Why Dedicated Water Sampling Stations are a Good Practice

Test tubes for water sampling stationNo one wants to mess around when it comes to the quality of water in their community. Water quality management is one of the main public health concerns in any city, town, or county, and it’s absolutely imperative that waterworks professionals take it seriously. Regularly taking samples from the water main and testing them is a key way to judge the quality of the water. It’s possible to collect a sample from several different types of sources, but the one we’re going to focus on here is sampling stations.

We’ll answer all of the most common questions people tend to have about water sampling stations and their alternatives in the following sections. Some forms of water sampling involve water quality intelligent monitoring and flushing stations with sensors and PLCs, but that’s a different application from what we will discuss here. We’re focusing on collecting the sample to be sent to labs to test under the Revised Total Coliform Rule.

Why is water quality testing so important?

The answer here likely goes without saying, but water quality testing is absolutely vital and required to maintaining the health of a community. Some of the worst disease outbreaks of all time have been due to waterborne pathogens. Even though we have made great strides in water treatment and water quality management, ongoing testing ensures that our treatment strategies and the integrity of our distribution systems remain safe. Staying on top of water quality means frequent testing.

Because testing water for signs of potentially harmful microbials is so important, the government regulates how it’s done so that everyone abides by proper water quality standards. The next section will cover some of the major rules when it comes to water quality testing.

What kind of regulations apply to water quality testing?

When a professional in this field takes a sample, one of the main things they’re looking for are total coliforms. These are types of bacteria that are typically not harmful to humans, but they can be important warning signs that something is not quite right.

If you test a distribution system and no total coliforms are present, then it’s unlikely that there are fecal pathogens in that water supply. However, if coliforms are present in a sample, that indicates that the water distribution system might be a vulnerable to other pathogens such as fecal coliform or e. coli.

The federal Safe Drinking Water Act requires public water systems to test for coliforms as well as elements like arsenic, mercury, and fluoride, among many others. These tests are also required to happen at specific frequencies. In this piece, we are focusing on equipment used to take bacteriological samples, but know that water quality testing goes even farther than that.

Additionally, the Revised Total Coliform Rule mandates that if a sample tests positive for total coliforms, then more tests must be performed. A system must then test the sample for either fecal coliforms or e. coli bacteria. Then, within 24 hours, they must take three to four samples at sites near to the sampling site that produced the positive sample. Finally, within the next month of operation, they must take five or more routine samples.

On top of these federally mandated rules, the Environmental Protection Agency has specifically allowed dedicated sampling stations to be used for these purposes. We’ll go over some of the reasons why water sampling stations make more sense than their counterparts in a later section. First, we need to define what a dedicated sampling station is in the first place.

What is a dedicated sampling station?

A dedicated sampling station is a specialized piece of equipment where water operators can collect water samples directly from a distribution system in order to test it for harmful microbials or signs of harmful materials, like the tests we outlined above.

Dedicated sampling stations are convenient places to test the quality of a system’s water. They’re specifically designed and engineered for a single purpose, and they’re vital to ensuring the safety of a water distribution system.

What are the advantages of sampling stations over other options?

Number one is the convenience. When the utility controls the site, it can collect samples at any time. Other options for taking samples from a water system include going into a home or business, which means the operator would have to coordinate with the owner or resident making sure they are there in order to get access to a tap inside. Avoiding this with a dedicated water sampling station also decreases liability issues that might arise whenever water utility personnel step onto private property, such as property damage claims or other serious accusation like sexual harassment.

Another major advantage is that dedicated sampling stations have a singular purpose: To collect samples for water quality testing. When utilities use dedicated sampling stations, they control the tap. That means the cross-contamination potential is lower because it is a single-use tap unlike multi-use taps in kitchens and bathrooms. False positives are also less common with dedicated sampling stations. When the tap is regularly used for purposes other than sampling, it may potentially compromise the integrity of the sample.

A third reason why dedicated sampling stations are considered a best practice is utilities can obtain a quality water sample directly from the water main. If you’re using a home’s sink, as an example, then you run the risk of taking samples filtered through the site plumbing rather than directly from the water main. Dedicated sampling stations enable utilities to get a better representative sample of water that they produce right from the water main.

Another disadvantage of using private or public taps is that your site map can constantly be changing as people move and relocate. When this happens, you will have to resubmit your sampling map to the EPA for approval if your sample location changes from one house to another. With dedicated sampling stations your site map remains the same once you have installed dedicated sampling stations throughout the system.

Drawbacks of Sampling Stations

While there are many benefits of choosing a dedicated sampling station over taking samples from multi-use taps, they also have a few cons you should keep in mind. Obviously, we think the pros far outweigh them, but you should be aware of them, nonetheless.

The most obvious one is the cost of purchasing and installing the dedicated sampling stations. Most utilities will budget a number of stations per year making it easier to completely revamp their system over a period of time. If making the move to dedicated sampling stations, utilities will want to place these into their specs so that any new construction will include them in the plans. Additionally, like any type of operating hydrant there are maintenance costs of replacing seats to keep the stations functioning as design without leaking. These costs are nominal, and all maintenance can be performed from above ground with digging required.

What kind of dedicated sampling stations are out there?

