The Milwaukee Metropolitan Sewerage District (MMSD) is a regional government agency that provides water reclamation, flood management, and other services for about 1.1 million customers in 28 communities in the Greater Milwaukee area. Headquartered along the Menomonee River near downtown Milwaukee, MMSD serves 411 square miles that cover six watersheds. It has two water reclamation plants, located at Jones Island in Milwaukee and at the South Shore in Oak Creek.
As a regional water treatment giant, MMSD is a big energy consumer, using energy to pump and move water, aerate sewage, and process sewage byproducts. Currently, MMSD facilities heavily rely on natural gas: in 2011, the energy budget was $14 million, with 52 percent for natural gas. Meanwhile, MMSD produces a large amount of carbon dioxide (CO2): in 2007, CO2 emissions from its facilities were 91,800 metric tons while the reporting rule threshold is 25,000 metric tons. Upon entering the 2010s, in order to reduce the energy and money spent on existing water management and industrial operations, MMSD established a set of goals for institutional change, ranging from integrated watershed management to internal energy use.
In 2011, MMSD adopted the 2035 Vision that aims to achieve zero overflows, zero basement backups, improved stormwater management, and increased energy efficiencies. Guiding principles of the 2035 Vision include:
Future planning, design, and operational decisions will be based on a sustainable bottom line approach, considering economic, environmental, operational, and social values.
Water quality leadership and collaboration will foster strategic alliances to develop regional, watershed-based approaches to protecting and improving water quality.
MMSD recognizes sustainability as an overall core value and operational philosophy. In 2005, it adopted an Environmental Sustainability policy to carry out its role as an environmental steward for the Greater Milwaukee watersheds. To commit to the policy, MMSD looks to: encourage and optimize the use of renewable, recyclable, eco-friendly materials; reduce energy consumption and emissions from fossil fuels; and have a positive impact on the region’s economic, social, and environmental resources while maintaining the desired level of services in a financially responsible manner.
In 2009, MMSD released “Fresh Coast Green Solutions,” an educational guidebook, to promote the use of green infrastructure within the region. In 2012, MMSD received the US Water Prize for its pilot watershed-based permitting program that offers southeast Wisconsin a more sustainable form of water resource management. The watershed approach, encouraged by the EPA, applies management planning to the natural boundaries of watersheds rather than being confined to political jurisdictions or individual industries. Watershed-based management not only addresses specific water problems, but also targets a variety of chronic issues that contribute to a watershed’s decline. The success of this approach relies on:
- Working with whole watersheds (looking to Nature’s boundaries, not man’s).
- Using sound science (applying scientific data, tools, and techniques).
- Enlisting public involvement (working with concerned individuals, agencies, or organizations).
- MMSD’s 2035 Vision focuses on two strategic areas: watershed management and energy efficiency.
Integrated Watershed Management
The goals are to integrate activities of watershed partners, integrate management of urban and rural stormwater, and achieve zero combined sewer overflows (CSOs) or sanitary sewer overflows (SSOs). The integrated approach seeks a balance between the gray infrastructure of the watersheds, which consists of roads, pipes, and treatment plants, and green infrastructure, which relies on natural landscape features, such as forests, floodplains, and wetlands, as well such as porous pavements to infiltrate, evaporate, capture, and reuse water.
Currently, the Deep Tunnel dominates the gray infrastructure, successfully capturing 98 percent of polluted water since it became operational in 1993. The Deep Tunnel is a storm water storage system that runs for 28 miles deep beneath the city of Milwaukee. It is capable of keeping 520 million gallons of polluted runoff out of Lake Michigan until the water can be processed through the city’s two sewage treatment plants. MMSD will also expand the use of green infrastructure through acquiring additional land as river buffers, and increased capture and harvest of rainfall.
Climate Change Adaptation
The goals here are to use energy more efficiently, to increase the percentage renewable energy, and to anticipate and plan for changes in the water system due to climate change. By the year 2035, MMSD aims to:
1. Meet 100 percent of its energy needs with renewable energy sources, with 80 percent being self-produced.
2. Provide for 30 percent sequestration of its carbon footprint through the Greenseams Program, an innovative initiative to prevent future flooding by protecting water-absorbing soils.
3. Reduce its carbon footprint by 90 percent from its 2005 baseline.
4. Anticipate, to the greatest extent practicable, and respond to, a range of climate change impacts when considering surface water, groundwater, and the management of stormwater and floodwater.
To achieve the energy efficiency objective, the first step is to minimize energy use. The Jones Island Water Reclamation Facility is currently upgrading the aeration system with a higher efficiency blower that is expected to save up to $300,000 per year. The South Shore Wastewater Reclamation Facility is also increasing its anaerobic digester gas production for the plant’s electricity use. This is expected to save up to $600,000 per year.
Another step is to maximize the use of renewables, including landfill gas (LFG), regional biosolids, sewer thermal, solar, and wind energy. The $43 million MMSD Landfill Gas Project will replace natural gas with landfill gas for the system’s energy use. In 2010, MMSD signed a 20-year agreement with Veolia Environmental Services (VES) to transport the LFG produced by its Emerald Park Landfill to Jones Island through a 19-mile-long pipeline. The gas began flowing in January 2014. MMSD will pay VES 48 percent of the price it pays for the natural gas, which will save tens of millions of dollars over 20 years.
Concurrent with the sustainability mission, MMSD has been supplying Milorganite® (Milwaukee’s Organic Nitrogen), a fertilizer made from the biosolids that remain after the sewage water reclamation process is complete. Since 1926, the sale of Milorganite® has largely reduced sewer rates.
“Looking forward to the next 25 years, MMSD sees a quarter century of efficiency, innovation, and sustainability,” MMSD states in its 2035 Vision, forecasting a healthier Milwaukee region and a cleaner Lake Michigan. By 2035, MMSD also expects success in fostering green facilities, improving energy conservation and efficiencies, and promoting renewable energy use.