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

Preparing for Harmful Algal Bloom Season

Water that is warm, slow moving and high in nutrients can cause harmful algal blooms to form in waters above ground like reservoirs. With the weather warming up, managing these waters to prevent these blooms becomes critical for water safety. Certain types of cyanobacteria, also known as blue green algae, produce unpleasant taste and odors in water. Some blue green algae are also capable of producing cyanotoxins which can create health risks for humans and animals. The toxins can be problematic for anyone that ingests them or is exposed through recreational activities. Currently, cyanobacteria is not a regulated contaminant but EPA has published non-regulatory drinking water 10-day health advisories for the cyanotoxins microcystin and cylindrospermopsin based on studies showing that these two strains cause liver, kidney and reproductive toxicity.

Responding to situations where an unregulated contaminant measures above a health advisory is very difficult because there is not a playbook with available instructions like there is with regulated contaminants. In May 2018, Oregon’s capital and second-largest city, Salem, made national headlines by declaring a state of emergency after issuing a “Do not drink” advisory due to elevated microcystin levels in their treated water. Here are a couple of the lessons learned Salem shared after the event:

Do not wait to notify your customers

After receiving initial sample results showing levels above the health advisory, the system spent a couple of days making operational changes to try and lower toxin levels before taking more samples. Because Oregon didn’t have any labs capable of cyanotoxin analysis, they had to ship samples to an out-of-state lab, causing a long turnaround time for receiving results. The system believed it was okay, since they were still responding within the 10-day health advisory window. However, those follow-up sample results came back high and the system issued a “Do-not drink” advisory. The customers and local papers were outraged because they weren’t notified sooner.

Knowing when to lift the advisory is tricky 

After receiving sample results showing microcystin levels were below the health advisory, the city lifted the initial “Do not drink” advisory. The city then issued another “Do not drink” advisory four-days later after receiving additional results showing elevated toxin levels. They waited to lift the second advisory until they had levels below the health advisory for 12 consecutive days.

Between 2018 and 2020, all drinking water systems nationwide serving over 10,000 individuals, as well as a random selection of other systems, are required to sample for cyanotoxins as part of EPA’s Unregulated Contaminant Monitoring Rule (UCMR). EPA will use the test results to see where cyanotoxins are occurring and determine whether or not to regulate them in the future. There are over 100 Colorado drinking water systems required to perform this additional testing and they have been notified. As of May 2019, there have not been detections of any UCMR cyanotoxins in treated water.

Online resources

Learn more about cyanotoxins and how to monitor and prepare for them by reviewing these resources:

• Monitoring guidance created by the Colorado Harmful Algal Bloom Workgroup.
• EPA's  toolkit and webinar Preparing for HABs season. 

➽ David Dani, Local assistance unit

Program Manager's Message

Program metrics supporting a culture of health 

In the third Aqua Talk issue of 2018, I wrote about establishing a culture of health across the entire community of people involved with providing safe drinking water to the public, including state and local health departments, public water system owners, operators and utility staff. I detailed some of the plans to develop a culture of health including training about waterborne disease outbreaks, public notice including health effects language and strengthening communications about drinking water and health with our partners. But how do we measure health and drinking water?

The safe drinking water program developed a number of metrics that we plan to regularly report out on to help us understand how we are doing. The program is involved in many different activities and measures a wide variety of items. We categorized our overall program metrics to include different categories for these metrics. 

Categories for program metrics

Each category is shown below with an example of one metric under that category. 

• Health outcome – Number of waterborne disease outbreaks at public water systems.
• Health risk – Number of systems exceeding the action level for lead.
• Workload – Number of violations issued to public water systems.
• Timeliness – Percent of design reviews completed in 45 days or less.
• Value added – Number of grants and loans issued to public water systems.
• Customer satisfaction – Overall customer satisfaction with sanitary survey inspections.
• Resources – Number of program staff.

There are multiple metrics within each category. Many of the metrics have been measured previously for a variety of reasons, but some will require developing new tracking or reporting mechanisms. Many of these metrics have established target goals, while other metrics are tracked strictly for trending purposes. For example, our target goal for the number of waterborne disease outbreaks is zero. Our goal for design reviews completed in less than 45 days is currently 60%. 

Constructing all this will take some time and effort, but we are aiming to make progress in this year. Once we have finalized the metrics and reporting structure, we will report out to you on our progress. We will report periodically on selected metrics and annually on all of them. We hope that measuring our collective performance in providing safe drinking water to the public and reporting out on that performance, will help us establish a culture of health among all of us involved in making sure that drinking water is always safe.

➽ Ron Falco, safe drinking water program manager

Ask Aqua Man

New EPA requirements in the Safe Drinking Water Act

Dear Reg,

Thanks for your questions and for trying to stay up to date! Actually, it was the United States Congress that passed America’s Water Infrastructure Act of 2018. This bill passed both houses of congress by virtually unanimous votes; President Trump signed it into law in October 2018. This new law covers a vast array of water infrastructure matters and makes several important amendments to the Safe Drinking Water Act. EPA, states and public drinking water systems must ultimately implement the changes. Here are a few of the most important items.

It appears that the next (fifth) round of sampling under the Unregulated Contaminant Monitoring Rule (UCMR5) beginning in the early 2020s will require all systems serving between 3,300 and 10,000 people to collect samples. The current UCMR4 requires all systems serving above 10,000 people to sample and only a few smaller systems to sample. This requirement will become effective only if congress authorizes additional funding to support implementation. So the next step will be for EPA to develop specific rules and then wait to see if congress authorizes the additional funding. The UCMR is primarily implemented by EPA with limited support from states.

Community water systems serving more than 10,000 people will be required to provide Consumer Confidence reports at least twice per year and may do so via electronic distribution. EPA has two years to develop specific regulations for this requirement and is also charged with improving readability, understanding and accuracy. This new requirement will be implemented by the states after they adopt the rule. It is likely that this requirement will not be effective until 2022 or so.

Community water systems serving more than 3,300 people will be required to conduct a risk assessment that addresses natural hazards and resilience and review it every five years. An emergency response plan is also required. EPA is required to guidance and technical assistance on how to conduct the risk assessments and prepare the plans. These documents do not need to be submitted to EPA, but a certification that they were completed needs to be sent to EPA by 2020 or 2021. It appears that states will not have a direct role in implementing this requirement, but in Colorado we intend to stay engaged and help water systems via training, etc. as resources permit. EPA is also required to establish a grant program to help water systems improve resilience.

They were quite a few other changes as well, but these are the key changes involving regulatory requirements. Stay tuned for more information in the future.  

-Aqua Man