County Water
& Sewer District


Wastewater Treatment Plant Upgrade Project System Information

This web page has information about the wastewater treatment plant project that the River Rock County Water & Sewer District has been working on for many months.  Each section below provides information about the treatment plant upgrade, project costs and the bond election vote in September.  If you have specific questions about the project please email us at


The River Rock Subdivision was originally approved by the Montana Department of Environmental Quality as a subdivision that would be served by a central sewer collection system.  An aerated lagoon was also approved as the treatment system for the wastewater collected.  The District has 2 aerated lagoons, a primary and secondary lagoon which hold and treat wastewater.  Wastewater effluent leaves the second lagoon and gravity flows into a series of infiltration beds. The effluent then seeps into the ground through the bottom of the infiltration beds.  The image below shows and aerial view of the lagoons and infiltration cells.

The Montana DEQ issued a wastewater discharge permit since the wastewater is discharged into the groundwater.  The discharge permit has a list of water quality parameters that must be consistently met to remain in compliance.  The River Rock lagoon system has not been able to meet the permit limits for total nitrogen and coliform bacteria.  The Department issued a new groundwater discharge permit that went into effect on April 1, 2010.  In the new permit, because of water quality standard violations, the DEQ has included a compliance schedule to get the system into compliance with the permit limits.  The compliance schedule gives River Rock until October 2013 to have a system that meets permit limits.  A complete copy of the discharge permit is provided at the link below.  The compliance schedule is on pages 7 and 8 of the permit.

» River Rock Groundwater Discharge Permit- April 10, 2010


The District subsequently hired Morrison & Maierle to evaluate the current system and to complete a Preliminary Engineering Report (PER).  In the PER the engineers concluded that the current lagoon system would not be able to meet the discharge permit limits.  They have recommended building a Membrane Bio-Reactor (MBR) treatment plant as the best cost option.  This treatment plant will replace the aerated lagoon treatment system.  The plant will be initially constructed to handle 200,000 gallons per day and is expandable to 375,000 gallons per day which was approved by DEQ as the full build-out capacity.  The new treatment plant will be located at the south end of the lagoon area between the IP cells and primary lagoon.  The map view below shows the footprint of the new MBR plant.  The access to the plant will be changed to the south of the plant into North River Rock Drive.  Morrison & Maierle has completed plans for the new plant and will be submitting these plans to DEQ within the next couple of weeks.  DEQ will then review and approve the plans after their comments have been addressed.




The total project cost is $4,195,255 as shown in the table below.  This total include administration, engineering, construction and a contingency This cost will be funded by a State Revolving Fund Loan backed by General Obligation bonds.  The SRF loan program has also told River Rock that $300,000 will be "forgiven" from the loan repayment schedule.  This reduces the amount the District needs to borrow to $3,830,220.  To issue the bonds the District must pass a bond resolution, hold a public hearing and conduct an election which must be passed by it's residents and property owners. The District passed a bond resolution on June 27, 2011.  A copy of the full resolution is provided at the link below.  The election procedure is discussed in more detail below.  

» District Bond Resolution # 2011-11

Wastewater Treatment Plant Upgrade Project        
Estimate completed by Anna Miller, Montana Dept. of Natural Resources, State Revolving Fund (SRF) Loan Program June 23, 2011
SRF Loan A1  $300,000 SRF Loan B        $543,220
@ 3.75% Int Rate
SRF Loan C        $3,287,000
@ 3.75% Int Rate
from RRWSD
Estimated Administrative & Finance Costs          
Personnel Costs  $           6,000  $                6,000  $                       -      $           12,000
Office Costs    $                   300  $                       -      $               300
Professional Services  $           7,500  $                7,500  $                       -      $           15,000
Legal Costs  $           3,500  $                4,000  $                       -      $            7,500
Audit Fees  $                -    $                     -    $                  1,200    $            1,200
Travel & Training    $                     -    $                     800    $               800
Debt Service Reserve  $                -          $                 -  
Interim Interest  $                -          $                 -  
Bond Counsel & Related costs  $         15,000  $                     -    $                       -      $           15,000
Subtotal Admin/Finance Costs >  $         32,000  $               17,800  $                  2,000  $                  -    $           51,800
Estimated Activity Costs          
PER Update        $                  -    $                 -  
Preliminary Engineering    $                     -    $                       -    $           65,035  $           65,035
Engineering/Arch. Design  $        211,561  $               48,400  $                 12,679  $                  -    $         272,640
Construction Engr. Services  $         56,439  $             235,822  $                 24,240  $                  -    $         316,501
Construction    $                -    $             241,198  $            2,912,044  $                  -    $      3,153,242
Contingency  $                -    $                     -    $               336,037  $                  -    $         336,037
Subtotal Project Activity Costs >  $        268,000  $             525,420  $            3,285,000  $           65,035  $      4,143,455
TOTAL PROJECT COSTS >  $    300,000  $         543,220  $        3,287,000  $        65,035  $  4,195,255
1 SRF Loan A will be "forgiven" for repayment


