Linganore Creek Water Treatment Plant by dgz16482


									                       Linganore Creek Water Treatment Plant

                                             Sludge Lagoon

                                              Sediment Pond
                                               25 feet deep
                                             6,000,000 gallons

Clear                                                            Traveling
Wells                     Dual Media                              Screen
                       Rapid Sand Filters
Clear                                             Flash                      Intake
Wells                                             Mixer

Clear             removed
Wells                        Sedimentation        Flocculators
                   during        Basin
Clear             removed    Sedimentation        Flocculators
Wells              during        Basin
                   Sludge                      Sludge Tank - (Vacuum)
Clear             removed    Sedimentation
Wells              during        Basin            Flocculators

        To Frederick City
                                    LINGANORE WATER PLANT

Plant was built in 1931, remodeled in 1947, and again in 1992
The plant uses a Mechanical-Electrical-Chemical Process
Linganore water plant supplies about 3 million gallons of water daily to Frederick City or about half
of what is used daily
The other 2 city water plants are the Frederick Reservoir (about 1.6 millions gallons per day) at
Mountaindale and the Monocacy River Plant (about 1.5 million gallons per day) on                           North
Market Street extended
When the reservoir is down the Linganore Plant produces about 4.6 million gallons daily
Water flows into the plant through a 24” intake from Linganore Creek
Water flows into a traveling screen which is a rotating screen that filters out debris such as
leaves, etc. from the raw water. It is then pumped into the sediment pond
The sediment pond is about 25’ deep where some natural settling takes place
The sediment pond has a capacity of about 6 million gallons (about the amount Frederick City uses
        in a day)
From the sediment pond the water flows by gravity to the Flash Mixer where Aluminum Sulfate or
        Alum, charcoal (activated carbon), and chlorine is added. The alum has a positive
charge and the sediment a negative charge so they are attracted to each other. The charcoal                is
used to take out taste and odor
Raw untreated water from Linganore Creek has a turbidity of 30-50. After first treatment process the
turbidity is at 1. The state minimum standard is .5 (95% of samples must be below this),
however the actual readings on water released to the city is around .05.
The pH of the stream fluctuates between 6.5 and 8.5, after it is treated it is between 7.0 and 7.3
The water then flows into the flocculation tank where flocculators, or large paddles, agitate the
water mixing the alum, charcoal, and the sediment
The water flows into the tanks opposite the flocculation tanks where natural settling takes place. The
sediment from these tanks is taken to the sludge lagoon which must be dredged every 15                     years
or so
The water is drained from the top of these tanks into the Dual Media Rapid Sand Filters which
are inside the building. These filters contain (from top to bottom) 20” of Anthracite, 10-12” of
sand, and 12” of graded sand (fine - medium - large - extra large)
After the water is filtered through the sand filters it goes into the clear wells
Inside the plant chlorine is added twice to kill bacteria, lime is added to adjust pH, fluoride for dental
purposes, and zinc phosphate to line the pipes to prevent lead poisoning
This plant supplies water to the following tanks: Linden Avenue, Butterfly Lane, Carroll Street,
Vernon Avenue, Bowers Road, and Whittier
Education needed for water treatment position: Engineering Degree (Environmental or Chemical)
Education needed for sewage treatment position: Waste water/Biology Degree

                     MONOCACY RIVER


Traveling Screen

                                                      Flash Mixer



                               Sand              Sand
                               Filter            Filter
                               with              with
                               clear well        clear well
                               below             below

Water for this plant comes from the Monocacy River
The plant supplies approximately 1.5 - 2.0 million gallons of water daily to Frederick City
Water from the Monocacy River flows through the intake into the traveling screen which
      removes the larger debris
The raw water is then pumped into the basement of the building where some of the
      chemicals are injected into the water in a horseshoe shaped pipe
The water then travels to the flash mixer where the chemicals are mixed
From the flash mixer the water flows into the flocculation tanks (there are 2 of these)
      where the flocculators, or large paddles, agitate the alum
The water flows into the large sedimentation basin where the alum and the sediment
      forms a floc and settles to the bottom
The top several inches of water in the sedimentation basin flows inside the building into
      the sand filters
Once in the sand filter the water slowly percolates through the sand and gravel which
      filters out the smallest of particles
Beneath the sand filters are the clear wells where the water is stored until it is pumped
      into the large tanks around Frederick City

Chemicals used:

aluminum sulfate (alum) - Has a positive charge to attract the sediment (negative charge)
charcoal (activated carbon) - Removes taste and odor
chlorine - kills germs and bacteria
lime - raises pH
zinc phosphate - coats inside of pipes to prevent lead from entering water
fluoride - prevents cavities in teeth


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