Tuesday, May 19, 2015

Water, Water Everywhere

When we all moved into Autumn Walk a few years ago Howard County had been under water restriction constraints for several summers in a row, with severe curbs on outdoor watering and car washing through 2012.

But the area wasn't suffering from drought, so why were we under restrictions?

It was a function of how we get our water: most of the public water in Howard County comes from the Baltimore system, and the supply lines were being upgraded or repaired during that period.

Howard County's Water Supply
Most of the heavily-populated, eastern third of Howard County (which includes Columbia, Ellicott City, Elkridge, Jessup, Savage, and our own North Laurel) gets its public water supply from Baltimore City through large water mains.

From the 2013 Howard County Water Quality Report (PDF)

A small sliver of the County east of I-95 and south of Patuxent Range Road (which runs just above MD-32) obtains its water from the Washington Suburban Sanitary Commission (WSSC). This area includes the eastern side of Emerson across from us.

There is no public water in the western part of Howard County, where they rely on wells and septic tanks, and emergency tanks are kept filled at strategic locations for firefighters to use.

Water Restrictions
Water restrictions were placed on Howard County starting in 2010 because one of the two 36-inch mains supplying Howard County from Baltimore had to be replaced. This was a large project that took several years to finish completely.

During this period only one primary water main was in service, greatly restricting capacity, but the work was finally finished by 2013.

Since then Howard County has also committed to drawing a greater volume of water from the WSSC on a sustained basis.

From the Baltimore Water Quality web site

Baltimore's water system draws water from several large reservoirs north and west of the city (Liberty, Loch Raven, and Prettyboy Reservoirs), with forested land providing natural filtering of the surface run-off.

The Susquehanna River which flows southward from Pennsylvania provides back-up water supply when the reservoirs run low.

Reading Your Water Bill
If you look at your water bill, you'll see that water and sewer rates went up slightly in July 2014, but still remain very cheap.

Summer water rates are now $2.15 for every 100 cubic feet from May 1st through October 31st, and winter rates are $1.93 per 100 cubic feet the rest of the year.  Sewer rates are $3.10 per 100 cubic feet.

There are also fixed charges for the water ($14.57) and sewer ($11.13) connections, plus a $15 Bay Restoration Fee from the State of Maryland (colloquially called the "flush tax").

History: Baltimore's Johns Hopkins University and Chlorination
As an aside, Baltimore's public water system had an important role in one of the great public health stories in recent history.

Prior to the beginning of the 20th Century, water-borne diseases were frequent in every country, with millions sickened and often dying from typhoid, cholera, dysentery, and other such diseases. Children were particularly susceptible, contributing to the high infant and child mortality rate.

By the late 1800’s many had come to believe that chlorinating drinking water supplies - infusing the water with a certain amount of chlorine solution or gas - could make the water safe to consume.

Abel Wolman (via Chi Epsilon
Civil Engineering Honor Society)

But the process was haphazard until Abel Wolman, a professor at The Johns Hopkins University in Baltimore, began working in the 1920's to develop a standardized methodology for calculating the chlorination needed in local systems.

His engineering process, which allows local systems to adjust chlorination on the basis of regular water samples, was used to make Baltimore's century-old water system safe, and is still used around the world today.

As a result of his work, we take for granted today in the United States that our public water supply is safe for drinking.

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