Coaches' Classroom

FREE Regulatory Training - Coming to a Location Near You!

We are offering FREE training on Managing and Operating for Regulatory Compliance across the state. No matter where you manage and/or operate a water system, there will be a regulatory training offered near you. This 4-hour course provides hands-on activities, scenarios and discussion and covers:

• Strategies and resources to comply with drinking water regulations such as backflow prevention and cross-connection control rule, storage tank rule and lead and copper rule.
• Tips to prepare for your next sanitary survey.
• Regulatory updates on operator certification and new EPA requirements under America’s Water Infrastructure Act.

This training has been approved for training units and meets the new operator requirement for regulatory training.

For a full list of regulatory training locations and dates, visit our Training Opportunities and Resources for Water Systems webpage and select “See schedule and register for free drinking water regulatory training.”  You can also Google search "CDPHE training opportunities." 

Check back often as this list will be updated as new trainings become available. We are working hard to increase our training offerings.


➽ David Dani, Local Assistance Unit

Coming down the pipe

Tracer studies and mixmaster tanks

Starting with the publishing of Safe Drinking Water Program Policy 4 in 2010, the department division began an effort to reassess all surface water treatment plants to ensure they use proper disinfection of surface water to meet both 4-log removal and inactivation of viruses (i.e. 99.99% removal and kill) and 3-log removal and inactivation of Giardia Lamblia cysts (i.e. 99.9% removal and kill). In 2014, the reassessment effort was restructured to provide more guidance and assistance to public water systems, and was named the Disinfection Outreach and Verification Effort (DOVE). DOVE includes an assessment of disinfection and documents treatment at all active surface water treatment plants. There were approximately 360 treatment facilities active in 2014. To date, the division has completed roughly 150 of those assessments with approximately 210 more to go.

A major issue that has arisen over the years is whether a treatment plant is over-estimating its baffling factor that it uses in relation to a tank that achieves contact time to kill viruses or bacteria. The baffling factor is essentially a penalty applied to each tank or pipe segment that estimates short circuiting in that particular tank. Most unbaffled tanks have a high degree of short circuiting, so these tanks typically receive credit for about 10% of the operating volume. For example, a rectangular concrete clearwell that operates at 10,000 gallons may only use 1,000 gallons in the calculation for disinfection treatment. Therefore, a baffling factor of 0.1, which represents 10% of the volume, is approved for most tanks. However, if there are special flow configurations and baffle walls within a tank, a tracer test may be run at the facility to determine the volume of water acting towards disinfection. This empirical testing at a facility is the most accurate method for determining whether the proper assumptions are being used to perform disinfection calculations, and the division recommends that each public water system runs the empirical testing at their own facilities.

Prior to the 2014 DOVE initiative, the division worked with the Colorado State University to determine appropriate baffling factors for pressurized tanks in series. These results were published by the division and CSU together. Also prior to 2014, a commercially available tank called the Flexcon® Mixmaster BAF120 was being used at certain public water systems. The Flexcon® company claimed a baffling factor of >0.8. After review at the time, the division allowed 0.7. In 2015, the division received information that perhaps the 0.7 baffling factor was an overestimation. Therefore, since the division had allowed many of these tanks to be installed, the division performed a set of baffling factor tests on the BAF120 tank and determined that the 0.7 baffling factor is correct. The division published an alternative acceptance document summarizing our findings. It is important to remember that the BAF120 tanks must be plumbed correctly and inspected during installation to ensure proper hydraulics (see figure).

Recently, additional manufacturers have come to market with tank systems that are designed to receive baffling factors similar to the Flexcon® Mixmaster tank series. Most of these commercially available tank systems are meant to assist small systems that have limited footprints and budgets in achieving appropriate disinfection contact time. Unlike the previous effort with the BAF120 tanks, the division will not perform tracer testing on behalf of manufacturers. Rather, the division will accept third-party-generated tracer test data and analysis that meet our tracer test guidance and make a determination of the baffling factor. Once a determination is made, the division will publish the baffling factor acceptance on our alternative acceptance page. Prior to gaining acceptance, proposed tanks will be approved with a 0.1 baffling factor unless a site specific tracer study is performed.

➽ Tyson Ingels, lead drinking water engineer and Gordon Whittaker, drinking water coach

Ask Aqua Man

Lead and Copper Rule - Sampling

Dear Lea,

Thank you for your concern. Per the department requirements, lead and copper samples must be taken after water in the plumbing of the building has remained stagnant for a minimum of six hours. No maximum stagnation period has been defined because many different water usage patterns exist within a community. A flushing procedure is not allowed prior to sampling. The most representative sample results will occur when sampling follows normal water use within the residence. It is also important to remember that evaporative cooling units, ice makers, dishwashers, and washing machines can use water automatically and should not be in operation during the minimum six hours of stagnation time.

