Did you know that you can connect your existing SCADA system to FlowWorks? Why would you want to do this? The first reaction that many people have is “we already have a SCADA system, why would we want to use FlowWorks?” Because FlowWorks is not just for dataloggers, and it does a lot more than just store and plot data. Think of some of the things you could be doing with your SCADA data if you used FlowWorks to do it…

If you are in the municipal business, odds are that you have a SCADA system. You probably also have some dataloggers and maybe some sewer flow meters. Wouldn’t it be nice to put all of that data into one place? Do you want to easily plot flow data from your treatment plant SCADA with rainfall data collected by your dataloggers? How about adding some laboratory measurement results along side? If you use FlowWorks, you can do this.

Plus, if you want, the data flow can go BACKWARDS from FlowWorks to your SCADA! What if you use FlowWorks to collect rainfall from some rain gauge dataloggers, but your SCADA also collects rainfall data? The two can give data to each other, so you and your users see the complete dataset! Core staff who use SCADA see valuable information, using the interface that they are used to. At the same time, data from SCADA (which is often difficult to distribute to users outside of the SCADA system) is made available to a larger set of users. No more having to deal with different data formats because some of your data came from the SCADA, some came datalogger brand X and yet other info came from Brand Y.

Setup Personal Alarms

Use the FlowWorks alarming system to setup notifications for other purposes that aren’t mission critical SCADA alarms…maybe you need to know when flows at a treatment plant reach a certain point so you can take a sample…or it’s time to photograph potential flooding at a drainage location…or maybe you want to know the next time a chlorine analyzer shows a low value so that you can go and take a sample to verify it. These are all things that you can do but might not have SCADA alarms setup for…with FlowWorks you can create your OWN notifications without requiring your SCADA staff to setup these alarms for you.

Your OWN Notifications

Yes, that’s what I said – this is a big deal.  In FlowWorks, each user can customize their alarms and notifications, independent of anyone else.  This can help you do your job more efficiently, the way you want to do it, and without extra corporate overhead that is so often required.

Custom Reporting

Use the reporting functions to produce tables for your reports…total water consumption, water quality reporting, rainfall summaries and statistics, pump run times, chemical injection summaries…if your SCADA system has been measuring it there is something that FlowWorks can do to make it more useful to you. Why record it if you can’t use it for anything?

SCADA Data Security and FlowWorks

FlowWorks provides data viewing and analysis tools only.  There are no control functions that would be in a typical SCADA setup.  This means that when you are viewing data sent to FlowWorks from your SCADA system, it is a mirrored COPY of the data rather than the original data itself.  In this way the finite control details of your system are protected from the user, leaving your system and network ultimately secure.

Do you have information that you want to distribute to a larger group of users, but due to security concerns over your SCADA system you can’t do it? If your SCADA system is connected to FlowWorks then you get the best of both worlds…your SCADA system stays locked behind your corporate security, but the data that you want to distribute to others is made available. FlowWorks CANNOT be used to alter data or access your SCADA system and controls in any way.

In the meantime, you and other FlowWorks users within your organization enjoy simple, unlimited access to the information you need, from anywhere with an internet connection. Even if the only thing you use your SCADA system for is to graph data, I guarantee you that FlowWorks will do a better job than your SCADA graphing engine.

I have been doing QA/QC on hydrometric data for many years, and as part of my job I ensure that data being collected is as accurate as possible.  This extends to the instruments collecting the data – today I’m going to talk about troubleshooting a tipping bucket rain gauge, and some of the tools I use within FlowWorks to do so.

If you use a tipping bucket rain gauge you may notice that from time to time the funnel can become clogged with dirt, mud, leaves and other forms of debris.  Clearly a plugged rain gauge will not collect accurate rainfall or precipitation data!

The key is to be able to quickly identify a plugged rain gauge so it can be cleaned out without delay.  There are two ways to do this – accessing your online data (like you could if you are a subscriber to FlowWorks), or manually checking the unit in the field.  I’m going to review both of these options in this article.

Identifying A Plugged Rain Gauge Through Data Analysis

Identifying a plugged rain gauge can be easy when you know what to look for and if you have access to right analysis tools.  If you are lucky enough to be receiving live data, you will be able to identify a plugged rain gauge as often as you check the data.  Historical data is ok too because you will at least be able to identify data sets where the rain gauge was plugged and make sure to disregard that data during further analysis.

A Completely Plugged Rain Gauge

You can tell a rain gauge is completely plugged when there is no rainfall data being recorded when you clearly know that is raining. So if you are looking outside your window and its pouring rain and your live rain gauge isn’t showing any rainfall data, it is probably safe to assume that it’s plugged.  Or if you can compare the data to another rain gauge in the same area they should show similar rainfall.

