Transcript for:
Overview of Water Distribution Systems

Hello everyone, welcome to the water distribution prep class grades one through three. During this, you know, 40 minutes time slot I'm going to try to cover range of knowledge for system layout, valves, meters, hydrants and backflows. So we'll get rolling here.

Before we want to get into the range of knowledge stuff, I want to just kind of, you know, give you guys some study tactics. This is all stuff I pulled off AWWA. And even, you know, looking through it, stuff I've done through the years, just kind of, you know, set the mood, finding an area, place to concentrate, you know, creating that environment that supports it, you know, studying to understand, you know, try not to memorize, you know, because this is all stuff you're going to use in your day-to-day, you know, work life, you know, write what you read, summarize material in your own words, you know, make flashcards, find a way that, you know, you'll be able to retain the knowledge that you're studying.

A couple more. ideas is you know don't procrastinate um i'm guilty of it i'm sure you know my treatment i've been outside the testing facility you know early that morning cramming on what everything i should have done from the weeks past and it made my life a lot tougher than i needed to be it looks like there's a couple questions is it uh anything can everybody hear me all right can i be moved to the other room for the wastewater please yeah But, Corey, there's about three people in the chat that need to be moved to wastewater. Okay.

I am having a little trouble finding out how to do that, so I apologize. It should be easy, but it is apparently not. Let me see here. Okay. I am.

going to and who's at let me uh all right i think i figured out the way i figured it i find i'm there wait a minute uh michael logged out so who just asked to be moved there's a couple of people in the chat why don't you uh if you could just take that and then uh and then danny you could probably just keep going and hopefully get those folks moved to wastewater Yeah, I'd like to be moved over to wastewater, please. I'm sorry. I was muted. And who is that?

Joseph Shohan. Joe, I'm sorry. I don't see you here.

Could you text me in the chat field? Sorry about that, Pete. Good to go.

But you know, in a couple minutes, if you don't get moved over, please raise your hand, let us know, and we'll make sure we work on getting you guys moved over. Till then, you're going to learn a little bit about water distribution. So sorry, but hopefully we can move it over quickly.

And these, the things I'm talking about, study taxes, they work no matter where you are, what tests you're taking. So obviously don't procrastinate where I just was. And we're all, you know, guilty of it.

Something I've kind of done more as I've gotten higher in my distribution certs, in which I currently hold my grade five, is kind of been quality over quantity, you know, heavy, you know, with busy work life, busy home life. two kids, sports, everything going on, trying to grab those short intervals, the 15 to 20 minutes, the stuff that's easy to grab, you know, the stuff at lunchtime, you know, stuff at the end of your day before you go to bed, and just kind of picking up those times to taking a break, going through it, and getting a little more study material in, and then setting your goals high, you know, shoot for, you know, shoot for that 100%, you know, don't shoot for that, I just want to pass the test, we all just want to pass the test, I totally understand, but. you know, set your studying up and shoot your goals high, because it's really hard to get 100% on one of these tests, and I would congratulate anybody that does. I think if you get a 90%, that's awesome.

So, you know, set your goals high, that way you can assure yourself that you're going to pass. And lastly, something that I did through my entire career is I kept going. The best way to retain the knowledge for these tests is to continue to use it. Get the next cert you can get as soon as you can. Just keep going.

That's like probably the biggest... you know piece that if you can leave today with is continue on your education continue to get certs Moving on to some resources. I heard some questions earlier about books, resources to use.

The other things what you're going to see today are right out of the water distribution operator book from AWWA. I've utilized the certification exam prep books in the past, especially for math. These work for me. And also the water program, Sacramento State, a wealth of information, tons in there. Just remember to grab it at small bits.

Those books are huge. So those are some definitely some resources you guys can use. through all your certification tests. Some of the stuff that's new that I wish I had a chance to utilize are some of the apps available.

And looking towards, I'm looking forward to taking my treatment three years soon. These are definitely something that I'm going to be testing out. So hopefully this next time around, I can give you some of my, you know, experience with these apps.

I think they're, you know, having some on your phone will definitely help with those 15 to 20 minutes study sessions. And then another training resources, I've used them in past, WaterWise Pro. They also have an app.

They do in-house trainings. They've been helpful on my journey, on my certification. So definitely throw it out to them.

