion) and BOD oxidation.

Secondary clarification follows in circular clarifiers, where activated sludge settles and is returned (RAS) to the basins or wasted (WAS) to solids processing.

D. TERTIARY FILTRATION

To meet the ultra-low phosphorus limits required for Lake Mead discharge (often < 0.10 mg/L), the facility utilizes granular media filtration. The tertiary stage employs deep-bed sand/anthracite filters that physically remove remaining suspended solids and particulate phosphorus that escaped secondary clarification. This polishing step is critical for producing “A-quality” reclaimed water.

E. DISINFECTION

The FWRC utilizes high-intensity Ultraviolet (UV) disinfection. The plant transitioned from chlorination to UV to eliminate the formation of disinfection byproducts (DBPs) like trihalomethanes and to improve safety by removing bulk chlorine gas storage. The effluent passes through channelized UV banks where radiation inactivates pathogens (bacteria, viruses, protozoa) before discharge.

F. SOLIDS HANDLING

Primary sludge and Waste Activated Sludge (WAS) are co-processed.

  • Thickening: WAS is thickened using Dissolved Air Flotation (DAF) or rotary drum thickeners to reduce water content.
  • Digestion: Solids undergo Mesophilic Anaerobic Digestion in large enclosed digesters. This process stabilizes the sludge, reduces pathogen content, and generates methane gas.
  • Dewatering: Digested sludge is dewatered using high-speed centrifuges to produce a “cake” with 20-25% solids.
  • Disposal: The biosolids cake is transported off-site for landfill disposal or beneficial use in composting/soil amendment applications, depending on current regulatory allowances and market demand.

G. PROCESS CONTROL

The entire facility is monitored via a centralized SCADA system. Online instrumentation continuously measures Dissolved Oxygen (DO), Oxidation-Reduction Potential (ORP), pH, Ammonia, and Phosphorus levels to allow for real-time automation of blower speeds and chemical dosing pumps.

4. INFRASTRUCTURE & FACILITIES

A. Physical Plant

The FWRC occupies a dense industrial footprint surrounded by residential and recreational zones (including a golf course). This constraint necessitates vertical construction and covered process tanks in many areas. The site includes extensive maintenance shops, a fully accredited environmental laboratory, and administration buildings.

B. Energy Systems & Cogeneration

Energy efficiency is a primary operational driver. The FWRC operates a cogeneration (Combined Heat and Power – CHP) facility. Methane gas produced during anaerobic digestion is captured and treated to fuel internal combustion engines. These engines generate electricity to power plant equipment, while waste heat is recovered to maintain optimal temperatures in the digesters. This circular energy system significantly reduces the facility’s reliance on the commercial power grid.

C. Odor Control

Given the plant’s proximity to the Las Vegas Strip and residential neighborhoods, odor control is paramount. The District utilizes a multi-barrier approach involving:

  • Covering of headworks, primary clarifiers, and solids loading areas.
  • Extraction of foul air to central treatment units.
  • Utilization of biofilters, chemical scrubbers, and carbon adsorption units to treat hydrogen sulfide and organic odors before releasing air to the atmosphere.

5. RECENT UPGRADES & MAJOR PROJECTS

CCWRD maintains an aggressive Capital Improvement Plan (CIP) to address aging infrastructure and capacity needs.

Flamingo Water Resource Center Expansion & Reliability

Timeline: Ongoing (Phased)
Scope: The District has been executing a multi-year modernization program focused on rehab and capacity assurance. This includes the replacement of aging secondary clarifier mechanisms, upgrades to the aeration blower systems for higher efficiency, and electrical distribution improvements.

Paradise Whitney Interceptor (PWI) – $150 Million+

Timeline: Completed 2022
Description: While a collection system project, the PWI is inextricably linked to the FWRC. This 13-mile large-diameter pipeline project conveys wastewater from the growing southwest valley to the FWRC. It involved micro-tunneling under the Las Vegas Strip and airport, ensuring that flow reaches the plant efficiently without surcharging existing lines.

Solids Dewatering Facility Upgrade

Scope: Replacement of aging belt filter presses with high-efficiency centrifuges.
Benefits: Centrifuges produce a drier cake (higher solids percentage), which significantly reduces hauling costs and the volume of material sent to landfills. This upgrade also improved odor containment within the solids handling building.

Future: Advanced Water Purification (Planning Phase)

In collaboration with regional water authorities, future planning considers the potential for direct potable reuse or enhanced aquifer recharge technologies, which would require retrofitting the FWRC with membrane filtration (UF/RO) and advanced oxidation processes, although current return flow credits to Lake Mead remain the primary strategy.

6. REGULATORY COMPLIANCE & ENVIRONMENTAL PERFORMANCE

A. Permit Requirements

The FWRC operates under a strict NPDES permit focusing on nutrient loading to the Colorado River system.

  • Phosphorus: The most critical parameter. The plant must often meet limits averaging 0.1 mg/L to prevent algal blooms in Lake Mead.
  • Ammonia/Nitrogen: Strict limits to prevent toxicity to aquatic life in the Las Vegas Wash.
  • TDS (Total Dissolved Solids): Monitored closely due to the salinity issues in the Colorado River Basin.

