Environmental rigor integrated into mobility planning
Any mobility plan has environmental consequences: on greenhouse gas emissions, on air quality, on energy consumption, and on noise. However, the consequences do not always go in the expected direction. New infrastructure designed to reduce congestion can induce new traffic demand and end up generating more emissions than before. A measure to promote electric vehicles can have a rebound effect if not accompanied by policies to reduce motorized mobility demand.
The Strategic Environmental Assessment (SEA) of mobility plans is the tool that allows identifying and quantifying these impacts and ensuring that planning decisions are made with full awareness of their environmental consequences.
Do you need the strategic environmental assessment of your mobility plan or the calculation of its environmental impacts?
We help you comply with regulatory requirements and make planning decisions with full awareness of their environmental consequences.
How we work on strategic environmental assessment
From VAIC Mobility, mobility consultancy, we carry out the strategic environmental assessment of mobility plans by applying the reference environmental impact calculation methodologies in Europe: energy consumption, atmospheric pollutant emissions (NOx, PM10, PM2.5), greenhouse gas emissions (CO₂, CH₄, N₂O), and noise pollution.
The assessment is not limited to quantifying the direct impacts of the analyzed alternatives. It also incorporates the analysis of unintended effects that often go unnoticed in conventional assessments:
- Traffic Induction: new road infrastructure or network improvement can generate additional mobility demand that was not foreseen, reducing or nullifying the expected environmental benefits.
- Rebound Effect: an improvement in vehicle energy efficiency can lead users to travel more kilometers, partially offsetting the reduction in emissions per vehicle.
- Suck Effect: improved accessibility by public transport or bicycle can attract trips that were not previously made, increasing total mobility even while reducing the private vehicle share.
Identifying and quantifying these effects is essential to honestly assess the real environmental impact of a mobility plan and to design appropriate corrective measures.
Regulatory Framework in Catalonia
In Catalonia, the strategic environmental assessment of plans and programs is regulated by Law 6/2009, of April 28, on the environmental assessment of plans and programs, applied in accordance with the provisions of State Law 21/2013, of December 9, on environmental assessment, as established by the eighth additional provision of Law 16/2015, on the simplification of administrative activity.
In the field of transport and mobility, the following planning instruments are subject to the strategic environmental assessment procedure: the Transport Infrastructure Plan of Catalonia, the Airports and Heliports Plan, the Ports Plan, the National Mobility Guidelines, the strategic mobility plans, the specific mobility plans, the urban mobility plans, airport master plans, and the Passenger Transport Plan.
Ordinary procedure
In the ordinary procedure, the developer presents an Initial Strategic Document (DIE), formerly the Preliminary Environmental Sustainability Report, on which the environmental authority issues the Scope Document for the Strategic Environmental Study. From there, the promoting authority prepares the Strategic Environmental Study (EAE), which is attached to the plan’s documentation for initial approval. The environmental authority subsequently issues the Strategic Environmental Declaration (DAE), which must be positive for the definitive approval of the plan.
Simplified procedure
In the simplified procedure, the developer directly submits the Strategic Environmental Document (DAE), on which the environmental authority issues a resolution.
From VAIC Mobility, we accompany plan developers throughout the entire procedure (ordinary or simplified), from the drafting of the Initial Strategic Document to the final Strategic Environmental Study, coordinating with the environmental authority and ensuring that the documentation meets the content requirements and deadlines of the procedure.
Impact calculation methodologies
The technical core of the assessment is the quantitative calculation of the environmental impacts of the plan’s alternatives. We apply European reference methodologies to calculate:
- Greenhouse gas emissions associated with motorized transport, broken down by transport mode and vehicle type, and compared with the reference scenarios of sustainable mobility plans
- Emissions of atmospheric pollutants relevant to urban air quality (NOx, PM10, PM2.5, VOCs), with special attention to low-emission zones and areas with air quality problems
- Energy consumption of the transport system in each alternative, including the energy incorporated in the infrastructure construction
- Noise pollution, especially in areas where the plan foresees significant changes in traffic flows
The results are presented comparatively between alternatives, allowing to identify which option achieves better environmental results and under which conditions.
