Memo-P.W.-Engineering Division �
P.W. —F�g�necenng D�s�on
Memorandum
To: Honorable Mayor and Members of the City Council
CC: Rick Getschow, City Manager
From: John R. Bradford, City Engineer���
Date: July 6, 2007 -
Re: Utility Master Plan
This memo summarizes the recently undertaken master planning process for the water and
• wastewater utilities in the City. This memo will outline the goals of each utility as well as the
necessary actions needed to achieve those goals. The memo for the July 14 work session will focus
on budgets and urility rates.
Water Utility
The overarching goal of the water utility is to provide a safe, reliable supply of drinking water to the
residents and business of Hopkins as well as an adequate supply of water far fire protection in the
City. The utility attempts to provide these services as economically as possible.
Existing, Water Facilities
The water system is divided into three categories; Supply, Treatment and Storage, and Distribution.
• Supply includes the wells and piping to the treatment plant
• Treatment and Storage includes chemicals, filters, pumps and water towers
• Distribution includes the water mains, valves, fire hydrants and meters
The City currently has two separate ways to get water into the distribution system; the Elmo site and
the Moline site.
• The Elmo plant is the primary water supply and treatment facility.
o Three Supply Wells (wells number 4, 5, & 6)
• o Two Filter Beds
1
July 6, 2007
• o Chemical Addition
o Four High Service Pumps (into the distribution system)
• The Moline site is for emergencies only
o One Supply Well (well number 1)
o No Filter Beds
o No Chemical Addition
o Two High Service Pumps
The City currently has two elevated storage facilities; the Moline Standpipe and the Blake Tower.
The distribution system consists of more than 43 miles of pipe ranging from 4-inch to 18-inch
diameter.
Operation
All of the systems of the water utility work together to provide a safe and reliabie water supply. The
wells pump water to the treatment plant, where the water is filtered and disinfected. The clean water
is stored on site until it is pumped (High Service Pumps) into the storage towers. The storage towers
drain into the distribution network as water is used. When the tower level falls, more water is
pumped into them. During peak demand, water is pumped most of the day, while the tower level
• continues to fall until it is refilled overnight.
Reliabilitv
Reliability is defined by the amount of water that can be produced with the largest single piece of
equipment out of service for repair. In other words, if something breaks, how much water can we get
to the customers and fire hydrants?
The primary reliability risks to the system include a loss of electrical power, contamination of a well,
and equipment failures. Each of these must be accounted for when planning for a reliable system.
Electrical OutaQe
The loss of electrical power can be a minor inconvenience or a major problem depending on the time
of year and duration of the outage. A short duration event can be covered by the water in the elevated
storage. The tanks can generally be refilled after the event. An outage of several hours or more can
be a big problem if it occurs in the summer during peak demands.
There are three steps to minimize the impact of a power outage.
• Upgrade the Moline site for use in the system
o On a separate electric grid from the Elmo Plant
o Improvements include
■ Chemical Feed Equipment
•
2
July 6, 2007
• ■ Well No. 1 Upgrade
■ Moline Emergency Generator
• Emergency Generator at Elmo Plant
o Operate Plant and Well No. 4
• Emergency Generator Hookups on Wells 5& 6
o Allows for portable generator to connect to these wells
Well Contamination
Well contamination is the most serious event that can happen to a water system. With the wellhead
protection program currently in place, risk of contamination of a well is minimal. However, it is
prudent to plan for such an occurrence. The response to such a contamination would be to shut down
the well in question and check if the Elmo Plant was also contaminated as well as if the distribution
system was contaminated. Without going through all the procedures that would follow, .if the plant
were damaged and repairs were significant (more than a half day in the summer) the following
sources of water would be tapped.
• Moline site
• o Chemical feed and well upgrade from above would have to be done
• Emergency Connections with Neighboring Communities
o Minnetonka — In Place
o Edina — To Be Constructed
o St. Louis Park — To Be Constructed with Atlas Re-development
Eauipment Failures
Equipment failures include everything from a well pump being out of service to storage tank being
painted and everything in between. The two methods for minimizing the impact of the failures is
ensure that an adequate supply of water can be produced with equipment out of service (Reliability)
and to continue to do the major preventive maintenance so that units are operating during peak
demand times.
• Reliability
The only reliability issue in terms of redundant equipment is the filter beds. We had one
filter bed out of service this spring and while we were able to meet water demand at that
time, if it had gone down in the summer, we would have had to either fire up the Moline site,
utilize our connection to Minnetonka, ar issue a watering ban.
•
3
�uiy s, Zoo�
. Additionally, there is a question as to the total water demand required depending on the
strength of redevelopment in the City. It may well be the case that by the year 2030, we
may not be able to meet the maximum day without expanding the plant or instituting a lawn
sprinkling regulation.
Addressing this issue is difficult and expensive. We either need to add another filter at the
Elmo Treatment Plant or provide treatment in addition to the chemical we are
proposing at the Moline site. (Chemical feed only at Moline is acceptable for a few days,
but extended use would require iron and manganese removal).
Because of the expense of this project, we are recommending doing nothing until 2016. At
that point, a study would be conducted to address which alternative (Elmo or Moline
expansion) is most cost effective and provides the best reliability for the system.
Additionally, we will have a better feel for how re-development is impacting water use and
what new treatment technologies are available.