B. Compliance History

The CCWRD has an exemplary compliance record, consistently receiving the Platinum Peak Performance Award from the National Association of Clean Water Agencies (NACWA). This award recognizes facilities with 100% compliance with NPDES permits over a period of five consecutive years or more.

C. Environmental Stewardship

The treated effluent sustains the Las Vegas Wash wetlands, a 2,000-acre ecological resource that filters water naturally before it enters Lake Mead. This flow supports native vegetation and provides habitat for migratory birds, demonstrating how wastewater infrastructure can support ecosystem restoration.

7. OPERATIONAL EXCELLENCE

Staffing: The facility is staffed 24/7/365. Operations personnel are required to hold NDEP Wastewater Treatment Operator certifications, ranging from Grade I to Grade IV. The maintenance division includes specialized electricians, instrumentation technicians, and millwrights.

Technology: The District utilizes advanced asset management software to track the lifecycle of thousands of equipment assets. Process optimization is aided by real-time nutrient analyzers that adjust aeration and chemical feed rates automatically, minimizing chemical consumption and energy waste.

8. CHALLENGES & FUTURE PLANNING

A. Water Scarcity and Salinity

As water conservation in homes increases (low-flow fixtures), the influent wastewater becomes more concentrated (higher strength BOD and Ammonia) while hydraulic flow may decrease or stabilize. This “low flow, high load” scenario presents treatment challenges for biological processes designed for more dilute streams.

B. Emerging Contaminants

Like all major utilities, FWRC is planning for future regulations regarding PFAS (Per- and polyfluoroalkyl substances) and pharmaceuticals. Pilot studies and regional collaboration are underway to determine the efficacy of current treatment trains against these persistent compounds.

C. Infrastructure Resilience

The Master Plan focuses on redundancy. With no other receiving water body available, the FWRC cannot bypass untreated water. Therefore, all critical systems (pumps, blowers, power feeds) must have N+1 or N+2 redundancy to ensure 100% treatment during mechanical failures or power outages.

9. COMMUNITY & REGIONAL IMPACT

The FWRC is an economic enabler for Southern Nevada. Without the capacity to treat and return water to Lake Mead, the region’s ability to withdraw drinking water would be severely curtailed. The District engages in public outreach through facility tours for engineering students and community groups, highlighting the “One Water” concept that defines Las Vegas water management.

10. TECHNICAL SPECIFICATIONS SUMMARY

Parameter Specification
Facility Type Advanced Secondary (BNR) with Tertiary Filtration
Design Capacity 150 MGD
Current Average Flow ~100 – 105 MGD
Treatment Process Activated Sludge (MUCT/Bardenpho)
Nutrient Removal Yes (Biological N & P removal + Chemical trim)
Disinfection Ultraviolet (UV) Light
Biosolids Processing Anaerobic Digestion, Centrifuge Dewatering
Energy Recovery Cogeneration (Biogas to Electricity/Heat)
Population Served 1.1 Million+ (plus 40M annual visitors)
Receiving Water Las Vegas Wash → Lake Mead
NPDES Permit NV0021911
Operating Authority Clark County Water Reclamation District
Site Area ~150 Acres


12. FAQ SECTION

Technical Questions

1. What is the hydraulic retention time (HRT) at FWRC?
The total HRT varies by flow but typically ranges from 12 to 18 hours through the liquid treatment train.

2. How does the plant manage Total Dissolved Solids (TDS)?
Wastewater treatment does not typically remove TDS. Salinity management relies on source control (limiting water softeners) and regional management of the Colorado River salinity.

3. What type of aeration system is used?
The plant utilizes fine-bubble diffused aeration powered by high-efficiency turbo blowers to maximize oxygen transfer efficiency in the aerobic zones.

4. Is there a Methanol feed for denitrification?
External carbon sources (like Methanol or MicroC) are available as supplemental feed to drive denitrification in anoxic zones if the influent BOD:N ratio is insufficient.

Public Interest Questions

5. Does the treated water go back into the drinking water supply?
Indirectly, yes. The treated water flows into Lake Mead. Through natural dilution and time, it mixes with the reservoir water before being withdrawn, treated at a drinking water treatment plant, and distributed. This is known as “Indirect Potable Reuse.”

6. Why doesn’t the plant smell bad?
While wastewater has an odor, the FWRC uses extensive covers and air scrubbing systems. The foul air is captured and forced through filters that strip out the sulfur compounds causing the “rotten egg” smell.

7. How is this plant different from the City of Las Vegas plant?
They are separate entities. The FWRC serves the County (Strip, suburbs), while the City of Las Vegas WPCF serves the downtown and northern/western city limits. Both discharge to the Las Vegas Wash.

8. Can I tour the facility?
The CCWRD offers scheduled tours for educational groups and industry professionals. Requests can usually be made through their public information office.

Disclaimer: This article is for informational purposes for engineering professionals. Official operational data should be verified directly with the Clark County Water Reclamation District or NDEP permit filings.