In addition to the capital costs, the project will add costs to the annual operation and maintenance budget for the wastewater system.  The new plant will add depreciation costs for the new equipment and added costs for labor, power and chemicals.

Annual Replacement & Operation/Maintenance Cost Estimate  
July 21, 2011  
» Click for Detail Cost Estimate  
Annual Replacement Cost Estimates  
Membrane Replacement $21,427
Blower Replacement $6,025
Pump Replacement $13,889
Liner Replacement $12,401
Interior Valve And Piping Replacement $3,985
Exterior Valve And Piping Replacement $5,977
Miscellaneous Sludge Handling Infrastructure Replacement $1,612
Generator Replacement $7,444
Total Annual Replacement Costs > $72,761
Annual Operating Cost Estimate  
Operating Costs- Power, Chemicals & Labor $90,154
Total Operating Power Costs > $90,154
Estimated Impact on Monthly Sewer Rates  
Total Sewer Connections              1,031
Monthly Increase per Connection [(Annual Cost/12)/Connections]  $13.17



The loan costs for a SRF loan for this project are shown below.  The loan amortization is based on a $3,830,220 over 20 years at 3.75%.  The total loan repayment for principal and interest is $5,571,060.  The annual debt service for this loan is estimated at $273,931.  The SRF loan will be backed by General Obligation Bonds (GO Bonds) which are secured by the District's taxing authority.  The Water & Sewer District will have to levy a tax annually to collect enough money to make the annual payment. 


