Water Treatment Plants

HistoryIn 1932 Plymouth constructed its first

wastewater treatment plant

In 1959 they transferred the sewage utilities over to Plymouth Utilities

Reports

Sewage Rates

2012 Drinking Water Quality Report

What’s the Difference?Water Treatment Plant (Lab – Part 1)

Starts in lakes, rivers, or groundwater (“raw water”)

Pumps to a water treatment plantRouted through settling tanks and filtersChlorine is added, and the “finished water” is

ready to drinkPumps, storage tanks and pipes move the

drinking water back into homes, schools, businesses

What’s the Difference?Wastewater Treatment Plant (Lab – Part 2)

Wastewater is drinking water that is used indoors. For example: The water to wash your clothes,

take a shower, brush your teeth, wash your dishes, etc.

Water is put through screens and settles to remove large inorganic wastes (copper, lead, fluoride, nitrates)

What’s the Difference?Use biological processes (bacteria) to

breakdown and remove organic matter (come from industries, petroleum, gas stations)

Settle to remove the natural bacteria

Cleansed water is disinfected back to streamwater quality and is released back into the rivers, lakes

What’s the Difference?Sewage Treatment Plant

The stuff that gets flushed down your toilet.Similar to a wastewater treatment plant, but

with more screens and filtering.When it is all finished, it also gets pumped

back into the rivers and lakes.

Overview

Step 1: Coagulation

Gentle mixing of the water and treatment chemicals.

This causes the impurities and particles to form larger floc particles.

Floc

Clumps of bacteria and impurities that have come together to form a solid mass that can be filtered out.

Step 2 - Sedimentation

These floc particles get increasingly larger and eventually settle out of the water in large sedimentation basins.

Step 3 - FiltrationAfter sedimentation, the clarified water is passed through filters to remove particles of dirt, algae, and harmful bacteria and parasites.

FiltersFilters can be made from sand, gravel, coal, or granular activated carbon.

We will be making a filter tube.

Step 4 – Chemical DisinfectionDisease-causing bacteria, viruses, and parasites are destroyed by disinfection.

Chlorine is typically used for disinfection purposes.

New disinfection technologies may also use ultraviolet light and ozone.

Overview

Water Treatment Overview, featuring Splash

Pre Lab Questions1. What are some various sources of water

pollution?

2. What are some major sources of nitrate pollution?