In Harrison, Your Grinder Pump's Build Date Sets the Default for Who Fixes It
On a Harrison listing, the waste-disposal line usually comes down to one word, "sewer" or "septic." The Tennessee disclosure form gives sellers the same two choices, "City Sewer" and "Septic Tank." Neither one tells you who pays when the pump in the side yard quits. Under the Hamilton County Water & Wastewater Treatment Authority's rules, the answer often comes down to one date. Residential grinder pumps and STEP systems "constructed after May 1, 2019, will not be maintained by the WWTA" unless the WWTA Board approves maintenance for that particular development.
So two houses on the same stretch of Highway 58, both listed as public sewer, can come with very different jobs for the owner. Here's how that split works and how to find out which side of it a house is on before your inspection window closes.
WWTA's schedule of wastewater rates effective October 1, 2026 has two columns. The first 100,000 gallons a month cost $20.45 per 1,000 gallons. The grinder column charges $22.50 for the same tier. For a home with a meter under one inch, the minimum bill is $28.69 for gravity service and $31.56 for grinder service.
The gap between those columns comes straight from the rules. A low-pressure customer whose grinder or STEP system WWTA maintains pays the standard rate times 1.10. The same rule says systems built after May 1, 2019 are "not subject to the 1.10 surcharge," because WWTA isn't maintaining them. The rate sheet puts it this way: "Customers served by a low-pressure system maintained by the WWTA will be charged a 10% maintenance fee according to flow," and gravity customers pay an $8 Private Service Lateral Program fee.
That leaves four setups a Harrison home can have:
| Setup | Who maintains the pump | Rate per 1,000 gallons, first tier, from Oct. 1, 2026 | Paperwork to request |
|---|---|---|---|
| Gravity sewer | No pump on the property | $20.45 plus the $8 lateral program fee | Confirm service type with WWTA |
| Grinder or STEP built before May 1, 2019 | WWTA | $22.50 | Confirm maintenance status with WWTA |
| Grinder or STEP built after May 1, 2019 | The owner, unless the Board approved the development | No 1.10 surcharge by default; the maintenance rate if the Board approved the development | Board approval status, pump age, service records |
| Septic | The owner | No sewer bill unless sewer becomes available | County septic permit record |
The third row needs the most homework. Systems there don't pay the surcharge, but WWTA can still choose to maintain a specific post-2019 development with Board approval, and every customer in an approved development then pays the maintenance rate. Being a newer build tells you which rule applies. It doesn't tell you how that rule came out for a particular subdivision.
The surcharge comes to $2.05 per 1,000 gallons at the first-tier rates above. A household using 5,000 gallons a month would pay about $10 more on a maintained grinder system than without the surcharge, or a little over $120 a year. That's simple arithmetic from WWTA's posted rates, not a quote for any particular bill.
Here's what the owner of an unmaintained pump takes on instead. In a homeowner FAQ from the manufacturer E/One, a completely installed grinder pump system runs $3,000 to $6,000, depending on the type of system, the soil on the lot and the distance to the sewer tap. On how long a pump lasts, E/One says a properly installed unit can be expected to need repair after 8 to 10 years. Some last well past 20, and the company's average time between service calls is 10 years.
Put those numbers next to a calendar. A pump installed in a 2019 or 2020 build in Harrison is getting close to that 8-to-10-year range now. Whoever buys the house is the one who'll find out how it holds up. The lower monthly bill is real, and so is the pump that comes with it. A buyer comparing two houses near the same price should count both.
Gravity sewer runs downhill. Pumped systems need electricity. WWTA's Quarterly Report No. 8, filed August 13, 2026 under its federal consent decree, logs a dry-weather overflow on May 24, 2026 at Harrison Bay Station, 8321 Harrison Bay Road. About 1,875 gallons spilled, and the report blames a power outage. WWTA hooked up a generator, cleaned the site and rated the impact minimal.
That's a WWTA station with WWTA crews behind it. A grinder pump in a basement or side yard has the same weak spot when the power goes out. After the April 2020 tornado outages, Chattanoogan.com reported that WWTA asked affected customers to cut back on water use and skip high-water-use appliances, and sent crews to empty tanks on the systems it maintained. Whether a house gets that kind of help after a storm depends on the same question of who maintains its pump.
Daily habits matter too. E/One's guidance is to flush only water, human waste and ordinary toilet paper. Wipes, feminine products, grease, paint, strong chemicals, sand and kitty litter should stay out. WWTA's April 2024 grinder application lets WWTA charge for damage caused by foreign material like wipes, grease and kitty litter.
Buyers looking at Harrison septic homes along the lake sometimes assume the sewer question doesn't apply to them. WWTA's published rules say otherwise. A property next to a street, public way or easement with a public gravity or low-pressure sewer has to connect at the owner's expense. The rule continues that sewer charges begin once the owner "has access to sewers," "regardless of whether the sewer connection has been made." WWTA's own FAQ explains that state law lets it require homeowners to pay sewer charges, stop using the septic system and connect if sewer is available.
The disclosure form the seller fills out picked up a related question. The version dated January 1, 2026 asks:
Was a permit for a subsurface sewage disposal system for the Property issued during a sewer moratorium pursuant to Tenn. Code Ann. § 68-221-409? If yes, Buyer may have a future obligation to connect to the public sewer system.
The same form says sellers don't have to get an inspection or any other investigation to fill out the disclosure. That means a "no" or a blank on question 29 reflects what the seller knows. It isn't a records search. If connection ever comes up, WWTA's rules set the standard residential tapping privilege fee at $800, and that fee doesn't cover furnishing or installing the service line.
Every item below goes back to an office that holds the actual records:
Sellers can do the same steps ahead of time. A listing that can answer "gravity, grinder or septic, and who maintains it" on day one saves the buyer from finding the answer halfway through their inspection period.
Which phone number do I call about a grinder pump alarm? WWTA's materials list two. A September 2023 WWTA letter to grinder pump homeowners gives 423-209-7842 in its alarm instructions, and the April 2024 grinder application gives 423-209-6409 for alarm reports. Call WWTA to confirm the current number for your property and keep it somewhere easy to find.
Did WWTA's rates change this year? Yes. The first-tier rate went from $19.66 per 1,000 gallons on the October 1, 2025 schedule to $20.45 on October 1, 2026, roughly a 4 percent increase.
Does every post-2019 grinder home in Harrison maintain its own pump? Not necessarily. The rule is the default, and the WWTA Board can approve maintenance case by case for specific developments. The parcel's status with WWTA is what settles it.
This post is general information about published rules and rates. It isn't legal, financial or engineering advice, so please confirm your property's situation with WWTA, Hamilton County or the right professional before you rely on it.
If you're looking at a Harrison home and the listing says "sewer" without saying which kind, I'm glad to help you line up the WWTA and county records before your inspection window closes. Reach out to Ricky Streeter and let's connect.
Whether you're buying, selling, or investing, I’m here to guide you every step of the way. Contact me today!
Get In Touch With Our Team To Learn More
