3.1B – Planning and Design – Land Development
- Limit disturbance and development of natural drainage features and sensitive areas; such as clearing and grading and cut and fill to reduce erosion and sediment loss; and
- Prepare an effective, approved erosion and sediment control plan or similar administrative document that specifies erosion and sediment control provisions.
Bridges by their nature are built in riparian areas and can have pronounced habitat and water quality impacts if care is not taken to protect sensitive areas from both construction and post-construction impacts. Practices to meet these goals include designing bridges to minimize damage to riparian or wetland habitats and treating runoff from bridge decks before it is allowed to enter watercourses. Bridge maintenance activities should be conducted using containment practices to prevent pollutants, such as paint, rust, hazardous chemicals, and building materials, from entering the water or riparian habitat below. Restoration of damaged riparian or aquatic habitats should be done after bridge construction, maintenance, and demolition (see Management Measure 6B for restoration and mitigation of wetlands and riparian areas).
- Limiting Disturbance
The type and location of permanent storm water management practices should be considered when planning new development including highways, roads, and bridges, such that rights-of-way are sized to accommodate structural controls. Highways and roads should be planned to minimize mileage through areas that might adversely affect sensitive areas, such as wetlands or estuaries. Wetlands that are within the right-of-way and cannot be avoided should be protected with the use of mitigation measures. Highway and road construction should be limited in sensitive areas, and highways should be sited so there is a sufficient setback distance between the highway right-of-way and any wetland or riparian areas. Another consideration is tidal flows to wetlands; highways and rights-of-way should not restrict this flow. Mitigation will be required if wetlands, riparian areas, or estuaries are affected (see Management Measure 6B for restoration and mitigation of wetlands and riparian areas).
- Site fingerprinting is a technique that can be used to protect vegetation and reduce erosion
This practice limits clearing to areas that will be used for buildings, roads, and other infrastructure, leaving undisturbed areas that will be vegetated open space in the final plan. Areas that will remain undisturbed need to be marked off and construction equipment and stockpiles must be excluded to protect the existing vegetation and prevent compaction or erosion. The advantages of site fingerprinting are that natural areas are protected and fewer costs for landscaping are incurred. A disadvantage is that equipment will need to be maneuvered around these protected areas, possibly leading to increased labor hours.
Bridges should be planned to minimize mileage and protect sensitive areas such as wetlands or estuaries. Setbacks should be used for river crossings during construction to minimize disturbance to the riparian area. Bridge construction can adversely impact water circulation in wetland areas, so allowances should be made for these impacts when designing bridges. Areas requiring excessive cut and fill and those that may be subject to subsidence, sink holes, landsides, rock outcropping, and highly erodible soils should be avoided when sitting bridge locations.
Runoff should be directed away from bridge decks and watercourses by diverting it toward land for treatment. This can be accomplished using drains that pipe water along the bridge edge to either side of the shore. Recommended practices for treating bridge deck runoff include ponds, wetlands, infiltration basins and trenches, media filters, bioretention areas, vegetated swales, filter strips, and hydrodynamic devices. The use of scupper drains should be restricted on bridges less than 400 feet long and on bridges crossing sensitive areas.
- Highways and Roads
Disconnect impervious surfaces by eliminated curbs (when local development codes permit) to allow highway and road runoff to be filtered through vegetated shoulders and medians. Eliminating curbs also increases infiltration to ground water. If eliminating curbs is not possible, curbs can be designed with breaks to direct runoff to vegetated surfaces. Care must be taken to ensure that the curb breaks do not receive so much runoff that vegetated infiltration areas are eroded. Storm water control structures should be designed so that the storm water does not run directly to receiving waters. Highway runoff should be routed through a combination of treatment practices or over stabilized vegetated areas such as vegetated shoulders or swales before it enters receiving waters.
- Erosion and Sediment Control Plans
Storm Water Pollution Prevention Plan (SWPPP) describes in detail how a contractor or developer will reduce soil erosion and contain and treat runoff bearing eroded sediments and construction site chemicals. It normally includes the locations and type of pollutants present, as well as practices used on the site for soil stabilization, perimeter control, and runoff treatment, including vegetation practices, structural and nonstructural practices. It also details spill control measures, response actions, and a monitoring program. The SWPPP entails more than filing written documentation. It requires follow-through on the part of both the developer (for implementation) and regulator or permitting agency (for inspection and enforcement). This follow-through can include reviewing and modifying the SWPPP to account for unexpected events that occur after plans have been approved, and adapting to unforeseen conditions on the site. It must also include inspecting and assessing the effectiveness of implemented management practices on storm water quality. In some cases, practices will require maintenance or alternative or additional management practices.
