City of Scottsdale Salinity Pilot Rebate Update Chris Hassert, PE - - PowerPoint PPT Presentation
City of Scottsdale Salinity Pilot Rebate Update Chris Hassert, PE Planning & Engineering Director OCTOBER 2016 Why Reuse Water Salinity Matters Reuse water is a large (and essential) part of Scottsdales water portfolio and is used
Groundwater recharge Turf/golf course irrigation
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Rebate - Replace softeners with new high efficiency softeners Rebate - Subscribe to a portable exchange service Rebate - Remove salt-based water softener
ID Opt Rebate $ Total Processed Spent $ High Efficiency Upgrade 1 $50 19 $950 Portable Exchange Service 2 $100 4 $400 Softener Removal 3 $125 156 $19,500 Removal, 2nd Payment 3 $125 150 $18,750 Total Apps: 179 $ 39,600 ID Remaining Allowed % Used Total Rec'd Denied % Denied HE Upgrade 281 300 6% 56 37 66% PE Service 96 100 4% 4 0% Removal 44 200 78% 193 32 17% 2nd Payment 75% 6 3% 253 75 30%
SCOTTSDALE UNSALTED 2-Year Salinity Rebate Pilot Program Summary Report
October 2016
Table of Contents
Executive Summary………………………………………………….. 1 Section 1 – Salinity in Arizona and Existing Efforts ………………... 4 Section 2 – Scottsdale Water Salinity Rebate Program Overview ….. 7 Section 3 – Full 2-Year Salinity Rebate Program Results …………..15 Section 4 – Program Take-aways and Lessons Learned …………….19 Section 5 – Conclusions & Next Steps in Salinity Management ……21
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EXECUTIVE SUMMARY
On March 18,, 2014, the Scottsdale City Council adopted Ordinance No. 4146, amending City Code Chapter 49, Water, Sewers, and Sewage Disposal, to allow for a salinity reduction rebate program to be effective July 1, 2014. Under the new Ordinance, a two-year pilot rebate program was introduced to achieve the following goals: Educate Scottsdale Water customers on the detrimental impacts caused by increased salinity in our water cycle. Offer a variety of rebates designed to reduce the addition of salts in our water cycle. Learn from customer feedback and pilot program results and apply those lessons learned to future actions regarding salinity. The need for this proposed Ordinance stems from elevated salinity, or salts, in the sewage stream entering the Water Campus Reclamation Facility (the Campus). Salts are not removed through the traditional reclamation process, and must be addressed using the expensive advanced treatment technologies in place at the
reuse flow stream. Reuse water is a large an essential part of Scottsdale’s water portfolio, because reuse water is used for groundwater recharge and turf/golf course irrigation. As the salinity concentration in the sewage stream increases, reclamation treatment costs rise, since resultant degraded/saline wastewater is costlier to treat and creates a solids disposal issue stemming from reverse osmosis reject water. In developing the salinity rebate program (the program), Scottsdale Water evaluated several strategies to reduce salinity at the source. To gain a better understanding of the viability of these strategies, including cost effectiveness and customer satisfaction, a two-year pilot rebate program was developed offering three specific rebate measures. These measures were focused on reducing salt loads entering the sewer system, while offering the customer a range of options depending on their personal water quality preferences.
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The three rebate measures offered to Scottsdale Water customers are listed below. (1) Ion exchange water softeners with improved Efficiency (2) Portable Exchange (PE) water softening Service (3) Removal of ion exchange based water softeners The table below summarizes the rebates issued as of June 30, 2016 which represents the official end of the rebate program.
ID Opt $ Total Processed $ Remaining Allowed % Used Total Rec'd Denied % Denied Pending With- drawn 8 1 $ 50 19 $ 950 281 300 6% 56 37 66% 9 2 $ 100 4 $ 400 96 100 4% 4 0% 10 3 $ 125 156 $ 19,500 44 200 78% 193 32 17% 5 11 3 $ 125 150 $ 18,750 75% 6 3%
Total Applications:
179 $ 39,600 253 75 30% 5 Rebate ID: 8 High-Efficiency Upgrade 9 Portable Exchange 10 Removal 1st Installment 11 Removal 2nd Installment
By inspection, the outright softener removal rebate has been the most widely applied-for option. Although this was not a surprise, the extraordinarily low number of applications for the Portable Exchange (PE) system rebate did surprise Scottsdale Water staff. Although numerous reasons could exist, the low number is probably best explained by customer aversion to the monthly subscription cost of approximately $40 or more for the service. Even with a 1-for-1 cost match by one
$200 total compensation enough to migrate to a PE service.
