Thank you for taking the time to ask questions about the city’s water treatment plant expansion.  It is extremely important for council and staff to have the input from citizens.

Enclosed is a copy of the responses to your questions regarding the wellfield and water treatment plant expansion from Public Works Director Ken Lanfear.

If you have further questions, you can call me at my office at 997-3416, or contact my secretary, Barbara Miller at 997-3437.

Again, thank you!

Responses to questions contained in the following letters are summarized below.  To avoid
duplication, questions and responses have been grouped according to general categories.

Linda L. Lock, President, Greentree Village, Inc. February 27, 2001
Leigh Deinert, February 28, 2001
Clarence A. Lysdale, March 1, 2001
Dave Franzen, March 1, 2001
Zane Zeimer, President, Citizens For Florence, February 28, 2001
Unsigned, February 15, 2001
Unsigned, February 26, 2001
Richard S. Walker, February 26, 2001
Dave Franzen, February 26, 2001

Heceta Water District
Water Demand
Wellfield
Schedule
Financial
Treatment Plant
Miscellaneous

Heceta Water District (HWD)

Q. Does the City have an agreement to continue purchasing water from HWD?
A. The Council is taking steps to negotiate such agreement.

Q. Is there an agreement between the City and Heceta Water District for HWD to provide water to the proposed Sand Dune and Morales annexations?
A. The City does not plan to remove these properties from HWD at this time.  Agreement for future withdrawal will be a subject for negotiation between the Council and HWD.

Water Demand

Q. Why were average demand values used to determine water facility capacity requirements instead of peak day demand values?
A. Average demand values were not used to determine capacity requirements.  Based on historical water use, a peak demand value of 330 gallons per day per person was assumed.  The peak demand value was computed by using the average value of 188 gallons per day per person multiplied by a 1.75 peaking factor.

Q. Why is the projected demand presented during the February 26th City Council work session different than that contained in the 1998 Water Facilities Plan?
A. Current projected water demand differs from that contained in the 1998 Facilities Plan for three reasons:
 

1. 1998 population projections included the entire UGB.  The City does not currently serve the entire UGB and has no immediate plans to do so.  Therefore, the population projections were revised.  Future water demand was projected using a 3.5 percent per year growth rate in the City’s service area.  This growth rate accounts for both infill plus annexation within the UGB.

2. 1998 projections included an allowance for 0.9 million gallons per day of fire flow.  Emergency storage for fighting fires is provided by the City’s storage reservoirs.  As such, the City does not need treatment capacity to supply this instantaneous demand.

3. Year 2000 population projected in the 1998 Facilities Plan was 7,346.  Actual population was about 7,236. (2000 census announced last week.)

Q. Why is the City expanding the current wellfield and treatment plant if future demand will soon exceed that provided by the expansion work?
A. It is most cost effective to maximize production capacity of the existing treatment facility and wellfield before constructing separate facilities.

Q. Why does the City want to expand net water treatment capacity to 3 million gallons per day if demand will not reach this level until 2008?
A. Water demand is expected to exceed treatment capacity by summer 2002.  Because it is not cost effective to increase capacity in very small increments, capacity would exceed demand until about 2008.  The planned expansion will bring the wellfield and treatment facility to its maximum capacity.

Q. What will be the impact on water demand should below average rainfall occur?
A. Water demand could rise because of increased irrigation.  However, during periods of low
rainfall, conservation measures should be encouraged by the City to minimize increases in water demand.  For example, Governor Kitzhauber has already placed the state on notice that water
conservation measures would be necessary in response to the expected drought this year.

Q. Why were population figures used for demand projections in the Council work session non
consistent with those of the Comprehensive Plan Update?
A. Population figures presented during the Council work session were the latest numbers available.

Q. The 1998 Sewer Rate and Connection Fee Study states that year 2000/2001 wastewater flow was projected to be 956,000 gallons per day.  The report also states that between 80 and 90% of water usage ends up at the wastewater plant.  If this is true, total water use in 2000/2001 should have been between 1,195,000 and 1,062,000 gallons per day.  Does the City really need to be able to produce 2 million gallons per day for 2000/2001?
A. Yes.  Design capacity for water treatment facilities is based on maximum day demand.  The
demand calculated using projected wastewater flow is an average for the year.  Florence has a
maximum to average day peaking factor of 1.75.  Multiplying this by the average demand values above yields water demand values between 2,091,250 and 1,858,500 gallons per day.

