Clean water is one of the most basic human needs. Those of us who live in urban areas usually we get our water from a kind of central public system. Operation of the water system is a major responsibility that has public health implications safety. In dense urban areas, clean and abundant water supply is an absolute necessity, Not only for drinking, but also for sanitation and firefighting. And this is not just something we all need often. Water is both a constant necessity. Day and night, on weekends, holidays, and anytime between them. Therefore, the function of finding enough water, which makes it safe to use, then reliable distribution To order clients with almost no downtime is a huge task that requires Lots of infrastructure.
Perhaps the most obvious component of a public water system is high storage Reservoir, also known as a water tower. I am Grady and this is Public Works, my video series on Infrastructure and Humanity The world around us. [This video is curated by Bombas. More on that later.] Let’s say that you are the owner of a water system audience. You have found a source of water enough for your customers, you have found Way to clean this water so it is safe for them to use, now it’s time to send Water is on his way.
There are some ways we can get water from one place to another. One of them is just carrying it there. Whether it’s an animal backpack, a truck, or a bottle in your backpack, we are She still holds water physically all the time. But it is usually not the most efficient way. The first water infrastructure was to move the open canal. Whether in a trench, channel, or channel, water is transported by gravity, and sometimes it ends Very long distances. We still use open channels to transport water for irrigation and drainage, but they do have Some disadvantages as well. Water is exposed to pollution and pollution, channels that divide the earth, making it difficult For transit. Since the water can only flow to less elevated areas in terms of It started.
The latter is a major drawback, especially if you are trying to get water to An area with hills or mountains. So most public water systems today rely on pipes for distribution. Simply placing the top on an open channel allows us to take advantage of the pressure to move the fluid Where do we want them to go. Just like the electrons in the wire flow from the top to the low voltage, the liquid will flow into the tubes From high to low pressure. Therefore, if you raise the pressure at one end of the tube, you can send your clean water anywhere Want to go. How to raise the water pressure? With a pump.
The pump is a fluid-moving device. In some cases, the pump literally raises the liquid to a higher height, but in most cases A pump adds energy to the liquid by raising its pressure. And pumps, especially the size of pumps that serve entire cities, are expensive. So if you are charged with the task of choosing the pump size you need for your public water System, what to do? Perhaps you can measure the amount of water that the city uses on a particular day and choose The pump can match the flow rate. Let’s see how that will work.
It’s midnight in your city and most of your city the water customers are sleeping. Besides industrial customers running 24/7, the water demands are minimal, and The pump has no problem meeting it. But around 5 am, the automatic spray systems start kicking. Around 6 am, people start waking up and waking up, brushing their teeth, cooking breakfast, All the things that require water. It does not take long before water demand exceeds the capacity of your pump. Almost right off the bat, the new pump couldn’t meet the demand on your system, because it was just Average size. The demand for water in large urban areas can vary greatly over a natural orbit. Today, with peak hourly demand (usually in the morning or evening) sometimes 5 times the average daily demand. Therefore, if you are trying to meet your customer only needs water with pumps, instead of only water One, you may need up to five pumps (or one huge pump that can do a job 5). And not only that, you have to be constantly rotating pumps on and off to meet the variable Demand, increased wear and tear on retro.
Here comes storage. Let’s add a water tower to the system. Try this experience again. It’s midnight and demand is low, but you have the pump running wide open. Instead of flowing water to customers, it’s flowing into your water tower, filling Tank slowly but surely. As morning comes, demand begins to increase, your pump is still running. It is not able to meet the demand for own, but the water stored in the tank is making Difference arrives. All your customers get the water they need. When people start their day, demand drops again below average. However, the pump continues to run and the additional flow goes to the tank. Demand again begins to rise as residents of the city start cooking dinner, showering, Watering the plants. All this overuse of water drains the tank again before most people go to bed and cycle Starts again.