You may find additional guidance on the lead and copper rule webpage.

  

Happy sampling!

-Aqua Man

Did you know?

Storage Tank Rule

Questions around wetwells are now included in the sanitary survey. If you haven’t seen a question during your most recent sanitary survey, you’ll probably hear it during your next one.

Why are we interested in wetwells? 

A wetwell is a specifically designed system that pumps water from one place to another, usually against gravity forces (e.g. pumping water upwards or uphill). We are interested in wetwells because some wetwells fall under the definition of a finished water storage tank. Regulation 11 (11.28(1)(c)) states that any “tank or vessel owned by the supplier that is located downstream of the entry point and is not pressurized at the air water interface” is subject to the storage tank rule. Additionally, chapter 7 of the design criteria states “All tanks storing finished water including distribution pump station wetwells must meet the requirements of Chapter 7.” Unpressurized wetwells are an important part of the storage tank rule that the state is looking to improve on identifying in order to protect public health.

Starting this year we’ve begun a three year process to discuss and identify unpressurized wetwells during sanitary surveys. If the inspector finds a wetwell that meets the definition of a storage tank it will be added to the supplier’s Safe Drinking Water Information System inventory and the storage tank plan. 

Having wetwells in the storage tank plan will necessitate quarterly inspection, unless there is an alternative inspection plan in place. Since the department hasn’t previously required that wetwells be included in the storage tank plan, we will not be issuing any violations for failing to perform periodic inspections of previously unidentified, unpressurized wetwells until 2022.   

However, we will be looking for any sanitary defects and significant deficiencies associated with wetwells, especially those associated with any existing hatches, vents and overflows. Recent sanitary surveys have found debris, foliage, spiders and even a chipmunk carcass in wetwells. Unpressurized wetwells, like all storage tanks, need properly screened vents, water tight hatches and protected overflows to protect the quality of the finished water. 

The department encourages suppliers to be proactive in addressing the addition of unpressurized wetwells to storage tanks plans. If you have unpressurized wetwells, contact your compliance officer and update your inventory. Add any unpressurized wetwells to your storage tank plan and begin conducting and documenting periodic inspections.

Now when the inspector asks about vertical turbine wetwells during your next sanitary survey, you’ll know why.


➽ Greg Naugle, Field Services Section Manager

Simple Fixes

Storage Tank Inspections

The Storage Tank Rule (Section 11.28 of Regulation 11) requires all public suppliers of water with finished water distribution system storage tanks to conduct comprehensive storage tank inspections every five years or on a department accepted alternative schedule. Suppliers operating such tanks must complete their first comprehensive inspection on or by April 1, 2021 and subsequently every five years thereafter. Finished water storage tanks that are not inspected and maintained can present a pathway for microbial contamination into the tank, which constitutes a sanitary defect.

While inspection of water tanks should be a priority, please be aware that operator safety is of paramount importance when conducting tank inspections, especially comprehensive inspections. Never inspect a tank if there is any question about the safety of the personnel involved.  

Comprehensive tank inspections are more robust than periodic inspections and include a thorough inspection of all external and internal components of the storage tank. As with periodic inspections, the goal of completing comprehensive tank inspections is to identify any sanitary defects that could be present. These defects cover all aspects of the condition of the storage tank including but not limited to sanitary, structural, and coating systems conditions, as well as security and safety concerns. 

Common examples of tank sanitary defects identified during inspections include, but are not limited to, the following:

• Access opening with no sanitary seal (i.e., metal on metal hatch) or a damaged gasket.
• Unscreened tank vent or overflow.
• Blistering of interior coating to the degree where it is peeling into the water.
• Greater than one inch of sediment on the tank floor.
• Unsealed or inadequately sealed tank penetrations.
• Visible contamination inside the tank.  

The inspection method that the supplier chooses to complete a comprehensive inspection largely depends on the type of storage tank being operated and whether the tank can be pulled off line. In some cases, the supplier may choose to contract with a company that dives into the tank to inspect it internally with the use of both video and still photos. 

At the conclusion of the inspection, the contractor will typically provide the supplier with a written inspection report. The department has reviewed numerous comprehensive tank inspection reports and has frequently found that the reports have identified what the department deems a sanitary defect but the report states the defect as a recommendation or in some cases there is no mention of any needed follow-up action. If the inspection report includes any finding that constitutes a sanitary defect as a recommendation or does not mention that any action is needed, the supplier must respond to it as a sanitary defect. The supplier needs to include and complete a corrective action schedule for any sanitary defect in the written inspection plan. Failing to do so results in a treatment technique violation of Regulation 11 that requires notification to the department no later than 48 hours after the violation occurs and completion of a Tier 2 public notice.

