Understanding Water Samplers: Types, Applications & Key Features

In water and wastewater management, automatic water samplers are essential tools that support everything from regulatory compliance to operational decision-making. Whether deployed in a treatment plant, industrial facility, or remote field site, these devices provide reliable, consistent data collection with minimal manual effort.

With so many sampler types and configurations available, it’s important to understand how samplers work and where each type excels. This article breaks down the core categories of automatic water samplers, common use cases, and features that help you get the most out of your sampling programs.

Types of Automatic Water Samplers

Whether you're monitoring drinking water, wastewater, or stormwater, the data collected helps protect public health, meet regulations, and keep systems running smoothly. Sending someone out to take samples by hand isn’t always realistic or reliable. That’s where automatic water samplers make a big difference. These tools are designed to collect samples on their own, following a set schedule or triggered by events such as changes in flow or pH, so operators get accurate, consistent data without extra manpower. Choosing the right sampler comes down to your needs, location and requirements. There are a variety of options available when deciding which solution works best for you.

Portable Samplers

Flexible and field-ready, portable water samplers are best for temporary deployments, remote access, stormwater and pretreatment sites. Portable samplers are lightweight, self-contained units often powered by batteries or 12V DC sources. They're designed for easy transport and setup, making them ideal for field crews or sites without permanent infrastructure.

Typical use cases:

• Stormwater runoff monitoring

• Industrial site inspections

• Short-term construction dewatering compliance

• Temporary bypass or overflow tracking

Refrigerated Samplers

Refrigerated samplers help preserve sample integrity and are best for temperature-sensitive applications and lab-quality composite samples. These stationary units include a built-in refrigeration system to keep samples at or near 4°C, as required by EPA and other regulatory agencies. They’re commonly used indoors or in sheltered outdoor locations.

Typical use cases:

• Influent and effluent sampling in wastewater treatment plants

• Industrial pretreatment monitoring

• Long-term compliance programs requiring sample preservation

  
  
  

All-Weather Refrigerated Samplers (AWRS)

Built for the elements, all-weather samplers are permanent outdoor installations designed for direct outdoor exposure in extreme conditions. These ruggedized samplers offer both refrigeration and heating capabilities to maintain consistent temperature control in all seasons.

Typical use cases:

• Remote environmental monitoring

• Stormwater program compliance

• Outdoor sampling where shelter isn’t practical

Composite vs. Discrete Sampling

Composite sampling collects multiple small samples over time or based on flow, then combines them into one container to represent an average. Discrete sampling collects individual samples at specific points in time often used for tracking peak loads, identifying pollutants, or regulatory spot checks.

Choosing between composite and discrete sampling depends on your data needs. Composite samples offer a broader, averaged view of conditions, while discrete samples capture specific moments or events.

Key Features to Consider in Any Sampler

Regardless of type, most modern autosamplers offer advanced features that improve efficiency, safety, and data quality. Here are some of the most valuable capabilities to look for:

Flow-Paced or Time-Based Sampling

Set samples to trigger based on time intervals, flow volumes, or external events. This flexibility is critical for meeting permit conditions like those under NPDES or industrial pretreatment programs.

Communication & Integration Options

Many autosamplers support integration with SCADA, flow meters, or telemetry systems. This enables remote programming, status updates, and data retrieval—especially useful for hard-to-access or unstaffed locations.

Data Logging & USB Transfer

The ability to store thousands of samples, event logs, and configurations allows teams to maintain robust records for compliance or audits. Some models allow easy transfer or cloning of programs using a USB stick.

User-Friendly Programming

Look for intuitive interfaces with simple navigation. Reducing setup time means faster deployment and fewer chances for error in the field.

A Closer Look at the Hach AS950 Series Sampler

One commonly used autosampler series in the field is the Hach AS950, which includes portable, refrigerated, and all-weather models. Known for flexibility and ease of use, these units are often deployed in both municipal and industrial applications. The Hach AS950 samplers support flow-based and event-based triggering, composite or discrete sampling modes, and easily integrate with telemetry systems. Their portability and versatility make them a solid choice for a wide range of applications.

Choosing the Right Sampler for Your Site

Water samplers may work quietly in the background, but their impact is substantial. Whether you're tasked with regulatory compliance, protecting water quality, or optimizing treatment processes, selecting the right sampler type and configuring it effectively can save time, improve safety, and deliver higher-quality data.

When evaluating samplers, consider these four key questions:

• What’s the sampling environment (indoor, outdoor, mobile)?

• Will sampling be based on time, flow, or specific events?

• Is sample preservation (cooling) required?

• Do you require integration with telemetry, flow meters, or SCADA?

Need help selecting the best sampler for your needs?

Contact your Core & Main Supply account manager for expert advice on products, accessories, and availability. Visit supply.coreandmain.com or call 888-885-2673 for more information.

Disclaimer: The information in this article is for educational purposes only and does not constitute engineering or regulatory advice. Features and specifications reflect product documentation at the time of publication.