Wastewater 101

Last updated March 5, 2024

Are you a health department or laboratory professional interested in learning more about wastewater collection and treatment and what your utility partners do to protect human and ecological health? Then you’ve come to the right place! Here, you’ll find a series of videos explaining all things wastewater. Each video is accompanied by a PDF file with the video slides, which you should feel free to download and use, as well as a list of questions you can ask your utility partner to learn more about their system.

Is this not exactly what you’re looking for? Please email us to request the development of a free, custom training program for your organization. Or browse our YouTube channel for additional resources.

Part 1: What is wastewater?

Questions for your utility partner about the nature of their wastewater:

• Do you receive wastewater from a combined or a separate collection system?
• Are there major industries that discharge to your collection system? If so, how many and what types?
• Are there major institutions (universities, hospitals) that discharge into your collection system? If so, how many and what types?
• How extensive is I/I in your system?
• Does your facility accept septage? If so, where does the septage enter your treatment process?
• Is there anything else that would be helpful to know about the type of wastewater you receive?

Part 2: How is wastewater collected?

Questions for your utility partner about how their wastewater is collected:

• What type of collection system do you operate: combined, separate, or mixed?
• Do any other sewer districts discharge to your system/treatment plant?
• How large is your service area? How many miles of sewer and how many lift stations do you (or your member sewer districts) operate?
• Are there any storage facilities (retention basins, deep tunnels) in your system?
• How do you map your collection system? Using as-builts/record drawings? GIS? How up-to-date is your information?
• Where do you currently meter flow, if at all, in your system?
• Do you have an H&H model of your collection system? If so, has it been calibrated recently?

Part 3: How is wastewater treated?

Questions for your utility partner about how their wastewater is treated:

• Do you collect a liquid or a sludge sample for wastewater surveillance?
• If liquid, do you collect it upstream or downstream of screening? Upstream or downstream of grit removal? Upstream or downstream of primary treatment?
• If sludge, does it represent a single clarifier, or combined primary sludge flows?
• Is there any septage added to your process upstream of where the sample is collected?
• Are there any chemicals added to your process upstream of where the sample is collected?
• Are there any solids processing sidestreams added to your process upstream of where the sample is collected?
• Do you have an equalization basin?

Part 4: Where does treated water go?

Questions for your utility partner about their discharge permit(s):

• What influent monitoring requirements does your current NPDES permit contain?
  • What parameters do you need to measure?
  • How frequently do you need to measure them?
  • What type of samples do you need to take and where do you need to take them to satisfy the influent monitoring requirements?
• How do you expect your influent monitoring requirements to change, if at all, in future permits?

Part 5: How is water quality monitored?

Questions for your utility partner about their water quality monitoring program:

• What do you regularly test for in your raw influent, either for permit compliance or for process control?
  • Which of these are measured on grab samples and which are measured on composite samples?
  • How frequently do you analyze for each?
  • Which type of glass-fiber filter is used for your TSS measurements?
  • How easy is it for you to share your raw influent data with your health department and lab partners?

Part 6: Who works in the wastewater sector?

Questions for your utility partner about their staff:

• How many operators do you have on staff?
• How many dedicated lab staff do you have?
• Do you have any dedicated GIS staff?
• Who else in your organization should be part of any email communication about our program?
• Who else in your organization should be part of any ongoing program meetings?

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