Please keep in mind that it is the responsibility of the supplier to understand what constitutes a storage tank sanitary defect and to correct it. The department’s tank inspection checklists highlight in bold which questions are sanitary defects depending on a Yes or No answer. These checklists are available on our website. 

In addition, the department has a Sanitary Defect Applicability Policy (Safe Drinking Water Program Policy # DW-010) that outlines what constitutes a sanitary defect in water distribution systems including storage tanks. This policy is available on the drinking water policies webpage.

For questions concerning finished water storage tank inspections and what constitutes a sanitary defect, please call the department at 303-692-3500. 

➽ Cathy Heald, Non-Community Groundwater Unit Manager

Success Stories

System Improvement Pilot Success

Pine Drive Water District and Beulah Water Works District are two small surface water systems located about 30 miles southwest of Pueblo in the Beulah Valley. While the systems are located only a few miles apart from each other, their water sources are located in different drainage basins. The importance of this was highlighted during a drought in 2002, as one system’s water source dried up entirely, while the other system’s source sustained productivity. The operator in charge at the time came up with the idea to install an emergency pipeline that would allow the systems pipe water back and forth during emergency situations. Over the years, this interconnect has been used a handful of times, but years of non-use affected the pumps and generator, necessitating repairs.  

In 2016, the systems pursued the division’s System Improvement Pilot, which is a pilot program created to help systems address pressing infrastructure needs and optimize operations. Both Pine Drive Water District and Beulah Water Works District joined the program and began the process of repairing the interconnect. Through the program, the systems collaborated on an intergovernmental agreement to share water and participated in operations and maintenance training. They also designed and rerouted the interconnect to take advantage of existing gravity flow and elevation grades in the area, rather than relying on a generator to pump the water through a vault.  

The interconnect proved exceptionally useful in the summer of 2018, when drought conditions struck the area again. Both systems’ water supplies were dwindling when a rainstorm over the Junkins Fire burn scar brought ash down into the creek that supplied Pine Drive Water District, which rendered that supply impossible to treat. The combination of these events put the system at risk of running out of water. Beulah Water Works District’s supply was replenished by the storm and was not tainted by the ash. Beulah Water Works District was able to use the interconnect to supply water to Pine Drive Water District, thus maintaining pressure and protecting the system from contamination until Pine Drive’s water supplies were replenished later in the summer. 

Pine Drive Water District and Beulah Water Works District demonstrated resilience in the face of emergency situations by installing an interconnect between the two systems and creating an intergovernmental agreement to share water during those emergency situations. It is worth noting that there are many factors to take into account when considering an interconnect with another system, and this approach may not be right for all systems. 

➽ Kaitlyn Beekman, communications and special projects

Strategic Planning

Developing a 10-year Road Map for the Safe Drinking Water Program

The Water Quality Control Division has two programs for two different federal rules. The Safe Drinking Water Program implements the Safe Drinking Water Act, and the Clean Water Program oversees the Clean Water Act. In 2017, the Clean Water Program developed a 10-year roadmap outlining its strategy to address water quality issues related to ammonia, nutrients (nitrogen phosphorus and chlorophyll), selenium, temperature, arsenic and cadmium through 2027. The roadmap strategies include goal development, evidence development, goal implementation,work group efforts and outreach. The roadmap also includes specific timeline milestones for those strategies and rulemakings involving key regulations 31 and 85. The Safe Drinking Water Program intends to develop a similar planning roadmap for the 2020s. 

The Alamosa waterborne disease outbreak investigation report completed in November 2009 contained nine major recommendations for the department to reduce the risk of waterborne disease outbreak associated with drinking water at public water systems in Colorado. Implementing those recommendations essentially became the Safe Drinking Water Program's roadmap for the 2010s though we never formally made that designation. All of the recommendations from the report have been implemented and continue to be followed, although addressing aging infrastructure is an ongoing national struggle.

Looking ahead at developing a roadmap for the 2020s means evaluating federal actions that the state is required to adopt and implement, like the long term revisions to the lead and copper rule, and other federal activities like unregulated contaminant monitoring. Additionally, we will look at what kinds of revisions we can make to regulations, policies and guidance to help improve our program implementation and best protect public health considering resource limitations. Stakeholder input will be critical to develop a comprehensive roadmap. Please watch for more information, and join the conversation.

➽ Ron Falco, safe drinking water program manager