Reduce Inflow and Infiltration: What Bioaugmentation Can and Can't Do
If you need to reduce inflow and infiltration, you need to fix pipes, manholes, and connections. Bioaugmentation does none of that. It doesn't seal a crack, plug a joint, or keep a drop of groundwater out of your system.
What it can do is narrower. It still matters in wet weather. This post lays out both sides so you can decide where it belongs in your I&I plan, and where it doesn't.
How to Reduce Inflow and Infiltration: What Actually Works
Nothing replaces the physical work. The sources have to be found and closed:
Flow monitoring, smoke testing, and CCTV to find where the water is getting in
Pipe and joint rehabilitation, including CIPP lining and point repairs
Manhole rehabilitation and sealing
Removal of direct stormwater connections to the sanitary system
Lateral programs that address the connections feeding your mains
That work is how you take clear water out of your system. It's also how you reduce the load on your lift stations and your plant. The physical side of I&I solutions is the first line of defense, and a biological program is not a substitute for it.
What Bioaugmentation Can't Do
Be clear about this with your council, your engineers, and your vendors.
It can't stop water from entering the system. The defects stay open until someone repairs them.
It can't lower the peak flow reaching your plant. Wet-weather volume is the same with or without it.
It can't make up for a failed pipe. A collapsed or badly cracked line is a capital project.
Any vendor who tells you otherwise is overselling.
What It Can Do When the Rain Hits
A wet-weather overflow happens when flow is more than the pipe can carry. Part of the pipe's cross-section may already be taken by grease and biofilm before the storm arrives. Less open pipe means the surge backs up sooner. A partial blockage at peak flow can turn into an overflow fast.
Treating FOG upstream keeps more of the pipe open. That's capacity relief. It gives the system more room to absorb the I&I you haven't fixed yet, which is the point of buying time before the next capital project.
One honest limit. How much capacity you recover depends on how much of the restriction is actually FOG. Measure it. Run CCTV and flow monitoring before dosing starts and again after.
Where It Fits in an I&I Program
Use the sequence, not the sales pitch:
Find the sources. Flow monitoring and inspection first.
Fix the biggest contributors. Rehab where the water volume is worst.
Treat the capacity-constrained sections. Look for segments that surcharge in wet weather and show grease or biofilm on camera. That's where a FOG treatment program pays off.
Re-measure. Compare wet-weather performance before and after.
If a problem segment has clean pipe walls and cracked joints, that's a rehab job. Don't dose it.
Map Where FOG Is Costing You Capacity
If your wet-weather problem areas also carry a grease history, that's worth a look. Talk to In-Pipe about where FOG is eating pipe capacity in your system and what a treatment program would add to your I&I plan.
Related reading: Inflow and Infiltration Solutions
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