manchester water & sewer department

GOVERNMENT 101SEPTEMBER 2013

MANCHESTER WATER & SEWER DEPARTMENT

Water and Sewer AdministrationResponsible for procedures, programs and planning as well as

the management and supervision of the Department’s operation.

Water TreatmentManage water resources including seven reservoirs and ten wells that can safely provide up to 9.8 million gallons of water per day. Treats and distributes drinking water to the customers taps in Manchester and portions of Glastonbury, South Windsor and Vernon.

Field Maintenance

Responsible for the maintenance of both water distribution and wastewater and collection systems, including water and sewer mains, hydrants, and storage tanks.

Customer ServiceResponsible for all aspects of bill generation and collection for the Water and Sewer Department.

Wastewater Treatment

Responsible for the treatment of wastewater generated by the community in an environmentally safe & cost effective manner.

EngineeringResponsible for the design, inspection and management of projects necessary to replace or recondition water and sewer infrastructure. Perform utility mark-outs and provide records, mapping and permits for connection to the water or sewer system.

LaboratoryThe State certified laboratory is responsible for the daily testing of water and wastewater samples to insure compliance with State and Federal water quality standards.

T&DResponsible for maintenance and repair of the water distribution system. Also small replacement projects.

SLMMaintains and repairs the sanitary sewer lines and manholes and respond to sewer emergencies.

Source of SupplyManages 4,000 acres of watershed land, aquifers, and maintains department facilities.


VISIONTo be considered by our customers and colleagues as

effective, progressive and a leader in the utility industry.

MISSION STATEMENTThe mission of the Water and Sewer Department is to provide the highest possible water quality and customer service at the lowest possible cost, while continuing our commitment to improving the

infrastructure and our community’s environment.

GUIDING PRINCIPLETo continually improve water quality and value to our customers while protecting our natural resources through prudent financial planning, investment in our infrastructure, efficient management

and technical proficiency.

MANCHESTER WATER DEPARTMENT

RESERVOIRS STATIC MIXER

OZONATION FLOCCULATION

SEDIMENTATIONFILTRATIONCLEAR WELLEFFLUENT PUMPS

Coagulant additionCalcium Hydroxide (Lime)

& Chlorine (if required)

Chlorine Addition

LimeZincOrthoFluorideAddition

GLOBE HOLLOW WATER TREATMENT FACILITY FLOW SCHEMATIC

*NOT TO SCALE*

MANCHESTER WATER DEPARTMENT

STORAGE

Manchester Water DepartmentGlobe Hollow Water Treatment Plant

7 Reservoirs• Howard (I-384), Porter, Risley, Lydall 1, Lydall 2, Buckingham

and Globe Hollow • Water flows either by gravity or is pumped to Globe Hollow which

is the terminal reservoir

• Well 1 and Well 2A are groundwater supplies that pump directly into Globe Hollow Reservoir to augment supply during the summer

Raw Water

Depleted reservoir circa 2010 Buckingham @ 30.7%

Manchester Water Department Globe Hollow Water Treatment Plant

• The treatment plant produces between 3.0 and 4.5 million gallons of potable water per day (mgd); it is capable of averaging of 6.0 mgd and has a maximum output of 10 mgd

• We have eight (8) supply wells that are directly pumped into the distribution system

• All of the wells have some form of treatment capability from chemical addition to air stripping

• The production from the wells range from 300 to 600 gallons a minute; a typical residential well produces five (5) gallons a minute

• The wells range in depth of 50 feet deep to 600 feet deep• The amount of groundwater used by the customers ranges from

about 30% of the total water usage in the winter time to about 65% water consumed during the summer time; the remainder of the water consumed is from the surface water supply processed by the Globe Hollow Water Treatment Plant

Raw Water - continued

Manchester Water Department

OZONATION•Ozone is generated on-site by taking liquid oxygen and applying an electric current to it creating O3 from O2