- Alameda Countywide Clean Water Program, New Development and Redevelopment.
- SWRCB, Division of Water Quality, Storm Water Program Discharges of pollutants from construction activities are for the most part regulated under the NPDES permitting program. Regulated entities include all construction sites with one or more acres of disturbed area. Discharges of pollutants from construction sites smaller than 1 acre typically are considered nonpoint sources but might also be regulated at the local level. Construction site operators should contact the municipal department for more information about local requirements, including air quality requirements for dust control.
- Surface Transportation Policy Project (STPP) provides assistance to local transportation agencies, elected officials, and citizen groups to help stakeholders take advantage of the new opportunities available under the federal transportation bill to link transportation to land use, housing, social equity, livable communities, and smart growth.
- California Department of Transportation (Caltrans), Statewide Storm Water Management Program integrates appropriate stormwater control activities into ongoing activities, thus making control of stormwater pollution a part of Caltrans normal business practices.
- Green Highways Partnership (GHP) is a voluntary, public/private initiative that is revolutionizing our nation's transportation infrastructure. Through concepts such as integrated planning, regulatory flexibility, and market-based rewards, GHP seeks to incorporate environmental streamlining and stewardship into all aspects of the highway lifecycle.
- Portland Green Streets Program was approved a Green street resolution, report, and policy to promote and incorporate the use of green street facilities in public and private development. Portland has also adopted a progressive Division Green Street/Main Street Plan to create a pedestrian-friendly commercial district that reflects and reinforces community values, including a focus on sustainable and "green" development. Community interest in sustainable practices encompasses a broad spectrum of ideas and strategies, however, this project looked specifically at green infrastructure opportunities at a conceptual level within the public right-of-way. This was done through a transportation and land use planning process that included extensive community, business and interagency collaboration.
- Santa Clara Valley Urban Runoff Pollution Prevention Program, Hydromodification Management Plan (HMP) was prepared in response to the NPDES Permit C-3 requirements to address the impacts from new and redevelopment projects on stream morphology, habitat, and erosion potential.
- SWRCB & RWQCBs, Clean Water Act section 401 Certification and Wetlands Program, RWQCBs review projects that require a federal permit under CWA section 404 or involve dredge or fill activities that may result in a discharge to waters of the United States. This is to ensure that the State’s interests are protected on any federally permitted activity occurring in or adjacent to waters of the State.
- FishXing Website provides software and learning systems for calculating fish passage through culverts.
- Caltrans Stormwater Water Quality Planning Tool is a database of water quality standards and possible pollutants from Caltrans facilities. This unique tool is another valuable resource being used by Caltrans in its continuing commitment to prevent storm water pollution.
- Caltrans Environmental Handbook, provides guidance on the identification and evaluation of the environment, including cultural resources (Volume 2), biological resource (Volume 3), and community impact assessment (Volume 4).
- Caltrans, Statewide Storm Water Management Plan was approved by the SWRCB in March 2003, describes procedures and practices Caltrans uses to manage pollutants discharged from storm water drainage systems.
- CERES, California Wetland Information System is designed to provide wetland information to the public, educational community, and government agencies. It includes information on wetland mitigation and the mitigation role and responsibility for the California Department of Transportation.
- National Cooperative Highway Research Program (NCHRP), Evaluation of Best Management Practices for Highway Runoff Control includes information on Low Impact Design.
- Washington Department of Transportation (WSDOT), Roadside Manual provides guidance on roadside maintenance, including planning, design, construction, and maintenance. The manual has information on sustainable roadsides, environmental functions, wetlands, water quality, parking area design, erosion control, contour grading, soil bioengineering, and vegetative restoration concepts.
- WSDOT, Highway Runoff Manual provides guidelines that WSDOT, engineering consultants, and many local agencies use to design stormwater systems for transportation projects in Washington State. The manual includes guidelines for retrofitting and design guidance for BMP approaches that many would characterize as LID. The manual also received an honorable mention for Environmental Excellence in the Wetlands, Watersheds, and Water Quality Category in the Federal Highway Administration 2007 Environmental Excellence Awards.
Metropolitan Washington Council of Governments. 1987. Controlling Urban Runoff: A Practical Manual for Planning and Designing Urban BMPs. Metropolitan Washington Council of Governments, Washington, DC.
Richman, T., K.H. Lichten, J. Worth, and B.K. Ferguson. 1998. Landscape Architecture Technical Information Series: Vegetated Swales. American Society of Landscape Architects, Washington, DC.
USEPA. 2005. National Management Measures to Control Nonpoint Source Pollution from Urban Areas. EPA 841-B-05-004. U.S. Environmental Protection Agency, Washington, DC.