In the figure below, the data from two rain gauges located in close proximity are graphed using the FlowWorks graphing tool.  The two rain gauges should show similar rainfall but during January 2, 2010, the top rain gauge basically became completely plugged.

Partially Plugged Rain Gauge

Sometimes a rain gauge is only partially plugged.  If this is what has occurred then you would see ‘weird’ rainfall patterns.  That is because during rainfall the gauge will start to fill with water and then the water will start to slowly trickle trough which looks like constant low rainfall and it will tend to continue long after the rainfall has stopped.

In the figure below, the data from two rain gauges located in close proximity are graphed using the FlowWorks graphing tool.  The two rain gauges should show similar rainfall but during the last week of August 2008 the bottom rain gauge became partially plugged.  The constant slow filtering of the rainfall is quite obvious and this is a common indicator that the rain gauge is plugged.

Identifying A Plugged Rain Gauge Through Inspection

The other way to check if a rain gauge is plugged is by pulling it apart on a site visit.  You will either see the funnel clearly plugged or the collection cylinder may be full of water and not draining.  Remove the cylinder to drain the water and make sure the funnel is completely clear of debris.  If the cylinder is not full of water but you still have suspicion that it is plugged, you can pour some water slowly into the cylinder and if the water does not drain or drains very slowly then there may be a partial plug.

Here in the Pacific Northwest it has been raining almost everyday this month. The rain gauge station closest to my house has recorded over 550 mm (22 inches) for November, which is considerably above average.

We have had several storms during this period, but very little flooding issues. My neighbour and I were talking last week after one of the storms and he commented how much it rained the previous night (the local rain gauge measured 27 mm). I agreed with him that it did seem like a good one, but later that afternoon I did a quick analysis using FlowWorks’ Intensity- Duration- Frequency Analysis tool and it turned out that the storm wasn’t “significant”.

So, what constitutes a significant rainfall event and how did I used the IDF analysis tool to quickly determine the severity of the storm?

The basics: What is an IDF Curve?

Here’s the simple answer: An IDF curve tells you how rare a given rain storm is.  Take that storm I looked up from the other night.  It is intuitive to understand the idea of how many mm or inches of rain falls.  It’s not quite as easy to say how often that storm might occur?  Every 1 year? 2 years?  Maybe it was a 1-in-10 year event? An IDF curves helps to quantify that, so you can actually say to your neighbour over the fence, yeah, it seemed like a lot of rain but really we get a storm or two like that every November.

I’ve oversimplified it, but that’s ok.  Read on for a more detailed explanation.

The Official Definition of an IDF Curve

An Intensity-Duration-Frequency curve (IDF Curve)  is a graphical representation of the probability that a given average rainfall intensity will occur (yeah, what a mouthfull!)

Rainfall Intensity (mm/hr), Rainfall Duration (how many hours it rained at that intensity) and Rainfall Frequency (how often that rain storm repeats itself) are the parameters that make up the axes of the graph of IDF curve. An IDF curve is created with long term rainfall records collected at a rainfall monitoring station. I’ll get into the details of how a to create an IDF curve and how much data you need in a future post, but needless to say, you need a lot of data. And the more data you have, the more accurate your curve will be.

How to Interpret an IDF Curve

Rainfall intensity in the IDF Curve is the average rainfall depth that falls per specific time duration. Simplified, high rainfall intensity indicates that it’s raining really hard and low intensity that it’s raining lightly. Typically the rainfall intensity is stated in mm/hr in Canada and in inches/hour in the United States.

Take a look at the graph above. The y-axis shown the rainfall Intensity in mm/hr, and the x-axis shows the rainfall Duration.  There’s the I and D” in the IDF.

The nearly parallel lines on the IDF Curve represent probability, or Frequency (yes, the “F” in the IDF).  So the 10-year line would represent rainfall events that have a probability of occurring once every 10 years. Another way to put it is that the probability of a 10-year magnitude storm (or greater) occurring in any given year is 1/10 or 10%, and of a 50-year storm occurring 1/50 or 2%. I should note that the information presented in the graph is based on statistical analysis of past data, rather than a prediction of actual storms.

Each plotted line in the graph represents rainfall events with the same probability of occurrence, in a range of durations (durations are shown on the x-axis). A 10-year storm can therefore be of any duration – a 10-year 30-min storm, a 10-year 2-hour storm or a 10-year 12-hour storm.

Finally, the last line on the curve is the actual rainfall event, based on the data collected from the local rain gauge.  In this case it falls below all the parallel lines.  Where (and if) the line crosses any of the parallel probability lines, would represent the actual Intensity, Duration, and Frequency of the storm.

Where Can you Find an IDF Curve?