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Another significant take-away from the rebate statistics was the high percentage of rejected applications for the rebate tied to improved softener efficiency. Based on customer questions and staff discussions, we’ve concluded the primary reason to be the current disconnect between product labeling and industry cited efficiency
desired efficiency targets (for salt and water use) to efficiency language on the in- store packaging for new water softeners. The approved rebate program budget for FY14/15 and FY15/16 was $82,000 each Operating budget each year, for a total program budget of $164,000.
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SECTION 1 - Salinity in Arizona and Existing Efforts
Increased salinity in water supplies in Arizona, and specifically Maricopa County, is an issue of growing concern. As people try to combat the natural water hardness
levels of salt are introduced into wastewater systems and treatment plants and in many cases back into the groundwater aquifers. The increased salinity negatively impacts the environment and will add significant costs to water utilities as they try to deal with the issue. Fig 1. SOURCES AND CONCENTRATIONS OF SALT IN REUSE WATER
TDS in Reuse 1100mg/ l Raw Surface Water Source 650 mg/l Food Waste & Chemicals in Sewer <50 mg/l Residential & Commercial Softening 350 mg/l +/- Cooling Water Discharges 50 mg/l
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The most dominant residential method of combating hard water is water softening through ion exchange. Self-Regenerating Water Softeners (SRWS) accomplish softening by employing resin to exchange sodium ions for the hardness ions present in the source water. When the resin has exchanged all of its available sodium ions for hardness ions, a regeneration or flushing cycle is required to replace the lost sodium ions. The result is a waste stream of brine and hardness ions discharged to the sewer system. It is through these repetitive discharges to the sewer system that SRWS add more salts to the wastewater stream. High levels of salinity degrade the water quality of reclaimed water which is used extensively in Arizona for water reuse and recharge. Traditional wastewater treatment processes are not designed to address salinity. Elevated salinity concentrations found in sewage translates into elevated salinity of reuse water, unless more expensive advanced water treatment is applied. Scottsdale’s Advanced Water Treatment (AWT) facility features a reverse osmosis system which decreases salinity in water used for golf course irrigation and indirect potable recharge. Scottsdale is unique in that it is the only city in Maricopa County to use AWT technology on reuse water before recharging
controlled, but at a significant cost. Further, the groundwater aquifer does not recognize municipal boundaries and therefore, increased salinity in reuse water recharged by other cities can eventually influence the salinity levels of Scottsdale’s groundwater. The process of removing salinity at the AWT comes with a cost not only now, but in the future. The operating costs to the city can be reduced if salinity in the wastewater stream entering the Campus is reduced. SRWS are estimated to increase the salinity of wastewater in Scottsdale by as much as 300 mg/l. A reduction of wastewater salinity by half, or approximately150 mg/l could reduce the operating costs of the AWT by as much as $200,000 per year. An additional component of cost is involved with treating the brine concentrate in the waste stream (the salt and other constituents removed by the AWT process). Currently this brine waste stream is discharged into a portion of the sewer system which eventually discharges to the 91st Avenue Wastewater Treatment Plant. This wastewater is treated under a multi-city agreement through the Joint Municipal Water Reclamation System with management oversight through the Sub-Regional Operating Group (SROG) Committee. Scottsdale Water recently participated in a SROG led pilot study that determined an additional $90M in capital would be
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required to build technology at the Water Campus capable of further treating the concentrated brine and removing those salts from the local ecosystem. Regionally, salinity has been an area of focus for water professionals for some
evaluate salinity impacts and identify potential remedies. CASS was an active participant in Arizona’s Joint Legislative Study Committee on Water Salinity
(TAC) was formed which produced a document entitled “Strategy for Water Softener Salinity Control and Management”. One of the key findings from this document stated “Managing salinity in Central Arizona is a problem that is becoming increasingly worse over time.” The document further explained that “Salinity is one of the major factors impacting water reuse in the state and particularly the Phoenix Active Management Area, which comprises the greater Phoenix metropolitan area”. Having identified the water quality impacts of increased salinity, the TAC document explored the additional salinity contributions from SRWS. Citing data collected from Scottsdale and Phoenix, the study determined that SRWS significantly contribute to increases in salinity concentrations in wastewater.
