Welcome to Summer

Today is the first official day of Summer, also known as the Summer Solstice. It is the day with the longest time period from sunup until sundown in the northern hemisphere. Because of this, June 21 is sometimes known as the longest day, but that can’t be correct, since every day is only 24 hours long!
Today’s solstice may seem longer than most, since it is on a Monday, and everyone “knows” that’s the longest day of the week.
We should also not confuse the solstice with the epic 1962 film “The Longest Day” that chronicled the story of D-Day, starring John Wayne, Richard Burton, Henry Fonda, Sean Connery, Roddy McDowell, Red Buttons, and a cast of thousands.
Starting today, the length of daylight will begin its slow decline until we reach the Winter Solstice on December 21, at which time the length of daylight will begin to grow once again. But the warmest days of the year are in the next 13 weeks — the Summer.
To water system operators, Summer is usually our most challenging time of year. This is because our customers use far more water during July and August than during any other time of the year. I might drink more tap water during these months, but drinking is a trivial use — at least by quantity. I might actually do less laundry and dish washing! So what is the source of the extra water demand?
It’s mostly landscaping. So now is a great time to check your home sprinkler system to make sure the heads are all functioning properly and pointed in the correct direction. It’s also a good time to change your sprinkler timers, if you have an automatic system. And it’s important to convey this same message to all of our customers. Saving water on landscaping can significantly reduce the maximum demand on our water systems.
A common problem with peak demands like our typical July and August flows is that treatment plants are pushed to the limits of their official ratings. If your system encounters this, now is a good time to have a discussion with your local regulatory folks — the Department of Public Health here in California — to determine mutually under what circumstances you could be allowed to exceed the maximum rating of your plant.
Note that most plants are capable of effectively treating water at flow rates beyond their “official” rating. This is because the official rating usually assumes that your plant has one filter out of service for backwashing. Most of us do need to backwash our filters every day, but that is not a 24-hour operation — it’s usually only about one-half hour per filter.
Let’s look at a plant with four filters. If each filter is washed once daily, the backwashing could be completed in two hours. The official plant rating essentially assumes that this will take 24 hours. Operating with four filters instead of three raises the capacity of the plant by 33%. If we can raise the plant capacity by this amount for 22 out of 24 hours, this plant could produce 30% more water — without exceeding the official filtration rate! This is a great place to begin your discussion with the Health Department, and a great way to safely generate that additional flow that you may need in the weeks following the Summer Solstice.

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