And then I also heard, I just kind of added this. I apologize. I would have thrown a link. But I heard just some questions come up in that meeting.

And I wanted to throw the California State Water Board. I apologize. It's not a link. I did it real, real fast just before this started. Use this.

This will tell you everything, your range of knowledge, you know, all those questions that came up. They have all this stuff written down in there. This is also recorded.

So you'll be able to get on Bayworks website, but go to your California State Water Board. It helps you, you know, with all the questions we went over and it really helped you get prepped for your exam. So sorry.

Sorry, it's not a link, but it's thrown in there. All right. Now we're going to get rolling into some of the study questions, some of the stuff going on in your exam.

First is, you know, what is a public water system? You're going to see this question. So there's three types of public water systems. There's your community public water system.

It's 15 or more service connections or serves 25 more persons for more than 60 days a year. These are your municipal systems, your rural water systems, mobile parks. These are your communities.

You have the non-transient, non-community. Serves an average of 25 people who do not live at the location. But the same people use the water for more than six months per year.

These are your schools, factories. Then you have your transient non-community public water system. Serves an average of 25 persons per day, but only occasionally and for short periods of time.

And this is these are how you're probably going to see them on the test too. So community public water system, non-transient non-community, and then your transient non-community public water systems. Alright, then we'll go on to water distribution system layouts. Three general ways in which the distribution systems are laid out. You have arterial loop system, grid system, and tree system.

So your arterial loop system. So the arterial loop systems are designed to have a large diameter water main around the water surface area. That ensures that flow will be good at any point within the grid because the water can be supplied from four directions. Then you have your grid systems and grid systems have the most of the water mains interconnected and they are reinforced with larger arterial mains that feed the water to the area. So you have your main pipe down the center and then you have your feeds outside of it.

Then we go to tree system and tree systems have transmission mains that supply water into an area but the distribution mains that branch off are generally not connected and have many dead ends. This is usually considered poor design because flow to many locations is just through one pipe. And I know you're probably thinking about your system and it really ends up being a little bit of everything. You know, none of our cities are squares or, you know, parts of your distribution systems or zones end up being trees.

So, you know, this is just how you'll see it in the test of how they design systems. And we'll move on to water system valves. So valves in the water distribution system serve many different purposes and functions, and many types of valves are used for special purposes. Valves most often found in water distribution are gate valves, butterfly valves, check valves, and control valves.

Some specialized valves found in the distribution system are pressure reducing valves, pressure air relief valves, altitude valves, air reliefs, and vacuum relief valves, and then valves, you know, general is you want to exercise your valves open and fully closed at least minimally once every two years. So dive into gate valves. So gate valves are used use a restricting disc. that is lowered into a seat to stop flow.

Gate valves are designed to start or stop flow. They should not be used for throttling flows for long periods of time. Different types of gate valves, you have the rising stem gate valve, also known as your OS&Y, it's an outside screw and yoke. They have an extended screw extending above the bonnet. These types of valves are used at well sites or pump stations.

It's very easy to identify whether the valve is open or closed. Non-rising stem gate valves are used in underground applications on water mains and hydrant laterals. And then a test question that I can guarantee you is a question from at least D3 up through D5 is a bypass valve. If a large valve, you know, say you have a water main you're doing a repair on, you know, like 18 inch main.

So this is where this bypass valve would come in. If a large valve has pressure only on one side of the gate, it may be almost impossible to open. bypass valves are used to let water into the unpressurized main to put pressure on both sides of the gates so the large valve may be operated. It's a test question.

I wish I had them in our system. I think everybody does. I haven't seen any yet, but you know, at least in the distribution, but you will see it on your test. Butterfly valves. So butterfly valves have a disc that is rotated on a shaft across the diameter of a pipe.

When in the open position, The disc is parallel with the flow and when closed it seals against a rubber or synthetic seat on the valve body or the disc. The butterfly valve is primarily used for on-off service. They can be used occasionally for throttling but prolonged throttling is not recommended.

Check valves. Check valves are designed to allow flow in only one direction. Most common use in water systems is on the discharge size of a pump to prevent backflow when a pump is shut down.

Also with a type of check valve is a foot valve and a foot valve is a special type of check valve that is installed at the bottom of a pump suction that prevents the pump from losing its prime. All right we'll roll on to pressure regulating and relief valves. So pressure reducing pressure-relating valves operate automatically to throttle flow and maintain a set pressure. Glow valves are the used for pressure reducing valves.

