superior, wisconsin
Protect water Resources and Coastal Areas
Storm Sewer Improvements
(projects valued at $6,796,242 and currently under construction)
Billings Park Storm Sewer and Water Quality Basin (Phase I)
This project will ultimately reduce storm water and surface water flows to combined sewers through construction of a system of separate storm sewers. The project consists of constructing storm sewers and a water quality basin designed in accordance with Wisconsin Department of Natural Resources criteria to provide attenuation of peak flows and reduction of total suspended solids prior to discharge. The goal is to reduce the frequency and volume of basement backups as well as reduce or eliminate discharges from the combined sewer treatment plant.
South Superior Storm Water Interceptor Project (Phase II)
Phase II of the South Superior Storm water Interceptor Project consists of the installation of a storm water interceptor and a network of sewer mains. The storm sewers will connect to the storm sewer interceptor where storm water will be routed to a water quality basin. Keeping storm water from the sanitary sewer system will benefit the entire City by reducing system-wide impacts and potential surcharging and overflows during severe rain events.
Promote Low-Carbon Energy Generation and Consumption
Methane Flare at the Superior Landfill (valued at $1,200,000)
The City has completed the construction of a methane gas collection system and companion flare at the Moccasin Mike Landfill. This system collects methane gas generated by the decomposition of municipal solid waste and combusts it, breaking it down to carbon dioxide, which is many times less harmful to the environment than the release of methane gas.
The methane gas is destroyed via a newly installed flare. The City is able to measure and sell these volumes of gas as "carbon credits" or "offsets" on the open market. Superior has become a member of the Climate Action Reserve, a national offsets program working to ensure integrity, transparency and financial value in the U.S. carbon market. The rewarding part for the City is that our landfill was among the first landfills in the nation to be registered with the Climate Action Reserve. In addition, this innovation provides a new revenue stream for our important enterprise fund, the landfill.
Solar Bee Aeration System Installation (July of 2008)
Please note that this project is a Wege Small Cities Sustainability Best Practices Award applicant for 2010.
The 90 million gallon overflow basin for Combined Sewage Treatment Plant (CSTP#2) co-located at the main wastewater treatment facility in the City of Superior provides storage volume and biological treatment for combined sewage. The basin utilizes aeration stabilization where microorganisms use oxygen to degrade organic material. The original aeration system for the basin was one of the largest energy users in the treatment process. In 2008, the original aeration system was near the end of its life cycle and required major upgrades or replacement. The City of Superior installed four Photovoltaic Mixing Units (Solar Bees) to achieve aeration requirements and improve treatment efficiency. Solar Bees are solar powered mixers which continually bring the water from the bottom of the pond to the top. As the low-oxygenated water from the bottom of the pond comes to the surface, oxygen is absorbed through contact with the air. This mixing of the pond accelerates the normal purification process. Surface re-aeration is significantly more efficient than forcing air to the bottom of the pond in pipes, then letting it bubble up through the water with the hope that the water absorbs the oxygen as the air passes through it.
Because the Solar Bees were predicted to yield substantial energy savings, the project was attractive to Focus on Energy, a program which works with eligible Wisconsin residents and businesses to install cost effective energy efficiency and renewable energy projects. The City was successful in securing a Focus on Energy grant for 25% of the project cost.
Project Benefit
Energy savings are based on changing the number of aeration blowers and the blower run time strategy to reduce both total kilowatt hours usage as well as demand kilowatts. Future wet weather management strategies will most likely bring more flow to CSTP#2. Higher flows coupled with more stringent effluent limits truly necessitated maximizing the treatment efficiency of the pond. The fact that the Solar Bees are powered by the sun, a completely "green" energy source, gave the City of Superior the opportunity to show environmental stewardship at no additional financial cost.
The Solar Bees cost approximately $160,000 to install. In 2009, the first full year of Solar Bee operation, the kWh energy savings represented $18,000. Based on the first few months of 2010, the savings are expected to increase to $20,400 annually. A conservative estimate, not including the Focus on Energy grant funds, would yield an 8-year payback. When factoring in the grant, the payback will take place in 6 years.
The City of Superior is pleased to offer these "green" savings to its 9,827 wastewater rate payers.
Adopt Green Land Use and Building Design
Larger Recycling Containers Doubles Tonnage
Last year, the Superior Common Council decided to offer citizens a 65-gallon cart for their recyclables (as opposed to an 18-gallon bin). The shift increased municipal fees for recycling from $19,379 per month to $30,378 per month. This initiative has increased participation in the curbside recycling program; and has doubled the tonnage recycled to 78.82 pounds per person per year. The single-stream recycling containers offer an easy option for residents while preserving valuable landfill airspace.