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Water Sense
Urban Water Sustainability Council
Overflow Reduction Plan


MMSD's $1 billion Overflow Reduction Plan includes massive construction projects, scientific research and planning, and simple ways for you to help protect Lake Michigan. The entire plan must be finished by the end of 2010.

PLANNING: Water Quality Initiative
This long-range planning effort used the most intensive water quality research ever completed in this region to help determine where it makes the most sense to spend money to reduce water pollution.

ADDITIONAL STORAGE
Treatment plants can only clean a certain amount of wastewater each day. Deep tunnels provide additional space to store rain and wastewater until treatment plants can handle the extra flows.

The Overflow Reduction Plan includes two new Deep Tunnels that increase MMSD's overall storage capacity by more than 30%.

Northwest Side Deep Tunnel
:
Went into operation in March 2006 with 89 million gallons of extra storage capacity. It stretches 7.1 miles with a 20-foot-diameter and is fully lined with one-foot-thick concrete.

27th Street Deep Tunnel
:
To be completed by 2010, the two-mile-long tunnel will add 27 million gallons of storage capacity.

TREATMENT PLANTS
These projects help: improve our ability to handle storms, discharge high quality, clean water from the reclamation facilities, and repair and replace aging equipment.

Dollars invested in treatment plant improvements by year:
2001 $28,471,699
2002 $24,655,872
2003 $16,169,969
2004 $16,703,254
2005 $19,734,700
2006 $17,069,133
2007 $27,657,025
2008 $26,400,000

SEWER CONSTRUCTION & REHABILITATION:
Infiltration and Inflow (I&I)



water leaking into sewer lines is a significant cause of sewage overflows.
Most sewage overflows occur because of the excessive amounts of water that leak into sewers when it rains or the ground is saturated.

Local System Inspections:
Provides funding for communities to help locate leaks in their sewer systems, which account for 3,000 miles of pipe.

Central MIS: The Central Metropolitan Interceptor Sewers carry about 60 percent of the District's wastewater flow. A $380 million rehabilitation project is currently underway to add another 50 years of service life to the Central MIS, which is about 50 miles of MMSD's 300 miles of Metropolitan Interceptor Sewer.

OPERATION & MAINTENANCE


Real Time Controls:
A $14 million upgrade to a complex network of monitors, sensors and computerized weather reporting systems used to maximize performance of MMSD's sewers and treatment plants during storms.

CMOM: The Capacity, Management, Operation and Maintenance (CMOM) program is a national effort that uses science-based techniques and assessment to provide better management of valuable assets and improve financial management for sewer infrastructure. CMOM will help the District and its 28 communities provide better sewer service and maintenance, which will ultimately help save tax dollars.

STORMWATER REDUCTION

These are the things you can do at home and work to reduce the risk of basement backups, sewer overflows and, at the same time, help protect Lake Michigan from polluted runoff, the biggest remaining threat to water quality in the country.

    Downspout Disconnection: Every downspout on your home can deliver up to 12 gallons of rainwater a minute during a heavy storm. In the combined sewer area, many downspouts are connected directly to the sewer, potentially pumping millions of gallons of water into the sanitary sewers when it rains. MMSD is encouraging all property owners to disconnect downspouts from the sanitary sewer system where it can be done legally, safely and in a reasonable manner. Not everyone will be able to disconnect.

    Stormwater Trees: A city's tree canopy can significantly reduce rainwater runoff and save millions of dollars in sewer infrastructure needs. Trees provide many other benefits. A healthy level of tree canopy is around 40 percent. A 2002 analysis of the older sections of Milwaukee found the tree canopy at around 10 percent.

    Rain Barrels: A simple way to store the rain that runs off the roof of your home, rain barrels allow you to capture water that you can use later, during dry periods, to water plants, trees and gardens.

    Rain Gardens: According to the Wisconsin Department of Natural Resources, rain gardens allow about 30 percent more water to soak into the ground compared to a conventional lawn. The gardens help keep water out of the sewer system while attracting birds and butterflies at the same time.

    Green Roofs: A waterproof membrane, soil and vegetation placed on flat roofs combine to capture rain that would otherwise flow off your roof, down a downspout and possibly into a sewer. Rain that falls on the green roof is typically retained in the soil and used by plants or evaporated. Excess rain flows off of the green roof and drains into downspouts. An engineering analysis is required to make sure your building can handle the extra weight of a green roof.

    Porous Pavement: Pavement systems for roads, parking lots or trails can be designed to absorb water by using porous asphalt or concrete, modular block systems or pavers. Porous pavement systems work best in low-traffic areas such as parking lots, driveways, sidewalks, trails or the shoulder of a road. They can be very effective for reducing stormwater runoff.

    FLOOD MANAGEMENT

    When rivers flow over their banks and onto streets or into the basements of homes and businesses, millions of gallons of floodwater can end up getting into the sewer system through floor drains or sewer manholes. It's a devastating problem that can lead to sewer overflows and sewage backing up into basements. MMSD is working hard to manage flooding problems in the Milwaukee area.

    Greenseams: A program aimed at reducing future flooding risks in the greater Milwaukee area by purchasing undeveloped land, which helps slow down rainwater runoff by naturally storing rain where it falls. The Conservation Plan acquires land in areas that are expected to have major growth over the next 20 years. The Conservation Fund (TCF), which has been retained by MMSD to implement the Conservation Plan, is a national nonprofit organization based in Arlington, VA that forges partnerships to conserve America's legacy of land and water resources.

    Milwaukee County Grounds: Construction is underway on this $84 million floodwater holding basin. Capable of storing 260 million gallons of water, the project is one of several that are part of an integrated plan to reduce the risk of flooding on the Menomonee River. Each project depends on the other to provide a level of protection for the 1% probability flood, commonly called the 100-year flood.

    Hart Park: Completed in 2007, the Hart Park Flood Management Project will address severe flooding problems for neighbors and businesses near downtown Wauwatosa. The project also boosted Hart Park from 20 acres in size to 50 acres.