That type of valve is specific to those. Pressure relief valves are used to relieve high pressure from water hammer, failed PRV valves, closed valves, or other high pressure scenarios. The pressure valve come on in a set at a set pressure and the valve works automatically. A lot of times you're going to see pressure relief valves in the same area as your pressure reducing valve as they are you know they are your fail safe.

If your pressure reducing valve fail the pressure relief valve would kick on that set pressure and you know save your system from that high pressure. Also pressure reducing valves could come in small sizes sometimes you'll see them on your customer's service if you supply you know, higher pressure to an area, a lot of times you'll see the small one there in the center on your customer's side of the meter helping reduce the pressure and saving their appliances. All right, altitude valves. So an altitude valve is used to fill a reservoir and is controlled by pressure settings. The lower pressure setting allows the valve to open.

and fill up the reservoir and the high pressure setting closes the valve and stops the reservoir from filling. These, you know, basically your lower pressure set point would be, you know, the footage that you want that tank to start filling and the high pressure set point would be, you know, the footage that you want to stop filling. So say you wanted, you know, you want your valve to come on at five feet then you want it to turn off at 18 feet.

You can set that through that large pilot assembly with the springs. and that valve will operate automatically on those set points. And then do please feel free to, you know, stop me if you have any questions along through it. I know sometimes I can start to move quickly through it. Other valves to be aware of that you'll see you'll see on the test, air and vacuum relief valves.

Air reliefs allow air to vent from the main and the vacuum relief leaf allows, you know, if a vacuum occurs, they will emit air into the system. They're usually float operated valves, usually located at high points of the system. and then on the discharge size of pumps.

They'll come in a range of sizes too. I'm sure you've seen them on your discharges or even in distribution system. Your corporation stop is connected to the water main and the service line. It is the main shutoff valve located under the street.

So usually tapped right into the main, that's your isolation valve. You know when you're replacing a service that's about you're shutting off right there at the main. Your angle meter curb stop is connected to the service line and the meter. That's the valve located in your customer's meter box that you isolate to change out meters or you may be doing a curb stop change out on copper services. Water meters.

This is what I wanted to put in here because I will admit through my grade one through grade five I was never really strong on my water meter side of the tests and I wish I was always would have studied a little bit more when that test came up. So water meters are what generate the revenue necessary to sustain all aspects of the water utility. Water meters measure the flow that the customer use.

You know we use them at pump station pumps. We you know use them at our wells. You know we use them at our if you have turnouts where you're purchasing water from other retailers.

We're metering all that type of water. Advanced metering infrastructure. AMI is allowing for real-time data capturing from any meter in your system. It is changing the way we read meters and capture data for billing and water loss. Water meters should be tested for accuracy every 5 to 10 years and replaced every 15 to 20 years.

So meters, we start with positive displacement meters. And positive displacement meters are used to measure relatively low flow rates. They're most commonly found in sizes ranging from 5-8 to 2-inch. And you have two different types of positive displacements.

You have your mutating disc meter. And mutating disc meters measure using a tilted disc that rotates as the water flows through the meter. The rotation transmitted through the gear is to register.

And the register then reads in gallons, cubic feet, or... cubic meters. Then the other type of positive displacement is your piston type.

And on a piston type, the water flows into a changer and displaces a piston, and the circulating motion is transmitted to the register. The register then reads in gallons, cubic feet, or cubic meters. Continuing on meters, we have our velocity type. And velocity type meters measure the velocity of flow through a meter of known internal capacity. The speed of the flow can then be converted into a volume to flow a flow to determine the usage.

Different types of velocity types you have a multi-jet meter very accurate small sizes and commonly used in 5 8 to 2 inches. for residential and small commercial users. Multi-jet meters are used multiple ports surrounding an internal chamber to create multiple jets of water against an impeller. The impeller's rotation speed depends on the velocity of the water flow. Turbine meter, the turbine meter uses the flow direction is generally straight through the meter allowing for higher flow rates and less pressure loss than displacement type meters.