IDF curves are available for many locations in Canada, produced by the Environment Canada’s Meteorological Service of Canada (formerly Atmospheric Environment Service). They are updated periodically, many as recently as 2005, and are available for free download from their FTP site.

A different system of illustrating rainfall statistics exists in the United States. Areas of same statistical rainfall depths are mapped for specific return periods and storm durations. There iso-hyetal maps are called TP40s (Technical Paper No. 40) and can be found for free download on the US National Weather Service. These links are great starting points for understanding rainfall behaviour in different areas of the US or Canada. Local or specialized agencies may have their own rainfall statistics that more closely emulate local conditions and experience, or particular uses for the rainfall information. Examples of these agencies include state/provincial transportation departments, municipalities, environmental protection agencies, etc.

FlowWorks and IDF Curves

FlowWorks can provide you with a quick severity analysis for a storm event.

Did the rain that fell yesterday meet or exceed the 10-year storm? Do you need to report to your City Council the possible reasons why flooding occurred during today’s big storm event? FlowWorks has a tool that can easily answer those questions. By linking your rainfall station to FlowWorks and using our Rainfall Analysis Tool you can plot the storm event as it occurs on the station’s IDF Curve in a matter of seconds. Many of you have likely gone through this exercise using a spreadsheet and found it to be cumbersome and time consuming. The analysis can be redone instantly as new data appears in the database. I have many clients who will “watch” a storm event as it rolls in from the comfort of their desk and send out their operations crews as a storm event hits a certain severity rating to areas where they know that may have issues.

The analysis can also be easily done on all the historical data in your database. The example graph below shows that rainfall that fell near the District of North Vancouver’s rain gauge August 13, 2009 exceeded the 1 in 10-year event for short duration storms (5-15 minutes) and exceeded the 2-year event for a 2-hour storm.

If you’re interested sign up for a free online demo where we can take you through the process of integrating your existing data and climate stations into the FlowWorks system.   Want to know more? Stay tuned for my upcoming articles on “How to Create an IDF curve”, and “What are the other uses for IDF Curves”.

I am a practising Professional Egineer who does A LOT of data collection applications, both for my clients as well as for the 150 or so employee needs within my own firm. When someone asks me what kind of data logger they should use, I always start by asking them where the data logger will be located, and what it will be used for. There are plenty of choices! Here’s a few of the systems and applications that are currently connected to FlowWorks.

Telog

We have some small water and sewer treatment plants that talk to FlowWorks using Telog’s wireless 1XRTT modem. We like the Telog products (particularly the 3307 and 3314), as these units are very reliable and they have some very flexible telemetry options (including dialup phone, wireless, and direct Ethernet connections).

ISCO

ISCO 2150 area-velocity meters in sanitary sewers come in via ISCO’s wireless 1XRTT system. The ISCO’s are purpose-built and hence not as flexible as the Telog wireless system, but the ISCO’s are compact units that generally get the job done well enough.

Marsh McBirney

There are a few Marsh McBirney FloDar’s connected to FlowWorks. These units were plugged into the Telog RU33 product, which acts as a data recording and telemetry module for the FloDar.

ADS

There is an ADS FlowShark connected to FlowWorks. We don’t have a lot of experience with these yet, but our client out East seems to be happy enough with the unit. It uses wireless 1XRTT just like the Telog and ISCO systems.

Satellite Stations

We have remote stations that use satellite because there is no other option where these sites are located. Right now we have Campbell Scientific and Unidata Neon systems connected. We know that Campbell Scientific systems have been around for a long time and have a proven track record. The Neons also seem to be holding up well.

The bottom line is that there are several ways you can do any particular data collection application. We are always doing new applications, and we keep on top of what’s out there on the market, what works well and what doesn’t. Feel free to ask us for a bit of advice the next time you are looking to do a new data collection application!  We work with an expanding list of logger manufacturers, and we provide unbiased advice.

Are solar panels worth it?

There are a lot of hydrometric, sanitary, and rainfall/climate monitoring stations sending data into FlowWorks. Many of our clients have asked us if it’s worth putting a solar panel system on their stations to extend the run times between battery changes. I know there are people who will disagree with me, but my personal opinion is that generally the answer is No.

The main reason to have solar power on your station is to either eliminate or extend the run time between battery changes. There’s also a bit of a “green” look to them. But here’s my main arguments for not bothering:

1. Any station should be able to run for at least 2 or 3 months on battery power, including those that run on the wireless telemetry systems that Telog, ISCO, ADS, and other manufacturers make. You should be visiting a station to do other station maintenance more often then that anyway, so battery changes shouldn’t be the only reason to go to a site.
2. If the main reason you want solar is for the Green Theme, that’s great, but the station still needs a battery, which still has to be recycled eventually just like a non-solar station.
3. Any solar panel large enough to operate a station reliably is usually an easy vandal target. Solar panels are favorite and very expensive targets for guns.
4. If the panel is very small (like a trickle charger you can buy at an automotive store), you won’t get a huge benefit from it. But they are cheap enough that when they get vandalized you won’t miss the money as much.

