Overview
This lecture covers Flagstaff's approach to developing a Reclaimed Water Master Plan, focusing on water resource planning, recycled water options, regulatory framework, technical studies, and community involvement.
Water Resource Planning & Policy
- Flagstaff’s water supply planning emphasizes drought resilience using reclaimed water.
- Designation of Adequate Water Supply includes criteria: continuous availability, legal and physical availability, water quality, and financial capability.
- City code incentivizes reclaimed water use for irrigation and groundwater recharge.
- Policies promote maximizing storage and recovery of reclaimed water to ensure long-term sustainability.
Reclaimed Water Options & Technical Analysis
- Annual single-family water use has declined by 1,000 gallons per household over 20 years.
- Alternatives for recycling water include: direct reuse, streambed recharge (with/without advanced treatment), recharge wells (with/without advanced treatment), augmentation, and direct potable reuse.
- Technical studies conducted: alternatives analysis, biosolids master plan, aquifer recharge feasibility, and reclaimed water master plan.
- Treatment options evaluated include RO (reverse osmosis) and ozone-biological filtration, with associated costs and feasibility.
Aquifer Recharge & Feasibility Studies
- Goal: Recharge 100% of excess reclaimed water to the C aquifer within the city’s groundwater capture zone.
- Studies include infiltration tests, flow impact assessments, and recharge effectiveness modeling.
- Two types of recharge facilities: constructed (engineered) and managed (natural channel).
Community Engagement & Stakeholder Input
- Stakeholder process gathered input from the public, technical experts, and Indigenous community members.
- Workshops and focus groups developed ranking criteria: water quality, sustainability, efficiency, aesthetics, respect, and equity.
- Evaluation matrix used to compare reuse alternatives on multiple criteria.
Challenges, Lessons & Next Steps
- Key concerns: water quality, costs, energy use, public perception, climate change impacts, and regulatory compliance.
- Priority to continue data collection, refine alternatives, and seek further community and council input.
- Ongoing efforts to manage biosolids and validate wastewater capacity projections.
Key Terms & Definitions
- Reclaimed Water — Treated wastewater used for beneficial purposes like irrigation or aquifer recharge.
- Aquifer Recharge — Adding water to underground aquifers for storage and later use.
- Direct Potable Reuse — Treating reclaimed water to drinking water standards for direct supply.
- RO (Reverse Osmosis) — Advanced water purification process.
- Managed Recharge Facility — Uses natural stream channels for groundwater recharge.
- Constructed Recharge Facility — Engineered facility for controlled aquifer recharge.
- Indirect Reuse — Using reclaimed water that’s been stored underground and mixed with groundwater.
Action Items / Next Steps
- Continue technical data collection for evaluating alternatives.
- Hold a city council retreat to discuss findings and options.
- Advance the wastewater biosolids master plan and infrastructure planning.