•As raw water passes through the contactors, ozone is bubbled through it

•Ozone is a highly effective oxidizing agent that kills viruses & protozoa

• It removes colors, odors & phenolic tastes from water• It also oxides iron, manganese, sulfides & organics


• Particles in water that add color and turbidity (cloudiness) are too small to filter. Particles need to be made larger

• Water and its constituents are negative in charge• Process of chemical addition electrically stabilizes the water and

creates the large size particles called FLOC. Polyaluminum Chloride (PACL) is used

• Addition of Polyaluminum Chloride (PACL) high in positive charge is used like a magnet to form floc particles

• Streaming current monitor is used to optimize performance, it measures the electrical current or stability of water

Coagulation


• Is the process of slowly mixing the raw water and coagulants(PACL) together to increase the amount of collisions withimpurities so they stick together to form larger, denser thanwater, floc particles. This takes about 20 and 25 minutesafter chemical addition.

Flocculation


• Floc particles are laden with impurities and particulate matter• Sedimentation basins provide time for the floc particles to

settle prior to filtration• Settled floc is vacuumed and sent to the sanitary sewer

using floating siphons• Clarified water overflows these basins and flows to the

filters

Sedimentation

CLARIFIER (typical)


• 2 Filters are each divided into 96 individual cells• As part of the 2010 facility upgrade, the filter was changed over to Granulated

Activated Carbon, a superior filtering agent• Water flows from top to bottom through media that is 11 inches of granular

activated carbon on top of 5.5 inches of sand• As the filter gets dirty water does not pass as easily through it (headloss)• As headloss increases the need to clean the filter occurs• Each filter is washed once per day. It takes about 1.5 hours to wash entire filter• Traveling bridge washes individual cells one at a time using previously filtered

water

Filtration


• Disinfection is the destruction of disease causing organisms called pathogens

• Chlorine is the chemical used to provide disinfection• An upgrade in 2010 to the facility included Ozonation to improve taste &

odor plus add an additional barrier against cysts and viruses• The upgrade also changed the disinfection agent from chlorine gas to

Sodium Hypochlorite (liquid chlorine), a much safer form of the chemical

Disinfection

X XGas Chlorinators Ton Cylinders of Gaseous CL2 Sodium Hypochlorite

Bulk TankSodium Hypochlorite Day

Tank


• Three pumps are used to send water into the distribution system• Filtered water is stored in a clearwell underneath the filters• The clearwell holds 550,000 gallons of filtered & disinfected water• The water level in the Buckland Hills storage tank controls these

pumps; when full, the plant will shut down• When the water level reaches a pre-selected height the plant will re-start

Effluent Pumping

SCADA SYSTEM


Chemicals added to the water leaving the plant are:• Hydrofluosilicic Acid (Fluoride) is used for tooth decay prevention• Sodium hypochlorite is used primarily for disinfection• Zinc orthophosphate is used to diminish the amount of lead and copper in the water by placing a thin film on pipe wall effectively eliminating the contact of water with the pipe

• Lime for pH adjustment (pH control aids the above chemicals in reacting properly and efficiently and also helps to prevent the scaling and/or corrosion of piping)

Post-Filtration Chemical Feeds

Manchester Water Department Globe Hollow Water Treatment Plant

PLANT UPGRADEAfter 27 years, the treatment plant completed its first extensive upgrade in 2011Major Highlights:•Ozonation system for taste & odor improvement plus an extra protective barrier against pathogens•Switchover from gas chlorine to sodium hypochlorite (safety issue) •Building security, accessibility, energy efficiency improvements & new HVAC system•Rebuilt filters and replaced media with GAC over sand•All new chemical storage & feed systems•New emergency generator


CONSTRUCTION PHOTOS

Manchester Water DepartmentField Services Division

• Consists of approximately 278 miles of water main ranging in diameters from 3 inch to 36 inch

• Of which approximately 52 miles were identified to be in need of replacement or cleaning and lining in the Water Distribution System evaluation completed in September 2007

• Based on this report, mains are identified for replacement or rehabilitation

• The Town has established a Water Quality Improvement Program (WQIP) for this purpose and may allocate funds on an annual basis

