Virginia Rural Water Association Water Page
Meet the VRWA Water Circuit Riders
Mark Norris & Kenny Reynolds provide technical, managerial and maintenance assistance primarily to publicly owned, Rural Development eligible rural and small water systems in the Commonwealth of Virginia. Together Mark & Kenny work to better serve the water systems in the Commonwealth through training and on-site assistance.
Technology—Where
Do We
Go from
Here?
by Mark Norris, VRWA Circuit Rider II
Recently
a friend and I were discussing the advancements in technology for both personal and
professional uses. We were discussing an old friend of mine who was a mathematical genius;
he was attending William and Mary while I was in high school. While at his parents’
house one evening, he was showing me a math problem that he had spent an extensive amount
of time working on and the work he had done was on small manila cards about the size of an
envelope. He had about five or six shoe boxes filled with these cards. I remember the one
thing he said was if these cards were out of order he would have a heck of a time getting
things to work. It would take a card by card review to get them back in order. Those cards
had all the data he had collected punched into them. Now you have computers that can fit
in your hand that can do many times more than that.
Now, I can sit at my desk while hooked
to the internet and research information from thousands of sources, I will be sending this
story in by e-mail. As well as keeping in touch with various systems in the state
instantly. I just finished booking hotel rooms for this week all from the comforts of
home. My Dell Axiam is sitting in its cradle loaded with contacts and scheduled
appointments; I can check e-mail while out in the field, take pictures of certain
situations and send them to vendors or decision makers back at the office. Software makes
keeping records for reports to the Health Department, DEQ, committee meetings, or for Town
Councils a breeze. My cell phone keeps me accessible in the field.
Reading water meters by hand required
many employees to be tied up for days and then using more time to correct mistakes. The
clerks in the office would take days to enter the data by hand. Now one person can drive a
truck through town in less than half a day, the readings are downloaded by a computer,
totaled and entered into a data base that creates the bills in minutes without mistakes
(on the computers part). Geographical Information Systems (GIS) can access information on
location and sizes of pipes, hydrants, meters, valves, manholes, lift stations, sewer
lines with the touch of a few buttons. All that data can be sent to engineers for project
planning.
SCADA (Supervisory Control and Data
Acquisition) Systems allow for remote access to monitor your systems performance or you
can control pumps and valves or your treatment process from one location. As you can see,
it would be quite difficult to address the many and varied applications of technology in
the Public Utilities field. I would like to briefly discuss a few of the implications and
impacts in using technology in providing service to the public.
First you want to evaluate your needs
and then find the appropriate software to meet just that. Technology is just like any
other business and it can come with many bells and whistles. This can come with a hefty
price tag. Don’t pay for more than you need. Remember, simpler operation and less
costly solutions is the key for software. At the rate of obsolescence, you want to
purchase what is efficient and effective.
Secondly, I would like to look at
whether technology is a blessing or a curse. Let’s look at e-mail. It can be a very
effective tool for communication when it is used appropriately. But the amount of e-mail can be so great that it can
decrease our efficiency. With all the information that is being generated, how can you
determine what you need to know from what others think you should have to know? Having to
much information can be as bad as having to little.
There is no reason to doubt that technology helps the quality and delivery of the services provided by a public utilities organization. But it is important to remember that it is just a tool to be used in accomplishing what we do. But it is still the people in our industry that make the real difference.
SWater Storage Tanks
Too often one of the areas in our water system that we tend to overlook is our finished water storage tanks. These tanks may be either ground storage tanks or elevated storage tanks. The ground storage tanks in a water system are to help compensate for fluctuations in demand for water in the distribution system. These tanks may be made of concrete or steel, and are constructed at, or slightly below ground level. A ground storage tank at a water treatment plant may also be called a clearwell. Elevated storage tanks constructed of steel and/or concrete are often preferred over ground storage because not only do they compensate for fluctuations in demand for water in the distribution system, but provide pressure without pumping. This is especially valuable during power outages in a water system.
Sanitary precautions should be taken when locating a tank site and during construction of a ground water storage tank in the distribution system. Ground water storage tanks may act as elevated storage tanks depending on the elevation of the area that they are built on, and the elevation of the residents’ homes, or businesses they serve. Ground water storage tanks are more economical to construct and maintain than elevated tanks. Any cracks or leaks that appear in a submerged ground water storage tank should be immediately investigated and repaired to avoid any contamination to its contents.
Elevated storage tanks help set a constant pressure in the distribution system, even when distribution system pumps are not running. The elevated storage tanks cannot be contaminated by ground water should a crack develop in the tank, but can be contaminated by other means. Both elevated and ground storage tanks may be contaminated by overflows and vent pipes not being properly screened, hatches not being secured and locked properly, improper cleaning, painting, and maintenance to interior and exterior tank surfaces. To prevent contamination a backflow device is available to install in the overflow line to prevent vandals from pumping contaminates into the storage tank.
The tank site locations should be secured by proper fencing to prevent children and vandals from easy access, and have regular inspections by utility staff for damage. Fencing should be cleared of any vegetation growth to make the site more visible. If electric service is available in the area, some lighting may also be a good deterrent for vandals. These sites should have "NO TRESPASSING" signs clearly posted and be visible from all directions to the tank site. A good Neighborhood Watch Program may very well be one of the most economical, and first line security measures you may want to implement. Storage tank ladders that are attached to the tanks need to be maintained, and not easy accessible to intruders. Ladder guards are available to cover a portion of the ladder to prevent intruders from easily climbing the ladder, but can be unlocked for water utility staff. No other ladders or means of climbing the storage tank should be left at the tank site.
Water storage tanks in the distribution system may have onsite level indicators engineered in their design, and / or have telemetry such as a dedicated telephone line, or a radio read transmitter, that sends tank level indications to another location, such as a water treatment plant. In case of equipment failures a pressure gauge located at the base of the storage tank is a very economical and effective onsite backup system. For example let’s say our telemetry for a ground storage tank is out of service, and we have no onsite level indicator, how do we determine the level of water in the tank with a pressure gauge?
1. Known facts:
·
the ground storage tank is a 40 foot tall tank
· the pressure gauge at the base of the tank reads 12 psi, (pounds per square inch)
2. What is the level of water in this tank?
·
Formula: pounds /sq in. x 2.31 = feet of water
· 12 x 2.31 = 27.72 feet
When determining tank levels with a pressure gauge we must be careful that if the pressure gauge is located above or below the base of the tank or if this is an elevated storage tank that we will not get accurate levels without further calculations.
It is very important to sample water storage tanks and check for free available chlorine residuals if chlorine is fed, turbidity, and perform bacteriological testing. Storage tanks of poor flow design or that may have been oversized for the area they serve, or during very hot summer temperatures may become stagnant. The stagnant water problems may be corrected by safely rotating the water levels in the tank while maintaining system pressure and adequate fire flows. The storage tanks in your distribution system should be inspected regularly from a standpoint of public health, security, safety, and preventive maintenance. Exceptional water quality entering our distribution system will only remain exceptional if we maintain our water storage tanks and distribution system. S
Updated 11/20/2006