Preliminary Schedule
    PROJECT NAME: WWTP Upgrade     FINAL LOAN PAYMENT: 7/1/2032  
    LOAN AMOUNT: 3,830,220     PROJECT NUMBER: Pending  
    INTEREST RATE: 3.75%     DATE OF FUNDING: 10/1/2011  
              TOTAL TOTAL
1 1/1/2013 $47,878 $35,908 $95,756 $65,149 $3,765,071 $229,412 $229,412
2 7/1/2013 $18,825 $14,119 $37,651 $66,370 $3,698,701 $136,965  
3 1/1/2014 $18,494 $13,870 $36,987 $67,615 $3,631,086 $136,965 $273,931
4 7/1/2014 $18,155 $13,617 $36,311 $68,882 $3,562,204 $136,965  
5 1/1/2015 $17,811 $13,358 $35,622 $70,174 $3,492,030 $136,965 $273,931
6 7/1/2015 $17,460 $13,095 $34,920 $71,490 $3,420,540 $136,965  
7 1/1/2016 $17,103 $12,827 $34,205 $72,830 $3,347,710 $136,965 $273,931
8 7/1/2016 $16,739 $12,554 $33,477 $74,196 $3,273,514 $136,965  
9 1/1/2017 $16,368 $12,276 $32,735 $75,587 $3,197,927 $136,965 $273,931
10 7/1/2017 $15,990 $11,992 $31,979 $77,004 $3,120,923 $136,965  
11 1/1/2018 $15,605 $11,703 $31,209 $78,448 $3,042,475 $136,965 $273,931
12 7/1/2018 $15,212 $11,409 $30,425 $79,919 $2,962,556 $136,965  
13 1/1/2019 $14,813 $11,110 $29,626 $81,417 $2,881,139 $136,965 $273,931
14 7/1/2019 $14,406 $10,804 $28,811 $82,944 $2,798,195 $136,965  
15 1/1/2020 $13,991 $10,493 $27,982 $84,499 $2,713,696 $136,965 $273,931
16 7/1/2020 $13,568 $10,176 $27,137 $86,084 $2,627,612 $136,965  
17 1/1/2021 $13,138 $9,854 $26,276 $87,698 $2,539,914 $136,965 $273,931
18 7/1/2021 $12,700 $9,525 $25,399 $89,342 $2,450,572 $136,965  
19 1/1/2022 $12,253 $9,190 $24,506 $91,017 $2,359,555 $136,965 $273,931
20 7/1/2022 $11,798 $8,848 $23,596 $92,724 $2,266,832 $136,965  
21 1/1/2023 $11,334 $8,501 $22,668 $94,462 $2,172,369 $136,965 $273,931
22 7/1/2023 $10,862 $8,146 $21,724 $96,233 $2,076,136 $136,965  
23 1/1/2024 $10,381 $7,786 $20,761 $98,038 $1,978,098 $136,965 $273,931
24 7/1/2024 $9,890 $7,418 $19,781 $99,876 $1,878,222 $136,965  
25 1/1/2025 $9,391 $7,043 $18,782 $101,749 $1,776,474 $136,965 $273,931
26 7/1/2025 $8,882 $6,662 $17,765 $103,656 $1,672,817 $136,965  
27 1/1/2026 $8,364 $6,273 $16,728 $105,600 $1,567,217 $136,965 $273,931
28 7/1/2026 $7,836 $5,877 $15,672 $107,580 $1,459,637 $136,965  
29 1/1/2027 $7,298 $5,474 $14,596 $109,597 $1,350,040 $136,965 $273,931
30 7/1/2027 $6,750 $5,063 $13,500 $111,652 $1,238,388 $136,965  
31 1/1/2028 $6,192 $4,644 $12,384 $113,746 $1,124,642 $136,965 $273,931
32 7/1/2028 $5,623 $4,217 $11,246 $115,878 $1,008,764 $136,965  
33 1/1/2029 $5,044 $3,783 $10,088 $118,051 $890,713 $136,965 $273,931
34 7/1/2029 $4,454 $3,340 $8,907 $120,264 $770,449 $136,965  
35 1/1/2030 $3,852 $2,889 $7,704 $122,519 $647,929 $136,965 $273,931
36 7/1/2030 $3,240 $2,430 $6,479 $124,817 $523,113 $136,965  
37 1/1/2031 $2,616 $1,962 $5,231 $127,157 $395,956 $136,965 $273,931
38 7/1/2031 $1,980 $1,485 $3,960 $129,541 $266,415 $136,965  
39 1/1/2032 $1,332 $999 $2,664 $131,970 $134,444 $136,965 $273,931
40 7/1/2032 $672 $504 $1,344 $134,444 ($0) $136,965 $136,965
  Totals > $468,298 $351,224 $936,596 $3,830,220   $5,571,060 $5,571,060

The tax levy estimate for the GO bond debt service is shown in the 2 tables below.  To calculate the mill rate to collect $273,000 for bond debt service the total taxable value of the District must be calculated.  The District compiled a list of all parcels in the District that included the market and taxable value for each parcel.  An excerpt from this list is shown below and a link to the full list is provided below.  The sum of all of the taxable values from the 2010 tax year for all parcels in the District was $3,016,565.  Based on this taxable value it would require a mill rate in the amount of 90.81 mills.  The full parcel list has a column that computes the estimated tax cost for each parcel based on a 90 mill levy.

» Full River Rock Parcel List

@ 90.81 Mills
Parcel No
Property ID User Type Market
2010 CRARCONMST 06-0903-03-4-44-07-7000 CONDO     $0
2010 MMM5860 06-0903-03-4-18-37-8481 SFR $26,788 $755 $63
2010 MMM6168 06-0903-03-3-15-09-8055 SFR $25,041 $706 $59
2010 MMM6213 06-0903-03-4-17-69-8256 SFR $27,039 $762 $64
2010 MMM6227 06-0903-03-3-15-49-8001 SFR $14,479 $408 $34
2010 MMM6241 06-0903-03-3-16-31-8001 SFR $14,321 $404 $34
2010 MMM6303 06-0903-03-3-13-42-8056 SFR $14,429 $407 $34
2010 MMM6304 06-0903-03-3-15-13-8013 SFR $14,477 $408 $34

The "Market Value" that is shown on the list is the market value that the Department of Revenue (DOR) assigns to each parcel.  It is not meant to be the value of what your property is worth if you were to sell it today.  The DOR put together a pamphlet which explains property taxes that may be helpful in understanding market and taxable values.  The link is show below.