• With this allocation, approximately 1 mile of main can be either replaced or rehabilitated each year

• There are 1,991 hydrants in the system to provide fire suppression • Ten storage tanks are part of the system with a combined capacity

of 7 million gallons• The tanks are inspected every five years and are painted inside

and out every fifteen years• Annual 12-week water main flushing program occurs each Spring

Water Distribution System


• The system consists of three major pressure and two minor pressure zones

• The low zone is supplied by the New State Road & Love Lane groundwater wells; it serves the western portion of the Town

• The middle zone supplies the center portion of the Town with water produced from the GHWTP

• The high zone supplies the eastern portion of Town with water from the GHWTP and the Progress Drive groundwater well

• The upper Glastonbury and Manchester zones are off-shoots of the high zone and water pressure is boosted by pump stations

Water Distribution System - Continued

Hercules Drive PS NSR Treatment Facility


Water Distribution System Photos

Main Replacement Storage Tanks Hydrants

Valves Pipes


Source Water Protection & Passive Recreation• Approximately 4,000 acres of watershed property

surround our 7 reservoirs• There is a “Passive Recreation Program” and trail

system that allows residents to hike through the watershed property

• Pets are allowed on trails but not in the reservoir or its tributaries; Dog Pond near Howard Reservoir offers aquatic opportunities for canines

• Ten active groundwater wells are located in eight well fields throughout the Town

• The Town has adopted Aquifer Protection Regulations to restrict the types of activities allowed in these areas

• Sanitary surveys, inspections & monitoring are routinely performed to ensure source water protection

MANCHESTER SEWER DEPARTMENT

WastewaterSewers

Grinders Grit Removal Primary Clarification

AerationSecondary Clarification

UV Re-aeration

Final EffluentHockanum

River

DigestionDewatering

Hauling Landfill Disposal

WAS

RAS

Excess Biosolids

MANCHESTER SEWER DEPARTMENTHOCKANUM RIVER WATER POLLUTION CONTROL FACILITY

FLOW SCHEMATIC *NOT TO SCALE*

Manchester Sewer DepartmentHockanum River WWTP

• Design capacity of 8.25 MGD• Peaking factor of 19.2 MGD• Actual flow is 6.2 MGD• Wastewater strength is commonly measured in Biochemical Oxygen

Demand (BOD) and Total Suspended Solids (TSS)• Plant is designed to remove up to 98% of these pollutants

Origin of Flows• Wastewater entering plant is termed influent• Hop Brook Interceptor 40% of Total Flow• North Manchester Interceptor 60% of Total Flow• We also accept nominal flow from neighboring towns

Overview


Preliminary Treatment Process• Hop Brook Aerated Grit Chamber and Comminutor

– Allows silt, sand, and heavy inorganic solids to settle out– Removes debris (rags, sticks, towels, etc.) – The raw wastewater flows by gravity into the Primary Clarifiers

• North Manchester Interceptor Pretreatment Building– Consists of Large Grinder & Bar Rack, Grit removal system, and

aerated grit channels– The function of the units is to remove silt, grit, heavy inorganic solids

and debris – The raw wastewater is pumped to the Primary Clarifiers


Primary Clarification• This is accomplished in large vessels known as primary settling tanks or

clarifiers. They contain mechanisms that concentrate and collect the accumulated sludge and skimmings

• Primary clarification is accomplished by providing a relatively large, quiescent area so heavier organic solids can settle to the bottom to form raw (or primary) sludge and so that “floatables” such as grease and scum can float to the surface for skimming. Both materials will be subject to further processing

• Our facility has two primary clarifiers with a combined volume of 1,300,000 gallons

• This process removes approximately 50% of the BOD & TSS in the wastewater• The wastewater leaving the primary clarifiers is called “Primary Effluent”


Aeration Process• This process consists of 4 basins with each basin having 4 cells equipped

with mechanical aerators. The combined volume of these basins are 2,240,000 gallons

