HomeMy WebLinkAbout03-07-2022 Council Work Session Minutes CITY COUNCIL WORK SESSION
APPROVED
1 CITY OF LINO LAKES
2 MINUTES
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4 DATE : March 7, 2022
5 TIME STARTED : 6:15 p.m.
6 TIME ENDED : 7:45 p.m.
7 MEMBERS PRESENT : Councilmember Stoesz, Lyden,Ruhland,
8 Cavegn and Mayor Rafferty
9 MEMBERS ABSENT
10 Staff members present: City Administrator Sarah Cotton; Community Development
11 Director Michael Grochala; City Engineer Diane Hankee; Director of Public Safety John
12 Swenson; City Clerk Julie Bartell
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14 (5:30 pm) The Rookery Activity Center(visit facility)
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16 1. Water Treatment Pilot Study, Greg Johnson and Ursinio Puga of WSB and
17 Associates Mr. Johnson reviewed the written report noting that in 2021 the council had
18 authorized WSB to complete the pilot study. Mr. Johnson added that the biological
19 filtration process being recommended is already being used effectively in several other
20 cities and has been utilized in Europe for decades. Mr. Johnson and Mr. Puga reviewed
21 a PowerPoint presentation that included information on:
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23 - Raw Water Quality—parameters for monitoring the water for pilot study;
24 focus on removing iron, manganese and ammonia from water; dissolved
25 oxygen and orthophosphate will also be discussed;
26 - What is Biological Filtration—microorganisms are already in the water and
27 need optimum conditions to get to the level to remove; other biological
28 filtration plants in the state;
29 - Conventional Filtration vs. Biological Filtration—comparison table; chemicals
30 are reduced by utilizing biological process; the rest of the process is same
31 minus some of the chemicals;
32 - Pilot Study Goals and Objectives;
33 - Pilot Plant Setup and Operation—view of pilot study testing machine used at
34 Well No. 6; two filter medias were compared; trailer was used for testing;
35 - Pilot Study Results—Found orthophosphate adequate; graph showing aeration
36 requirements; oxygen is added in the form of natural air; iron isn't a big goal
37 because it is already okay; ammonia results also graphed and reviewed;
38 - Financial Analysis—both treatment options include the same steps of treating
39 the water; with biological treatment chemicals are greatly reduced; graph
40 comparing costs for chemicals (inflated numbers used); Mr. Puga noted
41 information from another city that has already changed from conventional to
42 biological filtration and who experienced savings because of the rise in supply
43 costs;
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CITY COUNCIL WORK SESSION
APPROVED
44 - Conclusions;
45 - Recommendation—move forward to biological filtration treatment because it
46 has proven performance and operational savings; recommending silica sand as
47 filter media as it is less expensive and less backwash required with similar
48 performance.
49
50 Mr. Johnson remarked that he isn't aware of any utility that has chosen to switch back to
51 conventional filtering although it is possible to do so.
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53 Mayor Rafferty asked about future considerations. It was clarified that design is intended
54 for the future and growth as well. When the mayor noted the possibility of biological
55 immunity developing, the engineers gave several examples of plants in place for some
56 time and also noted that biological filtration has been used for waste treatment for a
57 century.
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59 Councilmember Stoesz asked about the option of adding softening treatment. Mr.
60 Johnson replied that such an option is available but generally it doubles the cost of a
61 plant.
62
63 The council heard about having satellite plants or having a large single plant.
64 Community Development Director Grochala explained how wells could be staged to
65 maximize available plant(s).
66
67 Staff will come back in April to talk about next steps. The council will be asked to
68 accept the report formally at the next council meeting.
69
7o 2. WBL—Water Appropriation Permit Appeal Update—Community
71 Development Director Grochala reviewed his written report. He explained that the City
72 is under a court order and he reviewed the requirements of the order. A group of cities,
73 including Lino Lakes, appealed the orders in court and, with a hearing pending on the
74 appeal, attorneys are meeting with the judge to see what can move forward. Of great
75 concern are two conditions—prohibition on new well permits within certain areas; and
76 the Minnesota Department of Natural Resources (DNR) is ordered to adjust area
77 withdrawal permits. The DNR, using modeling, indicates a 40%reduction in our existing
78 water use (basically winter use all year and a threat to any water use past domestic use).
79 The DNR has written to the court to discuss the potential ramifications of following
80 through on the court orders. Staff is working with Senator Chamberlain and
81 Representative Raleigh and there is an impactful bill under consideration at the state
82 legislature that would allow cities to continue with their plans while looking at other ways
83 to address the White Bear Lake situation. The discussion is ongoing including with the
84 DNR about trading an older less producing well for a newer better producer. Some of the
85 discussion about where wells could be located has changed because of the treatment
86 option that may occur. Mr. Johnson added that he believes the DNR is gathering
87 information to utilize in discussions with the court.
88
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CITY COUNCIL WORK SESSION
APPROVED
89 Mr. Grochala remarked that there is a lot going and staff may be bringing forward a
90 resolution in support of legislation. Councilmember Lyden noted the difficulty of
91 regulating private wells.
92
93 The council requests that staff keep them informed.
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95 3. Council Updates on Boards/Commissions, City Council
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97 NorthMetro Television—Councilmember Stoesz noted that he was elected to the chair
98 position again;
99 VLAWMO—Mayor Rafferty noted a joint effort for a grant.
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loi 4. Adjourn
102
103 The meeting was adjourned at 7:45 p.m.
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105 These minutes were considered, corrected and approved at the regular Council meeting held on
106 March 14, 2022.
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109 „
110 ,
111 u i e Bartell, Ci Cler R b Rafferty, Mayor
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