Absolutely there are times when solar is a good idea. If you can secure the site against vandalism, or if the site is very remote (and hence not that likely to be vandalized), then if you can stomach the extra expense go for it. Solar panels are still fairly pricey, and they can add up to a large part of the bill for a typical monitoring station. Otherwise, save your money and put it towards more monitoring sites instead.

How Can FlowWorks Remote Cameras Create Stop-Motion Video?

It’s easy.  FlowWorks Wireless Cameras send images from a remote installation based on motion sensing and timed intervals.  This allows us to find a balance between image quality and available wireless bandwidth.  When it was time to make a stop-motion movie, routines in the FlowWorks server strips out night-time images and string the daytime ones together into a movie file. 

How a FlowWorks Wireless Camera helped The Eagle Creek Culvert Replacement Project

In this case the District wanted the camera to monitor traffic around a very congested section of Marine Drive in West Vancouver.  Automated traffic lights were used to alternate the single lane traffic.  This keepsake project video was produced as a side benefit after the project was done.  The District also has a permanent visual record (some 125,000 images in all) of the construction for future reference.

Off to the Olympics: What’s next for the Wireless Camera Station

The portable camera is now being moved to a traffic congestion area to monitor access to Cypress Mountain during the Olympics. 

More Information?

Take a look at our FlowWorks Demo video.  After the video you can fill out our demonstration request form.  Or, you can fill it out directly below.  One of our staff will contact you shortly to set up a live demonstration.

 A client has been using FlowWorks for several years, and is now ready to do some sewer inflow & infiltration (I&I) analysis work.  The client downloads a block of data, or uses the FlowWorks I&I analysis tool for this purpose.

When you do this type of analysis, you remove a dry weather flow pattern template from the total flow data.  It is essential that all of the data be in Standard Time, otherwise you run the risk of using dry and wet weather templates that are shifted relative to each other by 1 hour (dry weather often being taken when Daylight Savings Time is in effect, while wet weather events are often during Standard Time).  The result is sometimes subtle and difficult to see, but often leads to the wrong answers being generated in the analysis.

 We’ve seen this happen with lots of other applications:

 -        Operations staff will look at data and want to know when the early morning low sewage flow comes, in order to plan for some maintenance work in the pipe.  Not being sure if the data is in Standard or Daylight time causes confusion.  On FlowWorks, nearly everything is always in Standard time.

-        Comparing data from 2 different rain and storm sewer stations (one running in Standard Time, the other in Daylight) causes confusion and puts a 1 hour error on the timing of the rain peak relative to the storm peak.

Whenever we have a choice, we always run our data collection platforms in Standard Time as we feel it is best practice, and avoids as much confusion as possible.  It is true that there is an inconvenience associated with all of the data being stored in standard time, usually when the data is being used for very casual review by someone who is not used to Standard Time, or if trying to pin down the time that an actual event (such as a sewer overflow) occurred.  However, we feel the long-term benefits of keeping everything on the same time signal outweigh the inconveniences.  If you find you have an application where you absolutely must have the correction for Daylight time applied to your data, talk to us!  We do have some workarounds for you.

After you press the button, you can simply paste a copy of the graph into Word, Excel, email, or any other document that can work with images.  Thanks Ottawa!

Essentially, if you have sites that vary quite a bit in their usage, you can switch to these plans which automatically adjust based on the amount of data traffic you use.  This probably won’t help too much for many of your stations, as we usually already have Telus clients setup on what is now the cheapest rate plan ($30/500 MB).  The only stations that risk going over 500MB/month are the video camera stations, so it may be worth asking your Telus representative to switch you to this plan for your camera stations.  If you don’t have a Telus rep, you can always call Andy MacCormack at TAC Mobility who is very helpful (604-817-2224).  Also, if you use laptop aircards with Telus, your organization may be able to save quite a bit of money by switching to this plan.

Many of you reading this will be following us from our previous website. The new and improved FlowWorks hopefully is going to blow your socks off with some of our new features. Particularly, we hope you enjoy playing around with the new map-based interface to all of your stations. Also, be sure to check out all of the new support material, including plenty of how-to videos. Hopefully you’ll learn something new about how to use FlowWorks to full advantage.

For those of you who are brand new to FlowWorks, make sure you watch the introductory video to get the overview of what it’s all about, then dive right in to trying out the demo!

On behalf of everyone here at the FlowWorks team, Welcome!