» Dept of Revenue "Understanding Property Taxes"

The table below shows summary costs for the average types of development in the District.  River Rock has 222 condo units in it that have an average taxable value of $2,273, and 915 Single Family Residences (SFR) that have an average value of $2,748.  The average tax cost for all parcels in the District is $235.74 per year based on the 2010 taxable value.  This is equivalent to $19.65 per month but would be paid twice per year on the semi-annual tax statements that Gallatin County sends out.

Summary of Project Loan Costs & Tax Levy Estimate July 21, 2011  
Total Project Cost for Loan $3,830,220     Total Market Value $110,283,584      
Max Loan Term (Yrs)                         20     Total Taxable Value         3,016,565      
Interest Rate 3.75%     Total Parcels               1,163      
Total Principal $3,830,220     Total EDUs             1,171.0      
Total Interest $936,596              
Total Loan Cost (P+I) $5,571,060     USER TYPE TOTALS & AVERAGES      
Average Annual P&I Payment $273,931         Total Market Total Taxable  
        USER TYPES # Value Value  
GENERAL OBLIGATION BOND % ASSUMPTION     CONDO 222 $17,893,981 $502,286  
% to be funded by GO Bond 100%     PARK 25 $1,711,912 $0  
Loan Period (Years)                         20     SCHOOL 1 $279,614 $0  
Loan Interest Rate 3.75%     SFR 915 $90,398,077 $2,514,279  
Amount funded by GO Bond  $           3,830,220     TOTALS >               1,163 $110,283,584  $          3,016,565  
Annual P&I Payment for GO Bond  $             273,931              
Mill Rate =                     90.81 Mills     Average Market Average Taxable  
Avg Cost per Parcel/Year  $               235.74     USER TYPES # Value Value  
Avg Cost per Parcel/Month  $                 19.65     CONDO 222 $80,968 $2,273  
        PARK 25 $68,476 $0  
        SCHOOL 1 $279,614 $0  
        SFR 915 $98,796 $2,748  
        TOTALS >               1,163    $                 2,596  

Mill Rate Estimate

This table shows how the mill rate is calculated.  The calculation at the bottom shows the mill rate for the average taxable value of all parcels in River Rock.



Engineering design phase and DEQ submittal process July 22, 2011
Election date September 13, 2011
Bid letting October 1, 2011
Bid Award November 15, 2011
Notice to Proceed March 1, 2012
Begin Construction March 1, 2012
End Construction October 15, 2012
Start Plant Up November 1, 2012



    The criteria for a bond election to pass is listed below and is governed by Montana law.

  • If 40% or more of the qualified electors vote, the bond proposition is approved and adopted if a majority of the votes are cast in favor of the proposition.

  • If 30% to 40% of the qualified electors vote, the bond proposition is approved and adopted if 60% or more of the votes are cast in favor of the proposition.

  • If 30% or less of the qualified electors vote, the bond proposition must be rejected.

   » Bond Election Statutory Requirements for County Water & Sewer District Elections (MCA 7-13-2328)


Updated: 11/15/2011

  • How much will this cost me?  The wastewater treatment plant upgrade project will impact customers costs in 2 ways as loan Debt Service & Operating Costs as follows:
         1.  Debt Service for the capital construction and engineering costs of the upgrade which will be paid from a tax levy to property in the District.  This cost is estimated to be $240 per year payable from tax bill collections that occur twice per year.

         2. Operation Costs will increase after the project is complete.  The new treatment plant will require more costs for power, chemicals, labor and depreciation for replacement over time.  This cost is estimated at $13.17 per month for each billable sewer account.

