Frequently Asked Questions

General FAQs

Q. What is a CSO?

A. A Combined Sewer Overflow (CSO) is a discharge of raw sewage mixed with stormwater into local waterways during a wet weather event, such as a rainstorm. Overflows occur when there is too much of this mixture for the sewer system or treatment plants to handle. To relieve pressure in the system and minimize backups into homes and businesses, excess sewage flows into local waterways.

CSO Papillion Creek System

Q. Why are CSOs a concern?

A. CSOs contain raw sewage, which can be the source of disease-causing organisms. In addition, the pollutants in CSOs can adversely affect fish and other aquatic life, and can create aesthetic problems – such as with odors and trash.

Q. What should residents do during a CSO event?

A. Residents should avoid water contact sports and activities (for example, swimming, boating, wading and fishing) during rainfall and snowmelt conditions, and when any discharge is observed from a CSO pipe.

Q. What is a separate sanitary sewer system?

A. A separate sanitary sewer system is a collection of pipes located in streets and easements that are designed solely to transport sewage away from the sanitary fixtures inside homes, businesses and industry and convey it to the wastewater treatment plant. This system protects public health by removing human and industrial wastes so they can be properly treated before discharge. Cities that have these systems must also have a separate sewer system to handle stormwater.

Separate Sewer System

Q. What is a separate storm sewer system?

A. A storm sewer system is a collection of inlets and pipes – located in streets and easements – designed to transport rainwater and snowmelt away from streets, homes and businesses and convey it to various receiving waters (such as streams and rivers). Storm sewers are usually much larger than sanitary sewer system pipes because peak stormwater flows from typical rain events greatly exceed sanitary flows.

Q. What is a combined sewer?

A combined sewer is a sewer that is designed to convey both stormwater and sanitary sewage. During dry weather, sanitary sewage alone is conveyed. During wet weather, a mixture of stormwater and sanitary sewage is conveyed. A combined sewer overflow (CSO) is a release of untreated wastewater from a combined sewer directly into the environment. This occurs during wet weather events, when the added presence of stormwater exceeds the capacity of the sewer system or treatment plant.

Q. What other communities are subject to CSO regulations?

A. There are currently over 772 U.S. communities subject to CSO regulations. Most of these communities are located in the Northwest, Great Lakes, and Northeast portions of the country. This map shows those who have combined sewer systems and are on the EPA’s list of regulated CSO communities.

Communities subject to CSO regulations

Q. How can I help improve water quality?

A. Even when CSO controls are implemented, stormwater from our City will flow to streams and rivers during wet weather events. This stormwater picks up pollutants as it flows across the land, whether it comes from streets, open areas, or rooftops. You can help to reduce this pollution by:
• Disposing of household chemicals and used oil properly, and not pouring them down storm sewers
• Inviting the City to make a presentation to your civic association or neighborhood group
• Picking up after your pets
• Fixing fluid leaks from vehicles

Q: What are the circumstances that cause the sewer system to combine and then overflow?

In the combined sewer service areas, one pipe exists to convey both sewage and storm water. When the runoff from rain adds to the sewage component of the flow in sewer, the system relieves itself to a creek or river at the CSO outfall. If there were no designed overflow point, the excess sewage mixture would overflow at other low-lying locations, like basement floor drains.

Q: During the course of the project will you be reporting industries that are not in compliance with regulations and how will this work?

The City has a program and staff assigned to enforce the sewer codes for industrial dischargers, and control of industrial discharges will be considered in evaluating CSO alternatives.

Q: Do all users pay the same rates?

The rates for sewer user fees are based on the costs of service by customer classification. All customers of a given class (residential, commercial, industrial…) pay at the same rate, based on their contribution. All customers (inside and outside Omaha) will help fund the CSO improvements necessary to meet the federal mandates that will improve water quality for the greater Omaha region.

Q: How are people on homestead land going to afford even the most minimal increases? There are lots of elderly people in the basin and even small increases will be difficult?

Wastewater service is a utility, like water and gas service, with charges based on contribution. There is currently no mechanism for providing special rates based on ability to pay. The overall financing of the CSO program will require additional review of options for addressing customer hardships.

Q: What is the difference between raising our taxes to pay for the improvements vs. sewer fees?

Wastewater service is considered a utility, like water and gas service. Federal law requires that costs for wastewater service meet certain “equity” requirements, in terms of cost recovery. The overall financing of the CSO program will require additional review of options that may include a portion of tax revenues.

Q: What are the water standards for Nebraska? How are they defined?

Nebraska water quality standards and definitions can be found in the Nebraska Department of Environmental Quality’s Title 117, http://www.deq.state.ne.us/.

Q: Why don’t we have a sewer use tax, which would be deductible, instead of a sewer use fee?

Wastewater service is generally considered a utility, like water and gas service. Federal law requires that costs for wastewater service meet certain “equity” requirements, in terms of cost recovery. The overall financing of the CSO program will require additional review of options that may include a portion of tax revenues.

Q: Why don’t we focus on stormwater management? What is the City’s position?

In developing its CSO control plan, Omaha does need to consider how the CSO controls will be integrated into a comprehensive watershed management plan. However, the mandated deadlines for CSO control are unlikely to allow for simultaneous development of one regional management plan.

Q: What will the cost to the individual homeowner be? Will the City incur the necessary costs for hook-ups or changes to the home/business or will that be a homeowner/business cost?

As currently envisioned, sewer separation work that is incorporated into the CSO control plan will be funded through fees collected from all users of Omaha’s regional treatment system. The impact of recently approved rates will mean annual increases of $1.10 to $1.60 per month through 2010. Subsequent note increases could force rates to rise to approximately $50 per month by 2017.

Generally, there should be no direct costs assessed to individuals’ homes or businesses where new sewers are installed.