• Major Maintenance
o Dehumidifiers at Elmo Plant
■ Protect piping and electrical equipment from moisture damage
o Annual repairs with street reconstruction projects
■ Repairs conducted while street is torn up
• ■ Voluntary Water Service Replacement Program
o Moline and Blake Towers paint inspections
■ Protect structure from moisture
o Water Map
■ Tool needed for efficient operation of the system
o Hydrant Replacement Program
■ Bring hydrants to current fire fighting standards
o Emergency Chlorine Shut-off Valves
■ Back-up protection for Chlorine Gas leak
■ Allows for re-use of Chlorine containment room
o Meter Replacement Program
■ Updated reading reliability and efficiency
o Rehab Wells 4, 5, & 6
■ Long term maintenance
•
4
July 6, 2007
• o Replace Well Pumps
■ Long term maintenance
o Paint Moline and Blake Towers
■ Protect structare from moisture
Attached is a summary of the Capital and Equipment Replacement expenditures proposed.
Sanitary Sewer Utility
The goal of the sanitary sewer utility is to collect wastewater and transport it to the Met Council
Environmental Services (MCES) facilities in a safe, efficient, and reliable manner.
Existing Facilities
The sanitary sewer collection system consists of more than 43 miles of sewer pipe ranging from 4-
inches to 33-inches in diameter. There are also 71ift stations that pump sewage from low areas into
the sewer mains. The system reliability is good with the appropriate redundant equipment and
emergency generators available. The lift stations are in generally good condition. There are no lift
stations that need additional capacity.
Maior Maintenance and Construction
The major maintenance and construction items include the following
• • Rehabilitate Lift Station No. 4
o Hatch, chains and supports are old and rusted
o Wet well is leaking
o Check Valves need replacing
• Eliminate Lift Station No. 1
o In conjunction with Shady Oak Road project
• Regular Lift Station Major Maintenance
o Need to plan on major maintenance every 12 — 15 years
o Pumps, valves, piping, and other equipment
• Sewer Repairs with street reconstruction program
o Repairs to collection system while street is torn up.
The attached is a summary of the Capital and Equipment Replacement expenditures proposed.
•
5
• H PKIN MI�SOTA �
O S,
WATER ENTERPRISE
CAPITAL AND EQUIPMENT REPLACEMENT EXPENDITURES �
2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2078
CAPITAL EXPENDITURES
Street & Utility Improvements 75000 75000 75000 75000 75000 80000 80000 80000 80000 50000 85000
Weil No. 1 Upgrade (Moline) $27,600
Well No. 1 Emerg. Gen. (Moline) $180,000
Emerg. Gen. Hookups Wells 5& 6 $32,500
Dehumidifiers Elmo Plant $12,000
Moline/BlakeTowerCoatinglnsp. $12,600
Water Map $25,000
3% Hydrant Replacement Program $120,000 $123,600 $127,308 $131,127 $135,061 $139,113 $143,286 $147,585 $152,012 $156,573
St. Louis Park Emerg. Connect. $216,000
, Emerg. Gen. Elmo Plant $378,000
Emerg. Chlorine Shut-Off Valves $48,000
Edina Emergency Connection $64,000
Phased Meter Replacement $137,500 $137,500 $137,500 $137,500
Rehab Wells $140,000
Treatment Plant Study $15,000
Treatment Plant Upgrade $2,000,000
Paint Moline Standpipe $900,000
Paint Blake Tower $300,000
TOTAL CAPITAL EXPENDITURES 5484,700 3576,600 $418,308 $206,727 3210,061 5267,113 $424,786 E505,085 5384,512 52,374,073 $1,285,000
EQUIPMENT EXPENDITURES
1/2 Ton Truck $26,800
Public Works Copy Machine $12,200 $14,200
Hydraulic Jack Hammer $23,500
Telephone System $6,800
Air Compressor $23,100
3/4 Ton Truck $34,900
Radio System $59,700
� Backhoe $134,800
TOTAL E UIPEMENT EXPENDITURES E23100 SO E72 200 530 300 $0 5734 800 $0 E14 200 SO $61 700 $59 700
I � HOPKINS, MINM13L��TA � •
SANITARY SEWER ENTERPRISE `
CAPITAL AND EQUIPMENT REPLACEMENT EXPENDITURES •
2008 2009 2010 2017 2012 2013 2074 2075 2016 2017 2018
CAPITAL EXPENDITURES
Eliminate LS No. 1 $200,000
Rehab Sewer (10% of N'd Areas) $100,000 $100,000 $100,000 $100,000 $100,000 $100,000 $100,000 $100,000 $100,000 $100,000
Rehab LS No. 4 $35,000
Regular LS Major Maint. $15,000 $20,000 $25,000
� Blake Road Sewer Imp. $154,000
TOTAL CAPITAL EXPENDITURES 5100,000 5100,000 $335,000 5100,000 5715,000 b700,000 5120,000 $100,000 5125,000 5100,000 $154,000
EQUIPMENT EXPENDITURES
3/4 Ton Truck $35,700 $33,600
Telephone System $6,800
Generator $26,400
TOTAL E UIPEMENT EXPENDITURES $0 SO 50 S6 800 $0 SO $35 700 EO 533 600 S26 400 SO
I