  • Why is this project being funded by a tax levy?.  The general obligation bond option is the least cost option in terms the total principal and interest cost of the life of the 20 year loan.  A revenue bond was another option the District Board considered but the DNRC requires that 120% of the amount owed be collected each year as security for bond holders.

  • What about grant money for the project?   If the project is approved by the voters, the Montana DNRC has committed $300,000 in "loan forgiveness"  which is essentially a grant that does not have to repaid by the District.  The District made an effort to find other grant funds for the project.  In 2010 an income survey was conducted to try to qualify the District for grant money through the federal USDA Rural Development program. The income survey resulted in a Median Household Income (MHI) of $45,147.50.  The cut-off for USDA assistance is a MHI amount of $33,065.  Therefore the River Rock County Water & Sewer District is only eligible for a loan (no grant) at "market rate" which varies by quarter.   USDA provides up to 45% grant assistance and a loan rate at 3.375%  for MHIs between $26,452 and $33,065; for an MHI below $26,452, they can provide grants up to 75% of the project cost and a loan rate at 2.5%.

  • Why are we upgrading the plant? To meet the new discharge permit limits that the Department of Environmental Quality has issued to River Rock for the treatment plant.  For more information please see the discharge permit.

  • How long do we have to pay for this?  The project will be financed as a 20 year project through the Montana State Revolving Loan program.  If the loan repayment date starts January 1, 2013 the last payment will be July 1, 2032.

  • How will this effect our monthly rates?  With the plant upgrade the wastewater system costs will go up in two areas.  The operation and maintenance will require more personnel, chemical and power costs; and for the depreciation of the plant equipment.  The estimated cost per account is $13.17 per month.

  • I live in Landmark what will this cost us?  Nothing because Landmark is served with water only.

  • I live in Cobblestone what will this cost us? Nothing because Cobblestone is served with water only.

  • How and who will count the votes?  The Gallatin County Election Department will administer the mail ballot election.  They will count and certify the election results.

  • What does it take for the bonds to pass? 

    • If 40% or more of the qualified electors vote, the bond proposition is approved and adopted if a majority of the votes are cast in favor of the proposition.

    • If 30% to 40% of the qualified electors vote, the bond proposition is approved and adopted if 60% or more of the votes are cast in favor of the proposition.

    • If 30% or less of the qualified electors vote, the bond proposition must be rejected.

  • When would we have to start paying for this?  If the plant is constructed in 2012 the first payment would be in January of 2013.  So the tax for the bond payment would be on the 2nd half of 2012 tax bill.

  • What happens if the vote fails the first time?  If the election vote fails, the District Board could choose to conduct another election at a later date.  If that election fails, SRF has the ability to loan the money to River Rock without an election if they so choose.  The Board could borrow the money from SRF if SRF is willing to make a loan and repay the loan via a revenue bond.  If SRF chooses to loan River Rock the money after a failed bond election they have two options.  First they could loan the money to RR without requesting another election based on their comfort level with the payment history they have with the District.  Second, they could request that the District conduct another election which would be based on the revenue bond scenario.  The advantage that SRF has if an election is passed in this format is that in the event there is a shortfall in revenue, the Board would have the ability to go to the Gallatin County Commission and request a deficiency tax to recover the shortfall in revenue.  Without an election, the Board would not have this ability.  For more detailed information about the Revenue Bond versus General Obligation bond options click here.

    The District Board does have some alternatives if the election fails.  However, the alternatives require a revenue bond method of financing which, as we determined in the past, is clearly more expensive.  120% of the annual debt service would be required to be held in reserve at all times.  (i.e. one year’s debt service + 20% reserve)

  • What happens if the District does not meet the DEQ compliance schedule?  The Department of Environmental Quality can levy fines for non-compliance.

  • Is this new permit requirement unique to River Rock or is it creating problems for other Districts or towns?  The State has tightened the environmental standards for wastewater treatment plants that discharge to groundwater and/or surface water.  The changes are impacting other communities to upgrade their treatment plants to meet new discharge permit limits.