Turbine meters are generally available in 1.5 inch to 12 inch or higher pipe sizes. Then a compound meters and compound is used where high flow rates are necessary, but where at times there are also smaller rates of flow that need to be accurately measured. Compound meters have two measuring elements and a check valve to regulate the flow between them. Large meter is normally a turbine meter and the bypass meter is usually a positive displacement meter.

You'll see compounds at your fire services to a building or just to have your large meter to measure or any other type of industry where they don't use that high flow as much. They still can be used in small amounts of water. So making sure you're getting everything going through that system.

Continuing on meters, we have magnetic meters and ultrasonic meters. magnetic meters or you know we probably hear more called mag meters. You know water flows through a magnetic field in a small electric current that is proportional to velocities electronically converted to a flow rate. Then down into ultrasonic meters.

Ultrasonic waves transmit it upstream and downstream through a pipe wall and liquid flowing in the pipe. By measuring the difference in the travel time and knowing the pipe size, the meter determines the velocity and flow rate. And then they have a transit time ultrasonic flow meter.

It uses two transducers which mount to the outside of the pipe and function as both ultrasonic transmitters and receivers. The flow meters operate by ultrasonic. alternately transmitting and receiving a frequency modulated burst of sound energy between the two transducers. This is something like ultrasonic now we're seeing in our system on our residential water meters, very accurate, able to read extremely low flow that you know your your positive displacement meters your older meters would not even register. I know going through this process in our city you know water bills increased a little bit.

You know, you're always telling you, the customer always wants a brand new meter, but you're always telling them the new meters are much more accurate. So we're seeing a little bit of experience with this on our end. And I only see the metering and AMI systems coming through the entire Bay Area and really getting our accuracy levels extremely higher. All right, pressure differential meters.

Two types of pressure differential meters here. There's the Venturi meter. It operates on pressure differential.

The pressure at the throat and upstream are compared. The difference is converted into gallons or cubic feet. Then you have your orifice plate.

It's a plate with the circular holes installed in between flanges on a pipeline. And then you take pressure readings of pressure at the plate and upstream are compared and converted to flow. Some of your older pump stations, older technologies, a lot of this was still around before people started. converting over to mag meters.

And they work, just gotta keep them serviced and make sure the pilot's sun louis are clean and they definitely have their place, still do. All right, we'll roll on to fire hydrants. Fire hydrants inspect every year, install every 350 to 600 feet apart, must maintain a minimum of 20 PSI during flow tests.

Minimum setback from the curve is two feet and your velocity range. usually is, you know, half to three feet per second. Max is around five feet per second. Let's get the type of hydrants going here. First type, so, yep, anybody?

All right, is a dry barrel hydrant. Stuff we don't really see here on the west coast, we've got a lot of freezing, freezing areas, but dry barrel hydrants are used obviously in locations with freezing weather. They have a main valve and a small drain valve in the base.

that allows the barrels to drain when the main valve is closed. Advantage that to this type of hydrant is that there's no discharge of water when a fire hydrant is hit or broken. And then there are two different styles of a dry barrel.

There's a dry top shown to the right and a wet top. And the only difference between the one shown on the right and the wet top is that the threaded end of the operation mechanism is not sealed. So water would be around your, you know.

your stem nut there. It won't be sealed off like shown here. Wet barrel hydrants.

Wet barrel hydrants are filled with water all the time and not suitable for locations freezing weather. Each nozzle on the hydrant has a separate valve and the isolation valve for that hydrant is usually located in the street. So this is probably the hydrant most of you are familiar with.

You're probably familiar with the isolated street as well when those Hydrants get hit, hopefully it's just for hydrant maintenance, but you know when those hydrants get hit, usually it's right underneath the cascading water. Also, there's a hydrant color coding. This basically, you know, the painting the fire hydrants according to their capacity helps utilities and fire departments to permit the most effective hydrant for fighting fires. They paint the tops or caps to make them easily visible day or night, and they can be rated. by available flow to those hydrants or based on water main sizes.