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SECTION 2 – Scottsdale Water Salinity Rebate Program Overview
Scottsdale Water evaluated several strategies to reduce salinity at the source. To gain a better understanding of the viability of these strategies, including cost effectiveness and customer satisfaction, staff worked with key stakeholders to develop a two-year pilot rebate program offering three specific rebate measures. Working with Scottsdale Water staff, the participating stakeholders included but were not limited to the Scottsdale Environmental Quality Advisory Board (EQAB), the Water Quality Association (National and Local), Scottsdale Mayor, and his Chief of Staff. The proposed rebates were designed to reduce salinity loading entering the sewer system, while offering the customer a range of options depending on their personal water quality preferences. Listed below are the three rebates offered with pros and cons associated with each rebate. (1) Improved Efficiency Ion Exchange Water Softeners: This rebate is for customers who replace an existing less efficient, earlier generation self-regenerating ion exchange water softener with a new, more efficient ion exchange unit. This rebate allows the customer to continue to address hard water using a SRWS, but replaces older softeners with units that use less salt to remove water hardness. The net result is a modest reduction in added salts to the sewer from those customers choosing this rebate. The key primary goal for Scottsdale Water is to encourage customers to phase out older SRWS units that employ time clocks to trigger regeneration cycles. Time clock based units are undesirable because they backwash and regenerate on a predetermined cycle, even if actual water use suggests that regeneration is not yet
based on actual water demand flowing through the unit.
and have made a decision to take an action that modestly reduces salt discharges to the sewer system.
customer continues to rely on SRWS for addressing water aesthetics
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(2) Portable Exchange (PE) Water Softeners: This rebate is for customers who remove an existing self-regenerating ion exchange water softener and subscribe to a portable exchange service, where the spent resin tanks are removed and replaced by a contracted service provider on a regularly scheduled interval. This rebate still allows the customer to soften their water through ion exchange, but with a portable exchange service, brine laden discharges to the sewer are eliminated directly from the customer’s home. The portable exchange service company replaces the customers spent tanks on a recurring basis and more efficiently regenerates the resin at their central facility.
sewer are eliminated from individual properties, but homeowners are still able to benefit from softened water. The tank provided to the homeowner is filled with charged resin which facilitates ion
longer occurs, the portable exchange company will exchange the spent tank with a replacement tank filled with charged resin and the cycle repeats.
more than $40 per month. Comparatively, a homeowner can purchase salt for a SRWS system for under $15 per month. Some participants could also deem the process as intrusive as the service provider will need to regularly enter their garage if the ion exchange tank resides there. From a water quality standpoint, the portable exchange company will still need to discharge some brine into the sewer system at their centralized processing facility, although there will be a measurable reduction in brine discharge due to the efficiencies realized at the processing facility. (3) Salt-based Water Softener Removal: This rebate is for customers electing to disconnect and remove their existing SRWS. This rebate is for customers receptive to discontinuing ion exchange water softening
that a new SRWS is not subsequently installed at this address within a defined timeframe. To this end, the rebate is paid in two installments. The customer receives half of the rebate upon application approval and initial inspection completion, and the other half approximately one year following a second inspection to confirm no existence of a SRWS.
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advantageous rebate option. Removal of the SRWS system translates into a complete reduction of added salts to the sewer for that property.
with the property if the current owner sells and the new owner wishes to install a SRWS. In terms of water quality, a homeowner who removes their softener will experience high hardness in their potable water. It will be up to the individual homeowner to decide whether or not the hard source water is acceptable or if other
The rebate amount for each of the three salinity reduction alternatives varies, as does the number of rebates available. The lowest rebate amount was applied to the softener efficiency upgrade. The highest rebate amount was applied to the complete SRWS system removal since this choice provides the greatest potential for salinity reduction in the reuse water stream. The table below summarizes the rebates offered and associated dollar amounts assigned to each rebate type. Scottsdale Unsalted 2-Year Salinity Reduction Pilot Rebate Program
customers/year
year), limited to 200 customers in total
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Program Marketing and Advertisement In order to successfully launch the pilot rebate program, Scottsdale Water conducted multiple team discussions and ultimately developed the following advertising and marketing strategy.
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From an exposure standpoint, this strategy was effective in informing customers about the upcoming salinity rebate program, as website hits pertaining to the program passed website hits for all of Scottsdale Water’s water conservation rebates combined.
1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500
Website Statistics
Conservation Home Page Rebate Landing Page Unsalted Landing Page
Program Inception July 1, 2015
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Application Process To apply for a rebate, homeowners were directed to the City’s website where they could access the Scottsdale Unsalted page and print the rebate application. Customers could also call Scottsdale Water’s Conservation office to request the application shown below:
Salinity Rebate Application (Cover and back)
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Customer Survey As a condition of the rebate issuance, Scottsdale Water required each applicant to complete the survey below. The survey is an important component of this
Water staff and used to gauge customer sentiment and attitudes regarding both the rebate program and salinity reduction overall. Through this collected information, Scottsdale Water can better understand customer attitudes and assess what elements of the program can be abandoned, refined, or further developed concerning future salinity reduction efforts.