• The purpose is to supply an environment where naturally occurring microorganisms (bacteria) can be cultured to digest the impurities in the wastewater

• We supply air so the bacteria will live and use the organic material in the primary effluent as their food source. The bacteria reproduce, multiply, and attach themselves to food particles. This creates floc particles and collectively is called “Mixed Liquor Suspended Solids (MLSS)”

• The main components of wastewater are carbon, nitrogen, and phosphorus. The plant will remove 99% of the carbon and was designed to remove only one component of nitrogen, Ammonia. New regulations require us to remove a larger percentage of nitrogen. We are currently constructing improvements to achieve denitrification; a process that breaks down Nitrate into Nitrogen gas. Both are harmless when released into the environment. This upgrade will also address Phosphorus removal

• Wastewater leaving these basins is called “Aeration Tank Effluent” or “Secondary Influent”


Aeration Process


The unsung heroes of wastewater treatment:

Paramecium

Stalked Ciliate

Rotifer

Amoeba

Free-Swimming Ciliates

Flagellate


Secondary Clarification• Consists of four (4) secondary settling tanks, (also know as clarifiers) which are

large basins that accept the aeration tank effluent• There are a total of four clarifiers; two 80 feet in diameter and two 90 feet in

diameter. • We normally only utilize the 90 foot clarifiers• The combined tank volume is 1,237,300 gallons• The purpose is to allow the bacteria and biosolids (MLSS) to settle. A portion of

this material is returned back to the beginning of the aeration tanks to help seed the process. This is called “return sludge”. Additional MLSS is created through the biological activity of the microorganisms and must be disposed of; this excess is called “waste sludge” and is sent to the Primary Clarifiers in order to be resettled with the raw sludge & be pumped to the Anaerobic Digesters for further processing at the Biosolids Facility

• This process can remove up to ~98% of the wastewater BOD/TSS• As part of the upgrade, two of the existing smaller clarifiers will be eliminated and

a new third one will be added

Manchester Sewer Department Hockanum River WWTP

Secondary Clarification


• An Ultra Violet (UV) Light process replaced a chlorination system for the purpose of disinfection (kill pathogens)

• It is a physical method of disinfection rather than a chemical process• The main reason for this conversion was for worker/public safety as well as

being safer for the environment • Disinfection of the wastewater occurs as it flows through a narrow channel and

passes by a series of UV bulbs encased in quartz sleeves• Disinfection occurs because the UV light breaks down the cell walls of the

harmful pathogens thus prevents replication or results in cell death• The disinfected wastewater leaving the UV Channel is called effluent

Disinfection Process

← UV Rack in channel

UV Rack removed →


• The purpose of this process is to add oxygen back into the wastewater that was consumed in the treatment process

• This is accomplished passively, by a series of cascading steps in the channel that creates turbulence and puts the wastewater in contact with air from the atmosphere

• It can be supplemented with mechanical aeration if required• The oxygen is added to protect fish and other aquatic life and to put

less of a demand on the receiving waters• The wastewater leaving this process is known as final effluent

Reaeration Tank


Outfall• The outfall is a 30” pipeline which transports the final effluent from the

plant to the Hockanum River.


Primary Anaerobic Digester• Raw and co-settled Waste Sludge from the primary clarifiers are

regularly pumped into the digester• The purpose of the digester is to further reduce the amount of

organic material called biosolids (or sludge) which was removed from the wastewater

• This is accomplished anaerobically (without oxygen) with a group of microorganisms that use the sludge as food and breakdown the biosolids to produce Carbon Dioxide, Hydrogen Sulfide, and Methane

• The digested sludge is then pumped to the secondary digester • The volume of this tank is 1,160,000 gallons• As part of the upgrade, this process will be

eliminated


Secondary Anaerobic Digester• The purpose of this digester is further breakdown the biosolids, settle

and thicken the biosolids and to store methane• The settled biosolids are then pumped to the dewatering building so

water can be mechanically pressed out of the sludge prior to final disposal at the landfill; this will be eliminated during the upgrade as well