Not something that I'm super familiar with here in Pleasanton, but it is, you know, kind of an unexpected range of knowledge. So basically they're just, you know, set up on either pressure given but mostly by the main size by the flow that you're able to get from those hydrants. So I imagine in areas where, you know, they have different pressure zones close together, this will be valuable. I think it was a question from Albert. Yeah, so we, in the city of Brisbane, we do the rings for pressure zones, but we don't do the...

uh you know six inch eight inch ten inch is that like a requirement that hydrants are painted that color is it just the recommendation yeah this was yeah i don't think it's a require requirement i'd have to double check this is something you know i pull from the book okay you know i think you guys are mostly doing it now you're painting it based off of your pressure zone or is it based off your fire flow that you can give it to give to them in that in that area uh it's it's based off of the fire flow but they're not the hydrants themselves aren't we just have reflective rings so that when fire comes up they can see based on the color right away in the night okay boom you know we go for it so okay thank you i just wanted to ask that okay yeah no i'm glad you brought that up because i was kind of curious you know and that's that's i'm glad to hear that it's out there so you you do you paint the rings of the valves and they are based off of probably the lower chart here i think the upper chart you know it's you know they'll correlate really closely. I mean, obviously, you know, you're, you're going to get much more flow out of your 12 inch main than your six, but it probably, you know, it just based off there's two options here, but it sounds like this lower chart is what people use. Yeah. So thank you for raising your hand and let us know.

That's great. Now, do you have pressure zones up close together or are they just, is it, is it, do you have pressure zones close together or is it just a standard for? Yes, they're very, it's, kind of stacked on top of each other. Brisbane is set up in a hill form, so it kind of goes one, two, three, and based on where the tanks are, there's two sections of Brisbane, a lower and a higher, and based on where the tanks are obviously and the size of the pipe, that's changing because there's a whole section from upper to lower that are operating on the same tanks, so that changes as it as it goes.

So that's, that's kind of, like I said, they're stacked on top of each other. So they are very close, close proximity. Awesome.

Thank you very much. Thank you. All right. Let's see here.

Let's get into, I kind of added this towards the end. I was originally just going to do, you know, stop there at hydrants, but I want to get a little more in there and see if I can get. As much as I can fit into this 40 minutes because it's, you know, it's never enough time to study for a test.

I want to give you as much of the range of knowledge as I can on here. So I'm going to roll into cross connection, cross connection and backflows. So we'll start with cross connection is a connection between a drinking or potable water system and an unapproved water supply.

The mixing may lead to contamination of the drinking water supply. So there's two scenarios of backflow. is the flow of any water, foreign liquids, gases, or other substances back into a potable water system. And there are two conditions that can cause backflow.

You have back pressure and back siphonage. Back pressure is a condition in which the foreign substance is forced into a water system because it is under higher pressure than the system pressure. And then back siphonage is a condition under which the water system pressure is less than atmospheric, you know, it's under a vacuum and the foreign substance is essentially sucked into a pool of water system. So say like we're talking there, you know, you have a water system on the hillside and you have a water main break towards the lower, that can almost create a back siphonage as that water is flowing through and going out of that, that water main break down below, it could possibly cause a back siphonage in your system. So just a little.

All right, and then we'll go into backflow devices. So the first is your air gap. And these are really, these are all going to be shown in the slides as from your, you know, best type of backflow device down to your worst. So your best is your air gap is a physical separation between potable and non-potable service.

They're used where there's a high, high risk for health hazard. The gap distance is two times the diameter of the inlet pipe. and no less than one inch and the most this is the most positive type of protection.

I know that we use this at some of our sewer systems where we we use water you know in our on our seals for our pumps we actually have an air gap and then we have a a pump system that takes care of those sewer stations. So obviously worst case scenario is having a connection between your sewer and your water so that's where an air gap would come into play. Backflow device also is we have a reduced pressure zone.

The reduced pressure zone RPZ device consists of two spring-loaded check valves with a pressure-regulated relief valve between them. If there is a potential for back siphonage situation, both check valves will close and the space between them is opened up to atmospheric pressure. So if there's a back pressure situation, both check valves will close. If the second check valve leaks by, it will escape through the center relief valve. And these are installed in situations where there's a high risk for health hazard.

Probably your next best compared to your air gap, or they are the next best. next best next compared to your air gap and they're safer than one or two check valves you know obviously not as positive in the air gap there again they must be installed where the relief ports cannot be submerged they protect from toxic substances as well and they need to be tested every year by a certified tester so these are obviously you know you don't want these in a in a pit situation where the pit could flood you can have an event and then have a chance of that water being sucked up through your relief valve and back into your system. So be mindful of that.