It is very easy to know how storage your water system works more efficiently. They grace the peaks and valleys of water demand not only on your pumps but all your Upstream infrastructure, including your own water treatment plant and raw water supply. Without storage, all of these facilities would need to
be sized for peak demand and increased Its cost. With enough storage, pumps and other infrastructure the size can be intermediate requirements and no saving Cost only, but also complexity, because you do not have to predict changes in demand And respond accordingly. Sometimes these peaks and valleys are predictable, but sometimes they are not. Some of the largest demand for water in urban areas are from fires.
Without the firefighting force and enough water to supply them, fires can catch out of control In dense urban areas. In fact, many of the most bloody disasters in history were pre-modern city fires Water systems. Now most municipalities and building codes have a minimum number of requirements Water that must be available to firefighters. Having stored water and ready, as in the water tower, goes a long way to being able To respond to an emergency. You might think, come on Grady. This is nothing new. Storage is the old solution to any situation where supply does not match demand. And, yes, it might not be a great thing to store water in a large tank. But the water towers are not just big tanks, they’re big tanks above the ground. This is because water towers are not just so water storage. They also store energy.
Water distribution systems rely on pressure to get water where it is going. If you’ve ever taken a shower with low pressure water, you know how frustrating it can be Be, because you can’t get enough water from the tap. Pressure on the water system is also important for general health. Without adequate pressure in the tubes, pollutants can make their way into the system through Small faucets or leaks. Most water systems get pressure from the pumps, and it takes a lot of energy to maintain them This pressure. Therefore, having the ability to store is not only the water itself, but also the energy that it has It was transported to it by pumps. In some areas, where electricity costs vary upon request, you can operate pumps at A night when electricity is cheap to fill your water tower. After that, leave the pumps turned off during the day. Electricity is more expensive at that time.
The tower to press the system and serve your customers. Energy in this way is also stored more widely to help with electricity Network reliability, but that’s a topic for another video. High storage is also useful during a power outage, by maintaining a compact system Even when the pumps are out of service. But how high are they? You may know that the pressure inside the body is related from water to depth. The deeper you go, the more pressure. Just like in a pool or ocean, the water distribution system has the same relationship Between depth and pressure. It only happens to be confined within the pipe chain. So, you can imagine the water circulation system as a virtual ocean in which we all live, The water surface in the elevated storage tanks represents a virtual surface Ocean.
Imagining the water system this way makes it easy to see the challenge of providing water For customers at the appropriate pressure. If our cities were flat, it would be pretty simple. All buildings will sit in the same depth in the virtual ocean. But most regions have at least some amount of topographic relief. Customers at low altitudes are at the bottom around the default, where pressure can To be very high. You might think this is a good thing, but plumbing pipes and hardware are only rated For some pressure, exceeding those ratings can cause serious damage. Sometimes buildings at low elevations will be equipped with special valves to reduce Pressure. Customers in the heights near the hotel will have a virtual ocean surface, very presence Low water pressure. As I mentioned, this can not only be frustrating, but also lead to system pollution. To solve this challenge, many large cities maintain separate distribution systems called Pressure areas, each with their own water tower, to serve customers at various heights Inside the city. However, what happens if you need customer service at different heights in the same location? High-rise buildings, such as skyscrapers, can have enough water pressure on the lower floors, While the upper floors can rise near the roof or even above the virtual ocean at Water distribution system. So, instead of relying on city water pressure, most tall buildings use their pumps Providing water to the upper floors. And some cities, such as New York, even require each building to have its own high storage tank.
Not every city uses water towers. Some have full water supplies at the highest altitude, reducing the need to add pressure To the system. Sometimes it makes more sense to rely on pumps alone to keep the system up And jogging. After all, water towers are not cheap, they take up too much space, and they can Allow the water to stagnate if not circulated enough. However, with a general water supply, reliability is the key. It has been a long time since gravity currently knocked out from a thunderstorm, therefore High storage tanks (fashion or fashion) are definitely here to stay.