Wellfield

Q. What is the anticipated production capacity of the existing wells following rehabilitation given that historical production has been about 130 gallons per minute per well?
A. Following rehabilitation and assuming implementation of an on-going wellfield maintenance
program, average production capacity is expecte4d to be 220 gallons per minute per well.

Q. What is the anticipated long-term production capacity of the new wells?
A. Assuming implementation of an on-going wellfield maintenance program, average production capacity is expected to be 220 gallons per minute per well.

Q. Will there be an impact on well production capacity if the water table drops?
A. Well production capacity can be influenced by water table elevation.  However, minor elevation changes should not impact well production.  In order to significantly impact production a major drop in water table elevation would have to occur.

Q. Will there be an impact on well production capacity if the acidity of rainwater increases?
A. There should be no measurable impact on wellfield production capacity should the acidity of rainwater increase.

Q. Will the City make available a copy of the wellfield test report for public review?
A. Yes. A copy of the report will be made available for review.

Q. Following rehabilitation of the existing wells, will the City provide the public access to daily well production figures?
A. Yes. Daily plant production figures are maintained now.

Q. Was the City Council told of the drop in well production prior to its decision to sever ties with Heceta Water District?
A. The decision to eliminate reliance on Heceta Water District was not based on the City’s water production capacity.  Rather, it was based on Heceta Water District’s inability to provide water to the City beginning the summer of 2002 because of recent limitation set on Heceta’s water withdrawal from Clear Lake.

Q. Are wells 1, 2 and 6 currently producing water?
A. Yes.

Q. Why is the City constructing new wells instead of maintaining the existing wells?
A. The City has initiated an intensive rehabilitation effort to optimize production from existing wells. However, even with increased production from the existing wells, the resulting capacity will not be great enough to meet projected City demand with the loss of Heceta Water District as a reliable source of additional water starting in the year 2002.

Q. What is the life expectancy of the new wells?
A. The new wells should have life expectancies measured in terms of decades.  The City has working wells that have been in service for in excess of 20 and 30 years.

Q. Will construction of the new wells be competitively bid?
A. Yes. new well construction will be competitively bid.

Q. What is the status of purchasing land needed for the wellfield expansion?
A. The City is currently beginning negotiations for securing land needed for the wellfield expansion.

Q. What is the alternative if the wells do not produce adequate water (220 gallons per minute each)?
A. Additional wells could be installed as long as total production did not exceed that allowed by the City’s water use permit.

Q. What “biocide” will be applied as part of the proposed wellfield maintenance regime?
A. Sodium hypochlorite, concentrated chlorine bleach, will be used periodically to control iron
bacterial within the wellfield.

Schedule

Q. What is the current schedule for expansion of the wellfield and water treatment plant?
A. Expansion of the City’s water treatment facilities is scheduled for completion prior to summer 2020.

Q. Why is the current schedule different from others given in the past?
A. The current schedule is essentially the same as past schedules with the main goal being that of increased water production prior to summer 2002.

Q. Why is the City not following recommendations made in the executive summary of the 1998 Water Facilities Plan?
A. The City is essentially following the 1998 Plan.  The recommended alternative outlined in the executive summary of the 1998 Water Facilities Plan is no longer possible due to recent limitations placed on water withdrawal from Clear Lake.  However, the 1998 Plan recognized that construction of a new surface water treatment plant on Clear Lake might not be possible and recommended expansion of the City’s existing facilities should this prove to be the case.

Q. Why has the 1998 Water Facilities Plan not been updated to reflect the change in recommended expansion alternative.
A. It is not necessary to update the 1998 Plan since the City is following recommendations contained in the Plan.

Q. What steps will be taken to protect groundwater at the future (2008) wellfield site?
A. A wellhead protection program will be developed.

Q. How much land will be required for the future wellfield anticipated to be developed by the year 2008?
A. The amount of land required for a future wellfield was conservatively estimated at 300 acres in the Water Facilities Plan.  Exact land requirements will be determined during design of the future wellfield.

Financial

Q. How is the wellfield and water treatment plant optimization work being funded? How will it
impact water rates?
A. Optimization work is primarily being funded by system development charges (SDC’s). There will be no impact on water rates.