All right. Next backflow device is our double check valve. And a double check valve backflow preventer is designed similarly to an RPZ, except there is no relief valve between the checks.

The protection is not as positive as an RPZ because the possibility of the check valve is leaking, and they are not recommended for use in situations where health hazard may result from a valve failure. I just show a little bit of a schematic of what happens during reverse flow. And lastly is the vacuum breaker. So two types of vacuum breakers.

There's the atmospheric vacuum breaker, also called an anti-siphon valve. They're designed to be used on connections where there's no back pressure. They're designed for intermittent use, typically used for irrigation systems, and they have very low protection. And then there's your pressure vacuum breaker. It is similar, but it's designed for it to be used under pressure for long periods of time.

should never be used again with the possibility of back pressure. And this one must be installed 12 inches above the highest fixture on discharge piping and very low pressure, very low protection again. Again, seen on your irrigation systems.

All right, I think that's really wrapping it up here. Probably moved it through a little bit quicker than I planned to. I know I just talked with one of my operators who was doing a distribution three test.

He didn't want me to let you guys know. He did see some more questions on pumps, pump maintenance, you know, packing land, stuff like that, that he wasn't really prepped for. So I just wanted to, you know, I'll try to, I was going to add a page to this and kind of keep it living.

And obviously. I can probably do a couple more slides. I tend to move a little bit quicker, but I try to give you guys as much information during these prep classes as possible, but I'll also be holding, I'll be putting on there stuff that as I talk to operators or even you guys, as you guys start taking your tests, you know, shoot Bayworks over, shoot me over what you're seeing on it. I like to make this kind of a living document so that we can help each other get through these tests and then, you know, just help the next guy. So again, like I'll be doing my T3s.

So my next My next go around, I'll have a little more experience with those apps. I'm sure they'll be valuable. Looks like we got a hand up, Devin. Yeah, I was wondering if they ask you on the test, what's the best cross connection device? The air gap would be the correct answer, probably.

Your air gap is, yeah, your air gap. I kind of did it in order. So your air gap is your most positive, you know, protection. Okay.

And everything. Everything you're seeing in these slides is out of the AWWA book. I use that AWWA book distribution working book for all my tests.

But yeah, this is your, it's kind of in order. Your air gap, your RPZ, we call it the RP device, but they throw it as our reduced pressure zone in the book. And I want to make sure that's what you guys are seeing on the test. Yeah, because in some books you study, they say that RPZ is the most effective and then some say the air gap.

So it's like. I just wanted to kind of make sure which one's the one that probably the correct answer on the test. Yeah, this, you know, you got to look at to make sure they're not asking for like actual backflow device, which I don't think they're going to trick you on. I mean, this is straight from the book saying this is the most positive type of protection.

Now, if they're asking their question and they're going to say, Hey, you have an RPZ. Usually they line them out and they like, I've seen the test questions as they line them out as like four different options and it says, pick the one that has, it goes from greatest to least amount of effectiveness. And they'll throw like air gap, RPZ, you know, double check, single check, you know, vacuum breaker.

And then the next one will be RPZ, you know, double, double check air gap. They. I've seen those questions in the test. They usually line out all four, and they ask you which one is either the least or the most effective, you know, in order. So, you know, if you're taking the test, especially in the math, you know, they throw little things out to try to, you know, trick you.

So make sure you take the time to read those questions thoroughly because you'll be like, oh, I got it. And then you may have missed it because it said least effective or most effective. So I've seen it that format in the past.

All right. And also, Benjamin Connolly, Danny asked, will type of piping, concrete, iron, etc. be a big thing on the test? I would imagine so.

I probably could have thrown someone on here. You're going to see, yeah, on the website, they give you a full range of knowledge. But if you look at it, it's really overwhelming because it says you need to learn.

You need to know 20% of distribution and 20% of treatment. So that's always tough. You're definitely going to want to know your types of pipe and, you know, the types of pipe, your, oh, there's smoothness factor, which I know what it is, your C factor. Now I'm drawing a blank on it.

I want to say C factor. Somebody can help me out. But yeah, your smoothness factor, your pipe, you know, the types of pipe, those will be on there.

In water distribution, you need to know your aquifers and wells. I know that threw me for the loop in my first D1 test that I went to. Like situation use?

What's that? Benjamin just said like situation use. I don't know if that's connected to anything.