  • The economy is terrible, why can't the plant upgrade wait until things are better?  Because the discharge permit for River Rock has a compliance schedule in it.  The Montana Department of Environmental Quality is requiring the plant upgrade be done according to their mandated compliance schedule.  Waiting for the economy to improve is not an option.

  • What about using the AlgEvolve treatment system as a cheaper alternative for the River Rock treatment plant?   This issue came up at the public meeting held at the Community Center on August 19th.  Someone from the public who represents the AlgEvolve company asked why it was not considered as a cheaper alternative for the treatment system.  After the meeting the Marty Gagnon, project engineer contacted the Montana Department of Environmental Quality about this treatment technology.  The DEQ review engineer, Jerry Paddock responded by letter on the feasibility of using the AlgEvolve technology to meet the discharge permit limits.    In his letter Mr. Paddock says, "At this time the AlgEvolve treatment system may not be a feasible alternative for the River Rock Water and Sewer District's solution for a new wastewater treatment system due to the fact that DEQ considers this technology to be experimental at this time."  The letter goes on to elaborate on what it would take to develop the technology from an experimental stage through pilot testing.  A copy of the response letter is provided below.
    » DEQ Response Letter

  • Is this project or the money for it related to the Property Owner's Association in any way?  No it is not.  This project does not have anything to do with the River Rock Property Owner’s Association projects.  It is being funded by a general obligation bond which requires a separate mail ballot election conducted by the Gallatin County Election department.

Voting Information


The general obligation bond election for the project cost financing is being conducted as a "
Mail Ballot Election" administered by the Gallatin County Elections Department.  The voting deadline will be  8 PM on February 17, 2012.


     1. Registered Electors Residing in the River Rock County Water & Sewer District

All residents within the District who are registered to vote in the River Rock District should receive a ballot from the Gallatin County election office.  The Gallatin County Election Department will mail a ballot on January 27, 2012 to all residents within the District who are active registered voters. If you have not received your ballot by February 3rd, please call the Gallatin County Election office at 406-582-3060.  If you are not sure if you are registered please call the elections department to check.  If you are not registered please take the time to get registered so you can vote in this important election.

Faxed in absentee ballots will not be accepted.  They must be returned mailed or dropped off by the deadline.

     2. Nonresident Property Owners Registered to Vote Within the United States

For all nonresident property owners, the only way to vote is to request a ballot. To qualify to vote, owners must submit to Gallatin County individual proof of voter registration in the jurisdiction where they are currently registered to vote in addition to their ballot application.  A link to the proof of registration form is provided below. Please mail or fax the completed form to the Gallatin County Election Department.

After it has been approved, the election department will mail out a ballot. If you intend to vote, please send in your "Proof of Voter Registration Form" as soon as possible to allow enough time for the ballot to be mailed back to you, and then for you to mail it back to the Elections Department before 8 PM Friday, February 17, 2012

Click here for Absentee Ballot Request Form » NONRESIDENT Landowner Ballot Request Form

Click here for Absentee Ballot Request Form » CORPORATION Ballot Request Form

     3. Corporate Voting

The president, vice-president, or secretary of any corporation owning property within the River Rock County Water & Sewer District may vote on behalf of the corporation. Contact the Gallatin County Election Department for further information at (406) 582-3060.


If you have questions about the voting procedure, or the mail ballot election please contact:

   311 W. Main, Room 210
   Bozeman, MT 59715

   Tel. (406) 582-3060
   Fax (406) 582-3068


   Website:  Election Department Website

Additional Information & Linked Documents

PDF File Links to the following documents:



For more information contact:

Department of Environmental Quality
Jenny Chambers

Water Protection Bureau
1520 E 6th Ave
PO Box 200901
Helena, MT 59620-0901
Tel.(406) 444-3080

Gallatin County Elections Office
Charlotte Mills

311 W. Main, Room 210
Bozeman, MT 59715
Tel. (406) 582-3060
Fax (406) 582-3068
Website: Election Department Website

Project Engineer
Marty Gagnon

Morrison & Maierle
2880 Technology Blvd. West
Bozeman, MT 59718
P.O. Box 1113
Bozeman, MT 59771
Tel. 406-587-0721

River Rock County Water & Sewer District
265 North River Rock
Belgrade, MT 59714
Tel. 406-581-7644