Q. How is the wellfield and water treatment plant expansion work being funded? How will it impact water rates?
A. Expansion work is primarily being funded by system development charges (SDC’s). There will be no impact on water rates.

Q. What will be the cost of an on-going wellfield maintenance program?
A. An on-going wellfield maintenance program will cost an estimated $40,000 per year.

Q. How much of the cost of wellfield and treatment plant optimization is attributable to providing water for growth?
A. Wellfield and treatment plant optimization (bringing the production rate to 2 mgd) is being done to meet current water demand.

Q. How much of the cost of wellfield and treatment plant expansion is attributable to providing
water for growth?
A. All of the cost associated with expansion from 2 mgd to 3 mgd is attributable to providing for growth.

Q. What will be the total cost of the future wellfield construction (year 2008)?
A. The 1998 Water Facilities Plan estimated that the future wellfield would cost about $11.5 million and would have a net treatment capacity of 4.7 million gallons per day.

Q. How will the future (2008) water facilities construction be paid for?
A. Future water facilities construction will be funded by system development charges.

Q. How much of the future (2008) expansion work is attributable to providing water for growth?
A. All of the cost associated with future (2008) expansion is attributable to providing for growth.

Q. How will future (2008) expansion work affect water rates (property taxes)?
A. Future expansion work should not impact water rates or property taxes.

Treatment Plant

Q. What deficiencies within the treatment plant have caused lower than expected water production?
A. Deficiencies within the existing treatment plant have included the following:

1.   Pneumatically actuated control valves that provided little control over back washing of the pressure filters.
2. Ineffective air scour systems that resulted in less than optimum cleansing of filters during back washing.
3. Poor flow distribution within the filters resulting from damaged underdrain systems.

Q. What is being done to increase production capacity of the existing water treatment plant?
A. The following steps have been or will be taken to improve treatment plant performance:
 

1. Pneumatically actuated backwash valves on all filters have been replaced with electrically actuated valves. Filter back washing has improved and loss of filter media has been greatly reduced.
2. Air scour systems in filters 1-3 have been replaced and those filters 4-6 will be replaced this spring.
3. Underdrain systems in filters 1 and 2 have been replaced resulting in improved filter performance.
4. Filter media in filters 4-6 will be replaced this spring. Media depths will e modified to achieve higher filtration rates.

Q. Why is the City moving ahead with plans to expand the treatment plant and wellfield prior to proving that 2 mgd net water production can be attained?
A. Due to the reduction in Heceta Water District’s ability to provide water, the City needs increased production capacity by the summer of 2020.  Because of the short time line, the City cannot wait until the end of summer 2001 to move forward with plans for expanding its water facilities.  Public bidding, equipment delivery and construction of the treatment plant expansion will require about 9 months.

Q. What is the expected treatment capacity following optimization?
A. Net treatment capacity is exp3ected to be 2 million gallons per day following optimization.

Q. What is the expected treatment capacity following expansion?
A. Net treatment capacity is expected to be 3 million gallons per day following expansion.

Q. What is the expected treatment capacity following future (2008) expansion?
A. The City’s net treatment capacity estimated for year 2017 is expected to be about 7.7 million gallons per day.  The addition of a new wellfield and treatment facility will account for 4.7 million gallons per day of the total capacity.  A new wellfield and treatment facility would be implemented in phases to match the demand increase within the service area.

Miscellaneous

Q. What steps is the City taking to reduce the amount of leakage within its distribution system?
A. The City has an ongoing maintenance program that repairs leaking system components as they are identified.

Q. Will the City use their surface water permit if 0.8 cfs?
A. The City does not intend to make use of the existing surface water permit.  The permit is for withdrawal in the lower reach of Munsel Creek, where both water quality and quantity are low during late summer when the water is most needed.  Treatment of such surface water for potable use is more difficult and costly than treatment of groundwater.

Q. If the City is successful in reducing water use by 10% as stated in the application for the Water Use Permit, what impact will this have on sewer rates? (Sewer rates are based on water consumption).
A. Sewer rates would not be impacted.  The major reduction would be in peak usage, primarily irrigation.

• City's Second Response to CFF Questions
• CFF's Second Submission of Questions
• City's First Response to CFF Questions
• CFF Questions About City's Water Supply Plan
• North Florence Dunal Aquifer Groundwater Flow Map
• Coming Soon - City's $12 Million Well Development Plan