You know, I don't know if they're going to I'm not I don't remember them asking for like situational use as far as like soils. that I can remember, but just mostly types of pipe. I think you just, they want to see you're familiar with types and then maybe the strength of it. But I don't think, I don't remember seeing any situation. I don't know if anybody in here in class can help out with that one, but I don't remember situational, but definitely the types and maybe, you know, why maybe you would choose one over the other.

Yeah, I'm getting the questions are coming fast and curious. Oh, I can't even see them. All right.

I mentioned that I've had a couple questions about this presentation. Excuse me. The video and the presentations. Sorry, guys.

This is my frog in the throat time of day. COVID. I don't know why, but anyway.

It happens every day this time. Everything will be posted to our BayWork website, baywork.org, the videos and the presentations. And I'll send out a general email to everybody when the links are up and active.

So I hope that answers that question. We'll also be posting a survey question at the end of this class, and also we'll be sending it out via email. It's only a couple questions.

really appreciate your response to those. Now back to the questions. Jonathan Gong says, how is the reduced pressure principle related to the other backflow devices?

Related, so, you know, this is, it's basically, it's still a double check. It's basically, you know, but with the, it has the relief valve between them. So with your double check, You know, if one check fails, the other check will hopefully catch it.

But if both, you know, both checks fail, it won't. And you're in the, the RPZ is just like the next step to where, I know it's kind of hard in these slides. I was trying to find a better one.

But, you know, if there's zero pressure coming in on your, you know, say there's back siphonage going on, that really air relief will open up. If your number two is obstructed, it will go out of the relief. You know, so if your second check doesn't doesn't close, it relieves it.

So it's just it's an added layer of protection. over the double check, whereas you have your relief valve and not just two check valves. And this may be out of line because this is a subject I'm not familiar with, but both John Pedley and Gil Revis, John said yes, C-factor, and Gil said C-value.

I don't know what that is. Yeah, if you really feel that, I can definitely add this in for future. if water main pipe is. But like I said, yeah the C value or factor, that's the smoothest of the pipe interior. There's definitely gonna be questions on that.

I, yeah, like I said, I can't remember any type. Just knowing the different types of pipe materials is really, you know, the big. There's gonna be probably connections, you know, flange connections come, you know, bell and spigot, that type of stuff that you're going to need to know on, know as well on there. Great.

And I don't know if you can answer this one, but for the AWWA study book, can we purchase that on their website? Yes, on AWWA. Yes. Yeah.

So, you know, I mean, this is that's my water distribution operator with all of my little note sections in there. The if your system, I imagine they have a membership through their system. Sometimes it's held through different people in your organization. The you know, that's.

they can go through they get a much better discount you know as a membership but you can't be purchased through their website and like I showed earlier they they do offer apps now so that's just another option so it's just something to think about too. Danny says considering this presentation is for grades one through three how much of this content is on D1? This is probably a pretty basic. I try to kind of grasp all of them because really your D1 through 3, a lot of your regulation stuff gets a little more intense. A lot of the basic information I'm showing you in here is stuff I would, you know, I recommend you know for that D1.

I don't think I got too crazy. I'm not, you know, showing any math. I think this is really basic information.

It's kind of why I chose each one of them that you're going to see. on all the tests, I would say from D1 to D3. Great.

I am going to post the presentation. I posted it a little bit earlier, but I'm going to bring it up again, she says hopefully, and get to that. And then I'm also going to share with you the questionnaire as well. But you can also ask more questions as I'm hunting and pecking for all this great information.

Yeah. And then also, just please let me know. Like, I picked out general areas that I thought would be helpful for you.

Like I said, I picked stuff that you're going to see in all, I felt, through one through three. If there's any other areas that you guys would like to see on something like this, this, you know, obviously I have, I have 40 minutes, which is, it's impossible to go through the whole test in it. But if there's another area, definitely please let me know.

I would like to, you know, like this is for you guys. This is for my crew. You know, my guys are still continuing. My crew is still going through and getting their certifications and I want to use this to help them out as well.

So please, you know, feel free. Let me know what you'd like to add. And I will definitely try to add it through there. I know.

I can go quicker through it, but it's mostly like, I think the most value is you guys coming back to this and being able to use it, you know, after the fact as well, rather than having somebody, somebody talk at you the whole time.