Dewatering Process• The purpose of the belt presses are to separate the water from the

biosolids by squeezing water out of the sludge so there is less volume to dispose of

• This is accomplished by first thickening the sludge using an organic coagulant, then distributing it between porous belts that will allow water to pass through but not solids

• The finished product in approximately 14% solids (still 86% water!)• The sludge is then trucked to the landfill for disposal• As part of the upgrade, centrifuges will replace these devices


Cogeneration ComplexMethane from the digestion process can be used as a fuel to power gas-driven generator. The Methane produced during Anaerobic Digestion to yields enough electricity to operate the Anaerobic Digesters and the Dewatering Building. In the process the generator also produces heat. The heat is captured and used to help maintain the temperature (which stimulates gas production) of the biosolids in the digesters. Any excess electricity can be sold back to Connecticut Light & Power.

Manchester Sewer Department Hockanum River WWTPCOMPREHENSIVE PLANT UPGRADE

The last significant plant upgrade occurred in 1991; much of the facility is circa 1970 & beforeCurrently in the Construction PhaseScheduled to be complete by Nov. 2014Major Highlights:• Headworks improvements• Rebuild primary clarifiers• New aerators & modifications to aeration system• Ballasted floc system for phosphorus removal• Improvements to secondary clarifiers• Solids handling improvements including thickeners & centrifuges• Replacement of pumps, valves & other equipment

Manchester Sewer Department Hockanum River WWTPCOMPREHENSIVE PLANT UPGRADE

• Other improvements slated to improve energy efficiency, operability and safety

• New state-of-the-art SCADA System• Partially funded by a grant through the State’s Clean Water

Fund (CWF)

Manchester Sewer Department WWTP Construction Photographs

Manchester Sewer Department More WWTP Construction Pix

Manchester Sewer Department Wastewater Pump Stations

• There are three major pump stations that convey sewage from various areas of Town to the WWTP

• Two Pump Stations were completely rebuilt in 2009 (JC Penney & Love Lane)

• The Birch Mountain Pump Station was replaced in 2012• A fourth pump station was eliminated in 2010 through changes in the

layout of our underground infrastructure

Manchester Sewer DepartmentField Services Division Collection System

• The Town has approximately 165 miles of sanitary sewers• There are approximately 5,000 manholes in the system• The 8th District has about 36 miles of main that they maintain• Approximately 100 miles of sanitary main are cleaned each year• Note: approximately 9 in 10 sewer backups are caused by problems

in the homeowner’s lateral – Call 860-647-3111 first to be sure!

GOOD MANHOLE BAD MANHOLE GIS MAP

MANCHESTER SEWER DEPARTMENT

FOG Program• State-mandated program to reduce the amount of Fats, Oils & Grease from

entering the sewer system• Requires Class III & IV food establishments to have grease traps and

register in the program• This helps to prevent blockages and sewer backups• Reduces O&M costs of collection & treatment systems • Improves public health & sanitation• Helps with compliance of facility discharge standards • Roots are also a major concern but not part of the regulation

MANCHESTER WATER & SEWER DEPARTMENT CUSTOMER SERVICE GROUP

• Billing Section (15,000+ accts)• Metering Section• Backflow prevention and cross

connection program• Precipitation Records• Reservoir and groundwater

levels & withdrawal rates• Environmental recording and

response

MANCHESTER WATER & SEWER DEPARTMENT LABORATORY GROUP

• State-Certified Laboratory• Over 40,000 analyzes performed

per year on water & wastewater• Most testing is performed in-house• Consumer Confidence Report• Ensures compliance with Federal

& State Drinking Water Standards• Ensures compliance with

Discharge Permit• Performs QA/QC testing• Investigate consumer concerns


• Thank you for attending this year’s session of Government 101

• We hope you enjoyed our tours & presentations• Questions or comments?• Don’t forget to fill out the evaluation forms• Please visit our website:

www.townofmanchester.org/water

manchester water & sewer department

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