Salinity Rebate Application (Survey)
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Customer survey responses through the second year of the rebate program were evaluated and are presented in Section 3.0, Full 2-Yr Salinity Rebate Program Results.
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SECTION 3 – Full 2-Year Salinity Rebate Program Results
Upon completion of the two year program, the tables below summarize all rebates issued through June 30, 2016. It is important to note that some second installments will be paid in FY16/17 to customers who applied for the SRWS removal rebate. This is due to the fact that some follow-up inspections will need to be conducted after June 30, 2016.
ID Opt $ Total Processed $ Remaining Allowed % Used Total Rec'd Denied % Denied Pending With- drawn 8 1 $ 50 19 $ 950 281 300 6% 56 37 66% 9 2 $ 100 4 $ 400 96 100 4% 4 0% 10 3 $ 125 156 $ 19,500 44 200 78% 193 32 17% 5 11 3 $ 125 150 $ 18,750 75% 6 3%
Total Applications:
179 $ 39,600 253 75 30% 5 Rebate ID: 8 High-Efficiency Upgrade 9 Portable Exchange 10 Removal 1st Installment 11 Removal 2nd Installment
In addition to the above rebate results, customer survey responses were collected, evaluated and organized into the following pie charts.
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Salinity Rebate Application (Survey Results)
80% 7% 13%
Which aspect of the program did you like the most?
Rebate Amount Application Process Information provided before rebates available 12% 53% 35%
Which aspect of the program did you like the least?
Rebate Amount Application Process Information provided before rebates available
17 8% 19% 62% 8% 3%
I use my water softener primarily for/to:
Aesthetics Control scale Both Neither Other 47% 53%
Do you have a Reverse Osmosis (RO) System?
Yes No 36% 29% 19% 16%
If you purchase bottled water for home consumption, what is the primary reason?
Taste Convenience Quality Other
18 30% 42% 28%
Are you interested in other water conditioning options that do not use salt?
Yes No Undecided 21% 3% 3% 13% 60%
What prompted you to participate in this program?
Help the environment Conserve water Save money Existing unit needed replacement All of the above
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SECTION 4 – Program Take-aways and Lessons Learned
Based on the statistics and interactions from the two year pilot program, the following key take-aways were noted.
salt discharges to the sewer system, customers overwhelming rejected this
monthly cost (typically $40 to $50 per month) and the intrusiveness factor, since the PE provider would require access to the homeowners garage or house on a regular basis.
salt using alternatives to address hard water.
application rejections since customers couldn’t demonstrate that their new softener was better than their old softener, or could meet the identified efficiency standards. This was not the customer’s fault, but our fault and an area that can be improved upon.
sewer and recycled water process
more website hits on Scottsdale Unsalted than all conservation programs combined. Aside from the mandatory customer survey responses, other feedback from customers was collected. The chart below illustrates some of the more common questions and concerns posed by interested salinity rebate customers.
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SECTION 5 – Conclusions & Next Steps in Salinity Management
Based on our two-year pilot program results, the following areas were identified as potential areas of focus.
wish to address hard water
total dissolved solids at the treatment plant level Now that Scottsdale Water is better educated on the perspectives of our residential customers regarding salinity management, we envision salinity reduction
within Scottsdale employ commercial sized softeners and cooling tower units for climate control. Both technologies contribute to brine waste discharged to sewers. The potential gains in salinity management for such resort properties can be substantial, and salinity reduction for one resort property could equate to dozens of individual residential properties. Scottsdale Water should also continue working the Water Quality Association (WQA) with respect to salinity management. In an effort to better educate water softener installers, the WQA recently launched its inaugural certification class. Besides uniform and proper installation, some of class the goals focused on
Capitalizing on this concept, Scottsdale Water is exploring the most practical way to establish a customer rebate for “tune-ups” of existing water softeners. The intent of the rebate will be to assess existing softener units to determine whether or not settings can be “dialed back” to still address hard water but also reduce brine waste discharged to the sewer.
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The above photo was captured at the inaugural State certification session in May 2016 in Phoenix offered by the AZ WQA. The course was designed and offered to interested plumbers, service technicians and installers with the goal of better understanding proper water softener installation and efficient unit programming.