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2.
City Council Combined Special Meeting/Work Session
Meeting Date:
08/21/2017
From:
Erin Young, Water Resources Manager
Department:
Utilities
Co-Submitter:

Information

TITLE:

Water Resources Planning Update.

DESIRED OUTCOME:

Staff is providing City Council with an update on water resources planning for comment and discussion.  A portion of this presentation was provided to the Water Commission on February 16, 2017.

EXECUTIVE SUMMARY:

One task of the Water Services Division is to plan for and provide water supplies and infrastructure to meet the needs of the community on various time scales ranging from near-term to build-out. The Utilities Integrated Master Plan (UIMP) Water Resources Chapter (2011) was an organized effort by staff to ferret unmet water supply needs of the community with various water supply options. Today we find ourselves in a great situation avoiding any rush in to any big decisions, which provides for an excellent opportunity for thoughtful planning. Water Resource planning goals include updating planning scenarios and options, developing objectives of a "One Water" approach, integrating the community into planning, and utilizing a decision model that considers all of the elements of water supply that are important to the Council and community. Completing the various elements in this presentation will result in a strategic plan with options for City Council and the community to consider by 2020.

INFORMATION:

One job of the Water Services Division is to plan for and provide water supplies and infrastructure to meet the needs of the community on various time scales ranging from near-term to build-out. The City has made significant progress in water resource planning, most notable recently may be the adoption of the state's water adequacy management criteria as a sound water management strategy. Water Adequacy rules require a link be made between current water demand, future near-term water demand associated with undeveloped lands within the city's service area, and future long-term water supply availability (i.e. the "wet" water available and associated water rights) as well as demonstrating the financial capability to develop water supplies. Administered through the Arizona Department of Water Resources, the "wet" water supply, or physical water supply, must be proven as a sustainable water source for at least 100 years. Sustainability is considered through ensuring that aquifer levels are maintained at healthy volumes. The City received its Designation of Adequate Water Supply in 2013.

The Utilities Integrated Master Plan (UIMP) Water Resources Chapter (2011) was an organized effort by staff to ferret unmet water supply needs of the community with various water supply options. Future water demands were calculated both by assuming a water demand per-person for the expected future population but also by assuming a worst-case water demand for each land use category in the voter-approved Regional Plan.  A high-level cost comparison of various water supply options was performed, which considered the cost per volume of water saved or acquired, as well as the volume of water saved or available for each. These options were presented in tables that provide the projected water supply deficit along with the volumes of water and costs to save (as through conservation), recycle (as with expanded reuse), or obtain (as with Red Gap Ranch) resources.

In order to demonstrate an adequate water supply to the Department of Water Resources the City demonstrated a mix of adequate supplies, including surface water, sustainable groundwater, and continued reclaimed water use. This analysis resulted in today's supplies supporting a population of about 106,000. The analysis also was conservative in that it assumed the per capita water use in 2011 as the constant per-capita water use in the projections (no further conservation.) At that point the City's Red Gap Ranch property was submitted as the only option that could single handedly provide a substantial volume of groundwater (12,000 acre-feet) available to meeting projected growth at build out.

The mix of water supplies approved under the City's Designation of Adequate Water Supply is not necessarily a final water supply development path for the City but it is insurance. Red Gap Ranch was purchased in 2005 after a drought depleted Upper Lake Mary to historic lows. At the time the City was not prepared to meeting demand without surface water. The City tried for the first time in 2002 to enforce its water conservation ordinance. Customers were not trained in conservation and change and enforcement were difficult.

Today we find ourselves in a great situation and we are not having to rush into any big decisions, which provides for an excellent opportunity for thoughtful planning. The community is increasingly taking water conservation actions and per capita water use continues to drop. The Water Conservation program was expanded by City Council to focus on water efficiency in the non-residential sector. City Council passed 5 new water wells in the City's 10-year Capital Improvement Program, so we can be proactive in providing infrastructure system redundancy. State law is expanding reclaimed water use options by developing advanced water treatment rules. Staff is currently working with consultants on acquiring important cost elements of these and other water supply options such that they can be fairly compared.

Water Resource planning goals and elements of this presentation will result in a strategic plan with options for City Council and the community to consider by 2020. Elements of this presentation were provided to the Water Commission on February 16, 2017 for comment, discussion, and recommendations. The goals of the Water Resources Section are to 1) further the work completed in the 2011 Water Resources chapter of the UIMP by contracting with consultants for more detailed cost estimates of the various water supply options, 2) incorporate objectives of a "One Water" approach, 3) develop a public involvement plan, and 4) create a decision model.

Master planning is an iterative process and the Council-adopted Water Policies calls for the Water Resources chapter to be updated every five years such that subsequent UIMP chapters are continually based on refreshed information. The 2011 chapter pointed at numerous water supply options evaluated at a high-level cost benefit comparing the volume of water to the cost per one acre-foot of water (325,851 gallons), over a 10-year period. Staff are expanding this work to meet the goals presented above, to include the following:

Updating the Water Resources chapter with:
  • options for a sustainable water budget that considers new regulations or city or community values and objectives
  • a revised water demand analysis based on the voter-approved Regional Plan 2030 land uses
  • growth and water supply tracking as per the city's Designation of Adequate Water Supply
  • groundwater modeling supply sustainability scenarios, considering climate change and environmental impacts
  • watershed and water supply monitoring and management
  • updated supply cost-benefit alternatives that compare water management options economically (capital costs, operation and maintenance costs, avoided costs, life-cycle costs) and financially (the mechanisms to fund projects), expanding to include new alternatives that coordinate with proposed state law regulations around direct and indirect potable reuse
Incorporating objectives of a "One Water" approach that:
  • integrate management of resources and city-wide policies
  • balance environmental, economic, and societal goals
  • improve health of local watersheds
  • improve water supply reliability
  • implement, monitor and maintain a reliable wastewater system
  • increase climate resilience
  • increase community awareness and advocacy for sustainable water
Developing a public involvement plan that would:
  • continue to share results and seek input from the Water Commission
  • encourage the public to attend presentations given to the Water Commission
  • utilize the Community Water Forum, as an example, as a public outreach opportunity to share elements of water resource planning through community discussions
  • request review of the updated Water Resources Master Plan from stakeholder groups
Developing a decision model that may consider factors such as:
  • Environmental criteria including effects on groundwater levels and spring flows dependent on the c-aquifer, water, energy, and material consumption, greenhouse gas emissions arising from water. wastewater. stormwater. infrastructure, sludge processing, infrastructure materials, recycling of materials, water quality health of effluent dependent wetlands
  • Economic criteria including life cycle costs (capital, operation & maintenance, and disposal costs), financial risk exposure, economic return to the city per gallon of water
  • Social criteria including health and hygiene, user affordability, ability to meet environmental regulations, acceptance of water restrictions, public awareness, public acceptance
  • Risk-based criteria and resilience towards natural changes, supply reliability
  • Functional criteria such as yield, number of uses appropriate for the supply, performance, potential for growth, proximity to existing infrastructure, regional compatibility

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