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Local strategy map
Watershed integrity

ON TO 2050 calls for the preservation and enhancement of the region's aquatic systems and identifies strategies that are relevant in specific areas. The watershed integrity local strategy map shows percent impervious surface by catchment, which is one of many indicators that can be used to assess the quality of aquatic resources.

Sensitive watersheds

Small watersheds with less than 10 percent impervious land cover are more likely to have better water quality and maintain a higher level of species diversity. These watersheds often have large areas of natural lands, which provide critical ecosystems services such as water purification. However, many of these watersheds are largely composed of agricultural lands, which can have significant impacts as agricultural runoff can contribute nitrogen, phosphorus, and other pollutants to streams, rivers, and wetlands.  

Protecting natural lands and restoring corridors between larger natural cores is a critical strategy to maintain the region’s aquatic resources. Critical partners, such as Forest Preserve and Conservation Districts, Land Trusts, and other conservation organizations lead the way in protecting land through direct acquisition or conservation easements. Stewardship activities can help ensure that natural lands continue to filter and clean water resources.

Land use planning techniques play a critical role in protecting and enhancing aquatic systems. Encouraging infill and redevelopment, as well as using clustering or conservation design techniques when development is slated for agricultural and natural lands, can help the region retain open space. Existing natural areas, open spaces, headwaters, high priority lakes and streams, and riparian zones can be protected through land use planning strategies. When new development takes place, it should protect natural drainage and hydrology, minimize the impact of impervious surfaces, and provide natural buffers along waterways and waterbodies. At the site-scale, county and municipal development ordinances can encourage or require the use of green infrastructure practices to minimize the impact of impervious surfaces, improve the quality, and reduce the volume of stormwater runoff.

Agricultural land management policies, such as those outlined in the state’s Nutrient Loss Reduction Strategy, can help improve the quality of agricultural runoff entering our lakes and streams. Such practices include the use of cover crops, terraces, filter and buffer strips, and grass waterways to reduce nutrient and soil loss, rebuild soil organic matter, sequester carbon, and minimize denitrification. Partners like the Natural Resources Conservation Service (NRCS), and local Soil and Water Conservation Districts promote these techniques. The McHenry County Conservation District already encourages the use of NRCS-approved land resource management plans for farming activities near natural areas.

Impacted watersheds

Small watersheds with 10 to 25 percent impervious land cover typically show signs of reduced water quality, though most aquatic ecosystems remain intact. These watersheds typically have low to moderate levels of development, with significant tracts of agricultural and/or natural areas interwoven into the landscape.

Key recommendations for these areas include a range of land use and planning strategies. Local communities should create and implement multi-objective watershed plans, and incorporate water resources management into local planning through zoning codes and land development ordinances. Local communities should also protect and maintain high-priority natural areas, with an emphasis on preserving important ecosystem services.

Communities in these impacted watersheds will likely continue to face development pressure. Existing natural areas, open spaces, headwaters, high priority lakes and streams, and riparian zones can be protected through land use planning strategies as well as acquisition. Critical partners, such as Forest Preserve and Conservation Districts, Land Trusts, and other conservation organizations lead the way in protecting land through direct acquisition or conservation easements. Stewardship activities can help ensure that natural lands continue to filter and clean water resources. 

Using clustering or conservation design techniques when development is slated for agricultural and natural lands can help the region retain open space and the critical ecosystem services these areas provide. The region’s most widely known example of a conservation design subdivision is Prairie Crossing in Grayslake, Illinois. The community is located in an impacted watershed that has experienced a large amount of development pressure in recent years. Rather than following a more conventional development pattern, local residents instead pushed for a more ecologically sensitive approach. Today, the community is 60 percent open space, with 359 homes surrounded by 3,000 acres of preserved prairie, pasture, and wetland.

When new development takes place, it should protect natural drainage and hydrology, minimize the impact of impervious surfaces, and provide natural buffers along waterways and waterbodies. At the site-scale, county and municipal development ordinances can encourage or require the use of green infrastructure practices to minimize the impact of impervious surfaces, improve the quality, and reduce the volume of stormwater runoff.

Non-supporting watersheds

Small watersheds with 25 to 60 percent impervious land cover are composed of moderate to dense residential, commercial, and industrial development, with only limited areas as farmland or natural habitat. These areas typically show clear signs of degraded stream health and waterways do not meet their designated uses under the Clean Water Act. However, habitat restoration is still possible and planning efforts should focus on slowing the growth of impervious cover, reducing the impact of stormwater runoff, and re-establishing critical habitats, like riparian areas. Many of the region’s protected lands are within these watersheds; stewardship activities can help ensure that natural lands continue to filter and clean water resources.

Creating and implementing multi-objective watershed plans can help communities make strategic improvements to enhance water quality. At the site-scale, county and municipal development ordinances can encourage or require the use of green infrastructure practices to minimize the impact of impervious surfaces, improve the quality, and reduce the volume of stormwater runoff. Infill and reinvestment in existing developed areas can actually improve water management in older neighborhoods by triggering the installation of stormwater best management practices.

Like many communities in the region, Park Forest is committed to protecting the natural environment while also enhancing the area’s economic vitality and promoting a high quality of life for residents. In December of 2017, the Village officially adopted a new unified development ordinance (UDO) containing updated zoning and subdivision regulations that will guide development during the coming decades. Under the ordinance, all new streets will be designed with stormwater best management practices to reduce the volume of stormwater runoff and improve water quality.

Urban drainage watersheds

Small watersheds with more than 60 percent impervious land cover are characterized by dense residential, commercial, and industrial development. In many cases, the topography, hydrology, and species composition within these watersheds have been fundamentally altered due to development and industrial practices. As a result, these areas typically have low water quality and species diversity. And yet in recent years, targeted restoration of riparian areas and watershed-wide activities to better manage stormwater have led to water quality improvements.

 


Infill and reinvestment in existing developed areas can actually improve water management by triggering the installation of stormwater best management practices. Each redevelopment site represents an opportunity to enhance the environmental performance of a property and contribute to local and regional natural resource enhancement. Many aspects of development proposals, such as building design, landscape choices, and site planning, can improve stormwater management and water quality.

 

Expansion of site-scale greening -- particularly with native and drought- and flood-tolerant landscape materials and trees -- can help to retain stormwater. One such example in the City of Chicago is providing a model for the rest of the region and the nation. The Space to Grow program works with Chicago Public Schools to transform largely concrete schoolyards into attractive, engaging playgrounds while also providing valuable stormwater management for the surrounding neighborhood. Retrofitting large areas of impervious surface as well as neighborhood and community parks to provide stormwater services can help reduce localized flooding and improve water quality.

Development and aquatic resources

The integrity of the region’s aquatic resources refers to the chemical, physical, and biological quality of these systems to support both human and non-human use. Maintaining these systems' health is important not only for communities and residents, but for the economic, ecological, and recreational values that they convey to the region, in monetary terms as well as the ecosystem services they provide.

Watershed integrity is heavily influenced by development decisions. As the level of development, or imperviousness, increases within a watershed, the amount of stormwater runoff entering a waterway can increase, leading to reductions in water quality and a cascade of other impacts.  Waterways in areas with lower imperviousness have a greater chance of being higher quality or being restorable to high quality, though they may still suffer impacts from agriculture, transportation systems, and other alterations of the landscape.
 

ON TO 2050 calls for integrated water resource management, yet the strategies used across the region should vary to reflect the context and assets of those places. This local strategy map identifies the varying levels of development by small watersheds across the region and the corresponding strategies that should be prioritized to improve water quality. However, this regional analysis is a starting point, and efforts to improve water quality should be tailored to fit the location.