Let’s go through the kinds of dedicated sampling stations Kupferle manufactures so you can get a better idea of what your options are. One thing that all Kupferle dedicated sampling stations share (and that no sampling station should have) are nozzles without threads and no drain/weep hole. As threads collect “gunk” they can possibly produce a false negative if this “gunk” may happen to get into the sample. Additionally, one should never take a water quality sample from any type of hydrant or device that drains to ground as cross-contamination from the ground water may again create a false positive sample.

Eclipse #88 Series

These best-selling dedicated sampling stations all share the same sturdy cast-aluminum powder-coated enclosure. Some are designed for freezing climates while other are for non-freezing (WC designation) areas of the country. The #88-SS and #88WC-SS both utilize an all-stainless steel waterway, while the #88 and #88WC use brass. Kupferle also offers an extreme cold climate model the Eclipse #88-SS-R that allows for the entire waterway to be removed if a freezing incident happens due to a leaking seat or an operator who may have forgotten to pump out the station. This station is for far north locations like the northern US and Canada. To keep water that is caught above the seat when shutting off the stations for cold climates, Kupferle has engineered a way to remove this water by plugging what would be the drain/week hole and running an evacuation line up inside the enclosure to a petcock above grade. Operators would use a small rechargeable Electric Evacuation Pump (sold separately) that they would attach to the petcock at the end of the evacuation line in order to pump out any remaining standing water during freezing seasons.

All the Eclipse #88 series products are easy to service from above ground, meaning crews won’t have to dig in order to do maintenance. The Eclipse #88 products are housed in lockable enclosures so that no unauthorized parties can use them. These enclosures are made of cast aluminum, making them extremely durable.

MainGuard #66 Series

The MainGuard #66 series shares the same stainless-steel waterway at the #88-SS and #88WC-SS but it is housed inside a fabricated aluminum enclosure instead of cast. Like the other sampling stations we’ve discussed, the MainGuard #66 and the MainGuard #66WC are meant to be placed outside where it’s easiest for sampling crews to access them. However, this line of stations has another option. The MainGuard #66MB is designed to be installed inside, perfect for public buildings (like fire stations) that are used for collecting samples. It features built-in mounting brackets, which allow you to place them on the wall with minimal effort.

As noted above, the MainGuard #66 sampling stations are housed in lockable, brushed aluminum enclosures, but an optional plastic dome or bollard enclosure is also available.

MainGuard #95WM

Visually, this type of water quality testing equipment is very different from the other sampling stations we’ve discussed this far. It is a meter resetter sampling stations that is housed inside of an existing meter box. It is easy to install and easy to take samples from using a sampling rod that threads onto the sampling point spring-loaded nozzle (sold separately with carrying case). It has adjustable horns that rotate to accommodate any size/shape meter and are replaceable if broken. Can also be used as a temporary station for additional upstream/downstream samples when needed.

Some other key features include an isolation shut-off maintenance valve, a three quarter inch stainless steel threaded sampling point, and copper horns with brass meter nuts.

MainGuard #94WM

One difference between the MainGuard #95WM and the #94WM is that the former includes a schedule 80 PVC body while this one has a brass body. Same sampling point as above using the same rod and carrying case. Like the 95WM it utilizes a coarse-threaded spring-loaded sampling nozzle that eliminates using any type of force to connect unlike quick-disconnect versions that eventually leak.

MainGuard #77-Hybrid

The hybrid in the name of this product indicates that it has two different functions in one piece of equipment: A sampling station and a flushing hydrant.

We’ve written about the importance of flushing aging water out of your distribution system in the past, and flush hydrants can be helpful tools in that endeavor. This station combined the 2” flushing power of a blow-off with a dedicated sampling point for collecting samples. Like the #88 and #66 series of sampling stations for cold climates it does not drain to ground, but can be evacuated using Kupferle’s Electric Evacuation Pump during freezing seasons.

Eclipse #82WC

Like the above #77-Hybrid, the Eclipse #82WC provides a 2” flushing option to move water quickly before collecting samples but also incorporates a mechanical draining feature to keep it from freezing instead of using the Electric Evacuation Pump. Even in some warm climate areas there can occasionally be a flash freeze now and then. This station is designed to bleed water when temperatures fall below a certain level keeping the water moving and the standing pipe from freezing.

Its stainless-steel waterway is housed in a lockable plastic enclosure.

How do I choose the right water sampling station for my distribution system?

Once you’ve chosen to opt for a dedicated sampling station rather than using a tap that has other purposes, then you need to select the right piece of equipment for your system. There are several considerations that you should take into account.

When choosing the right water sampling stations for your system, you should already know to keep your community’s climate in mind. Some are meant for warm climates where freezing isn’t an issue, while others are built to withstand cold and extreme freezing temperatures.

Since the convenience of a dedicated sampling station is one of the main reasons to add one to your distribution system, the placement of the station is highly important. You’ll want crews to have easy access.

Now you’re ready to make your decision.

We couldn’t possibly turn you from a newcomer to a complete expert in water sampling and water quality management in just one blog post, but now that you’ve reached the end, you should have a good base of knowledge to get you started on the right path.

You now know about the major regulations in place that make water sampling stations necessary, and you’ve read about the reasons why dedicated sampling stations are often a better alternative than taps that are also used for other purposes when it comes to water quality testing. We also discussed the different products Kupferle manufactures to meet these needs, so you should have an informed understanding of the options that Kupferle offers.

With all of that in mind, you should be pretty well prepared to choose the right sampling stations for your distribution system, but if you need some additional assistance don’t hesitate to contact Kupferle at [email protected] or call at 800-321-3990.