How Chattanooga's Sewer System Works and What Your Bill Covers

Your sewer bill arrives separately from water, but most Chattanooga property owners don't understand what they're actually paying for or why the charge fluctuates. This guide explains the Chattanooga Water Company's sewer service structure, how usage is calculated, what factors drive cost increases, and practical steps to lower your monthly payment.

The Chattanooga Water Company Sewer System

The Chattanooga Water Company operates both water supply and wastewater collection for the city and surrounding areas. Sewer charges are based on water consumption during winter months (December through February), a standard practice designed to exclude irrigation from the calculation since most lawn watering happens in summer.

If you use 1,000 gallons of water in January, you'll be charged for approximately 1,000 gallons of sewer usage, even if your actual wastewater output differs. This winter-billing method protects the utility from inflated charges during summer when families water yards but don't generate proportional sewer flow.

Breaking Down Your Bill

The sewer portion of your Chattanooga Water Company bill typically includes three components: a base charge, a usage charge, and occasionally a stormwater management fee.

Base charge: A fixed monthly fee that covers system maintenance, administrative costs, and infrastructure upkeep. This fee applies whether you use minimal water or substantial amounts. For residential customers in Chattanooga proper, this base charge covers access to the collection network that moves wastewater from your home to treatment facilities.

Usage charge: Calculated per 100 gallons (or per 1,000 gallons, depending on your meter type) based on winter consumption. A household using 5,000 gallons of water during winter months will pay for 5,000 gallons of sewer service for the entire year, even though summer usage may be much lower. This creates an incentive to reduce water waste during the winter billing period.

Stormwater fee: Some Chattanooga neighborhoods with separate stormwater systems may see an additional charge. This covers the cost of managing rain runoff that enters storm drains rather than the sanitary sewer system. Chattanooga's East Brainerd and North Shore districts have been affected by stormwater billing adjustments in recent years.

Why Your Bill Changes

Sewer rates in Chattanooga have increased steadily over the past decade due to aging infrastructure and federally mandated water quality improvements. The Chattanooga Water Company has invested heavily in treating Combined Sewer Overflows (CSOs), which occur when heavy rain overwhelms the system in older neighborhoods like the North Shore and parts of downtown, forcing raw sewage into the Tennessee River.

If your winter water usage increases, your sewer bill will rise proportionally. A household that uses 6,000 gallons in winter versus 5,000 gallons will see roughly a 20 percent increase in annual sewer charges. This is the most direct lever homeowners can control.

Rate increases also occur when the Chattanooga Water Company seeks approval from the Public Utility Commission of Tennessee to cover operational and capital costs. These typically occur every two to three years and affect all customers equally.

Reducing Your Sewer Bill

Since sewer charges are tied to winter water consumption, reducing water use during December through February has the largest impact on your annual bill.

Practical steps:

• Fix leaking toilets immediately. A running toilet can waste 200 gallons per day, adding $40 to $60 annually to sewer charges. This is the single most common source of inflated winter consumption.
• Shorten showers during winter. A five-minute shower uses roughly 25 gallons; cutting to four minutes saves 5,000 gallons over three winter months.
• Run full loads only in dishwashers and washing machines. Partial loads waste water disproportionately during months when every gallon counts toward your annual sewer bill.
• Install low-flow showerheads and faucet aerators. These typically cost under $20 and reduce flow from 2.5 gallons per minute to 2.0 or less.

Chattanooga's water system does not offer sewer bill discounts for rain barrel collection or greywater reuse systems, though some utilities in Tennessee do. Homeowners cannot reduce their sewer charge through alternative disposal methods.

Understanding Your Meter and Reading

The Chattanooga Water Company reads meters monthly. Your winter billing period (the months used to calculate your annual sewer charge) typically runs December 1 through February 28. If you receive a meter reading notice showing unusually high winter consumption, compare it to the previous year at the same time.

A spike of more than 20 percent typically indicates a leak. Common culprits are water heaters, supply lines under the foundation, or outdoor faucet leaks that homeowners overlook during winter. The cost of a professional leak detection service ($150 to $300) is often recovered in reduced sewer bills within one billing cycle if the leak is significant.

Meter errors are rare with modern equipment, but if you dispute a reading, the Chattanooga Water Company will send a technician to verify. There is no charge for verification if the meter is found to be faulty; if it reads correctly, you may be charged a service fee.

Payment and Assistance Programs

The Chattanooga Water Company accepts payments online, by phone, or by mail. Late payments incur a 1.5 percent monthly penalty. Service disconnection typically occurs after 45 days of non-payment.

Low-income households in Chattanooga may qualify for the Utility Assistance Program administered through the city's Human Services Department. Eligibility is based on household income and must be reapplied for annually. This program can cover both water and sewer arrears, though funding is limited and applications are processed on a first-come basis during winter months.

When to Call a Plumber

Sewer backups, slow drains, and gurgling sounds in fixtures indicate problems within your home's drain system rather than the municipal sewer line. A licensed plumber in Chattanooga typically charges $150 to $250 for a diagnostic visit and $500 to $1,500 for repairs involving drain cleaning or trap replacement.

Chattanooga's combined sewer system in older neighborhoods (particularly near the riverfront and Northshore areas) means that heavy rain can occasionally affect service on your end. If multiple fixtures drain slowly only during or after heavy rain, the issue likely lies with the municipal system, not your home. Contact the Chattanooga Water Company's customer service line to report it.

Your sewer bill reflects real infrastructure costs and water treatment requirements. Understanding what drives the charge and where your water goes during winter gives you concrete ways to manage the cost year-round.