The municipally-owned Milton Regional Sewer Authority (MRSA) serves many residential customers in Northumberland, Pa. It also treats...
According to the Department of Water Resources, California is facing the most significant water crisis in its history. In 2008, after experiencing two years of drought and the driest spring in recorded history, water reserves are desperately low. As a result of the drought declaration by Governor Arnold Schwarzenegger, many Californians will soon likely face mandatory conservation orders. In fact, many water districts and cities have already asked for voluntary measures.
Large regional water companies, like California American Water Co., which services the central coast of California, have already invested in high-performance flow measurement instrumentation to better understand their usage. Most Americans receive water service from community water and wastewater utilities. It is less known that private water companies own nearly 16% of the nation’s community water systems. However, countless smaller independent water companies, which fill the needs of populations in areas where large regional water providers do not have service, are rapidly realizing that an investment in the flow instrumentation pays off big time.
Carmel Riviera Mutual Water Co. (Carmel Riviera) operates independently from California American Water Co. and the Monterey Water Board, and is keenly aware of California’s precarious watershed and call for conservation.
Carmel Riviera, which serves up to 600 residents living along California’s breathtakingly beautiful and rugged Big Sur Coast, made the choice to upgrade to high-performance flow measurement instrumentation to understand exactly where their water was going.
Wayne Daniel, head of operations for the water company, knew it was time to improve their water measurement to improve the efficiency of the overall operation.
“This was an important step to drive water conservation by understanding our water-loss percentage, improving production efficiency and water quality by reducing backflush, and more accurately identifying over-users.”
Like most independent water companies, Carmel Riviera contracts the operation of their production facilities to a third-party expert. Carmel Riviera draws water from eight operational wells and the nearby Mal Paso Creek and has long relied on the expertise of Carmel Lahaina Utility Services, Inc. of Carmel Valley, Calif., to assure that their drinking water is always clean and available.
Tight Budgets, Conservation Investments Difficult
Independent water companies are typically run on a very tight budget and do not always have the funds to invest in upgrading their facilities with the latest and greatest instrumentation. With its ozonation system, using ozone as an oxidant in the treatment process, and SCADA operating system, Carmel Riviera is on the cutting edge of water treatment for an independent, grade-2 water company.
Daniel had always suspected that non-revenue water loss in their distribution system could be up to 100,000 gal per month. He decided it was time to finally discover how much water was really missing. For years, Carmel Riviera relied on water readings taken from antiquated, worn-out mechanical paddle-wheel flowmeters that simply couldn’t be trusted.
Eric Furtado, the lead water operator from Carmel Laheina, knows all too well the limitations of poor flow measurement instrumentation. “There is no sense collecting data that is inaccurate,” Furtado said. “With the previous meters, I would have to write something down that I knew was not very accurate.”
In fall 2008, Carmel Riviera upgraded their water treatment plant with three of Sierra’s Innova-Sonic Model 205 transit-time ultrasonic flowmeters .
Installation and Use of the Clamp-On Style Meters Are Painless
Today’s advanced ultrasonic flowmeters are a solid choice for water flow measurement. Not only are ultrasonic flowmeters extremely accurate, but they also have no moving parts that wear out or plug up. Installation is where real savings occur. Instead of shutting down the process and busting open a large pipe to install the meters, simply “clamp-on” two sensors on the outside of the pipe, punch in menu-driven settings and begin to take water flow readings.
What Wayne Daniel appreciates most is the versatility of Sierra’s meters with their ability to clamp on to any size of pipe made from a variety of materials from galvanized steel to cast iron to PVC. For a small, independent water company with limited resources, being able to use just one meter to measure water readings from many different pipe sizes in the water treatment plant becomes a substantial cost saver.
“Two pipe clamps and you’re done. It’s a much less invasive installation. You can detach the readout from the cable, move anything anywhere you want to move it. You can unplug them and you won’t lose all your data. With Sierra, the sensor is external to the pipe, so regardless of what is running through the pipe, it is not going to affect our ability to read what is in the pipe,” Furtado said.
How Do Ultrasonic Meters Actually Measure Flow?
An ultrasonic signal is transmitted in the direction of the flowing fluid (downstream), and then another signal is transmitted against the flowing fluid (upstream). The time for the sonic pulse to travel downstream is compared to the time for the pulse to travel upstream. This differential time is then used to calculate the velocity of the flowing fluid. Sierra’s Innova-Sonic Model 205 allows operators to test signal strength, quickly verifying that the meter is indeed working, a welcome change to breaking pipes. Gone are the days of shutting the water supply to their customers, losing countless dollars in lost water service revenue, and breaking different size pipes to install mechanical paddle wheels. With a slightly higher initial investment, Sierra’s meters pay for themselves with versatility and lower installation and maintenance costs.
Investment Pays Off: Finding Mystery Water
With the flowmeter upgrade complete, water readings were finally trusted. Eric Furtado discovered mystery water loss almost immediately. In the filtration stage of water treatment, raw water is pumped through a 4-in. pipe and filtered through a garnet red sand media that captures any particles that are not water or water soluble. When these particles on the red sand media begin to build up and clog the system, the pressure outside the inlet valve increases, triggering a backwash cycle, a reversal of flow that lifts the red sand media and cleans the particles that have built up over time.
Improved Water Quality
During a routine check of the meter readings during a backwash cycle, Furtado noticed that both the backwash meter and the production meter were registering.
With this new, trusted data, he discovered that they were not only recording false water production, but 500 gal of backwash water was entering the finished water supply. They also verified that each backwash cycle uses about 4,500 gal of water.
“I feel good now that I have three meters that are reading right. It has reinforced what I thought was happening, but couldn’t confirm it because the meters I had before I didn’t trust. Now my math is correct,” Furtado said.
Furtado explained that with this accurate data they should be able to add the amount of backwash water used to the amount of water the customer is using to give a rough idea of water production in a given 30-day period. That is the goal. “We don’t want any mystery loss,” Furtado said.
Carmel Riviera’s water management system now gives them accurate and precise water production readings so they can now accurately calculate water-loss rates. Sierra’s ultrasonic meters are “pretty amazing and fairly simple to install and operate. I can’t recommend them higher,” Daniel said.
Historically, Carmel Riviera Mutual Water Co. estimated its annual water loss rate through leaks, waste, evaporation and other losses at around 30% of the total produced. The company budgeted almost $60,000 per year in initiatives to reduce these leaks, including labor and materials for surveys and expensive repairs. After six months of using the Sierra Innova-Sonic ultrasonic flowmeter, they found their actual loss rate to be only 12% of their production. The improved production and usage figures derived from the Innova-Sonic enabled the company to significantly reduce their annual maintenance and operations budget to target more funding on improving conservation and efficiency.