Sanitary defects associated with wellheads are among the most frequent findings cited by field service section staff during sanitary surveys. However, wellhead issues are often among the issues most easily corrected. So how can suppliers be proactive and avoid being cited for a wellhead sanitary defect finding in the first place, or worse - a waterborne disease outbreak?
First, be familiar with the following resources and refer back to them often:
Drinking Water Policy DW010 provides examples of conditions at sources that are sanitary defects and could allow contamination to enter the source water.
Chapter 3 of the State of Colorado Design Criteria for Potable Water Systems (design criteria) specifies construction standards for groundwater sources. By reference, section 3.2.1.a of the design criteria requires that all wells must be constructed in accordance with the latest edition of the Division of Water Resources’ Water Well Construction Rules (2 CCR 402-2 Rules and Regulations for Water Well Construction, Pump Installation, Cistern Installation, and Monitoring and Observation Hole/Well Construction).
Next, regularly inspect and evaluate wellheads for sanitary defects.
What to check for and correct if found (the following wellhead conditions are not allowed):
Well caps with missing or deteriorated seals or gaskets
Well caps with loose or missing bolts
Wellheads with broken electrical wiring conduits
Cracks or holes in well casings or the well pad around well casings
Improper grading around wellheads and/or standing water around well casings
Wellheads that are in flooded well vaults or submerged under water (see above)
Damaged screens on air vents (well caps with air vents must be properly screened)
Example 1 - Flooded Well Vault: The photo below shows a well and appurtenances in a Flooded Vault
Example 2 - Missing Seal or Gasket: The photo below shows a well cap without a gasket installed.
Example 3 - Broken Electrical Wiring Conduit: The photo below shows an example of a broken electrical conduit at a wellhead.
Example 4 - Unsealed Electrical Supply & Missing Air Vent Screen: The photo below shows a well with an unsealed electrical supply and missing a vent screen.
Example 5 - Damaged Air Vent Screen: The photo below shows a well with a damaged air vent screen.
During a sanitary survey, the supplier’s groundwater wells will be visually inspected during the onsite inspection portion of a sanitary survey. When wellhead sanitary defects are discovered during sanitary surveys they will be cited as significant deficiencies. Suppliers can avoid this by proactively inspecting groundwater sources on a regular basis and promptly fixing any sanitary defects identified.
Conclusion: Unprotected or improperly maintained wellheads can provide a pathway for contamination to enter the source water and can be a source of contamination. Protection of groundwater sources is a critical part of the multiple barrier approach to providing safe drinking water and is a safe and effective way of protecting our communities and promoting a culture of health.
Does your well have sanitary defects? If so, suppliers should proactively identify and promptly correct the sanitary defect(s) that were identified, before they are cited as significant deficiencies during sanitary surveys.
Please reach out to the field services section at cdphe_wqcd_fss_questions@state.co.us with any related questions.
Guidance & Resources:
Division of Water Resources’ Water Well Construction Rules (2 CCR 402-2 Rules and Regulations for Water Well Construction, Pump Installation, Cistern Installation, and Monitoring and Observation Hole/Well Construction)
DNR Division of Water Resources’ Well Construction & Inspection Resources
