Aspen deliberates updating plan that manages stormwater runoff, pollutants – AspenTimes.com

Report on Proposed Updates to Aspen’s Urban Runoff Management Plan

1.0 Introduction: Aligning Urban Development with Sustainable Development Goals

On November 17, the Aspen City Council convened to discuss proposed updates to the city’s Urban Runoff Management Plan (URMP). The primary objective of the updates is to reduce the volume of sediment and pollutants entering the Roaring Fork River from stormwater runoff associated with development projects. This initiative is critically aligned with several United Nations Sustainable Development Goals (SDGs), including:

• SDG 6: Clean Water and Sanitation – By seeking to improve the quality of river water by reducing pollution.
• SDG 11: Sustainable Cities and Communities – By integrating sustainable water management into urban planning and construction codes.
• SDG 14: Life Below Water – By protecting the freshwater ecosystem of the Roaring Fork River from land-based pollution.

2.0 Analysis of Council Deliberations and Key Issues

2.1 Central Point of Contention: Development Thresholds

A significant disagreement emerged among council members regarding the specific thresholds that would trigger mandatory adherence to new stormwater infrastructure requirements. The proposed updates stipulate that a “major grading plan” for runoff management would be required under the following conditions:

• An interior remodel exceeds 50% of the total building footprint on a site where the impervious area is greater than 50%.
• An interior remodel exceeds 75% of the total building footprint on a site where the impervious area is less than 50%.
• The total area of addition, repair, or demolition exceeds 1,000 square feet.

2.2 Competing Perspectives on Sustainability and Economic Viability

The debate highlighted differing views on balancing environmental protection with economic feasibility, a core challenge in achieving SDG 11.

• Council Member Bill Guth expressed concern that requiring major exterior construction for interior remodels constituted an overreach. He questioned the return on investment from a holistic environmental perspective, suggesting the community impact of additional construction could outweigh the benefits of the stormwater system.
• Mayor Rachael Richards supported the proposed thresholds, arguing that environmental protection measures should be treated as essential code requirements, similar to electrical and fire safety standards. She emphasized that this approach is necessary to bring properties into compliance with modern standards for land and water stewardship, and that waiting for demolitions to trigger updates would unacceptably delay progress on environmental goals.

2.3 Financial Considerations for Development

The city provided cost estimates associated with the proposed requirements, which present a financial factor for developers aiming to contribute to sustainable urban infrastructure.

1. Cost to hire a stormwater system engineer: $25,000 to $30,000.
2. Cost to install a stormwater management system: $115,453.

3.0 Proposed Technical Solutions for Sustainable Stormwater Management

3.1 Recommended Green Infrastructure and SDG Alignment

City staff and consultant Wright Water Engineers presented several green infrastructure solutions designed to enhance urban resilience and protect water quality, directly supporting SDG 6, SDG 11, and SDG 13 (Climate Action).

• Residential Sediment Removal Drywells: These are belowground systems that collect stormwater and allow it to infiltrate slowly into the ground. A single drywell is estimated to remove 345 pounds of sediment over a 30-year period.
• Receiving Pervious Areas: These are vegetated areas designed to absorb and filter runoff from impervious surfaces, allowing sediments to settle and reducing pollutant loads.
• Rain Gardens and Permeable Pavements: Nature-based solutions that integrate water infiltration into landscaping and paved areas, which helps manage runoff and contributes to urban climate resilience.

3.2 Projected Environmental Impact

The implementation of these measures carries significant potential for environmental improvement. A city staff report projected that if every residential lot under 3,000 square feet in Aspen were to treat its stormwater, approximately 15,000 pounds of excess sediment and associated pollutants would be prevented from entering the Roaring Fork River each year. This outcome would represent a substantial contribution to achieving Target 6.3 of the SDGs (improving water quality) and protecting aquatic life as outlined in SDG 14.

4.0 Conclusion and Future Directives

The City Council did not reach a final decision on the proposed updates. Council directed staff to conduct further investigation into the practical implementation of the various stormwater systems. The discussion is set to be revisited in the following year. This ongoing process includes updating the URMP’s technical components, such as rainfall and mudflow data, to ensure the plan remains a robust tool for advancing Aspen’s commitment to sustainable urban development and its alignment with global sustainability goals.

Sustainable Development Goals (SDGs) Addressed in the Article

SDG 6: Clean Water and Sanitation

• The article’s central theme is the effort to “reduce pollutants from entering the river via stormwater.” This directly addresses the goal of ensuring the availability and sustainable management of water and sanitation for all, with a specific focus on improving water quality.

SDG 11: Sustainable Cities and Communities

• The discussion revolves around Aspen’s “Urban Runoff Management Plan” and infrastructure requirements for development projects. This relates to making cities and human settlements inclusive, safe, resilient, and sustainable by managing the environmental impact of urban development. The article also mentions measures to “reduce flood risk,” which aligns with making cities more resilient to water-related disasters.

SDG 14: Life Below Water

• By aiming to prevent “sediment and pollutant load flowing into the Roaring Fork River,” the article discusses actions that reduce land-based pollution. Since river systems ultimately flow into oceans, controlling pollution at the source is crucial for preventing marine pollution and protecting marine ecosystems.

SDG 15: Life on Land

• The initiative is designed to protect the Roaring Fork River, which is an inland freshwater ecosystem. The article highlights the importance of “protecting the natural environment from pollutants,” which is fundamental to conserving and restoring terrestrial and inland freshwater ecosystems.

Specific SDG Targets Identified

Targets under SDG 6

• Target 6.3: By 2030, improve water quality by reducing pollution. The entire proposed update to the Urban Runoff Management Plan is designed to “reduce pollutants from entering the river” and stop “excess sediment and associated pollutants” from contaminating the Roaring Fork River.
• Target 6.6: By 2020, protect and restore water-related ecosystems. The article’s focus on preventing pollution in the Roaring Fork River is a direct action to protect a specific water-related ecosystem.

Targets under SDG 11

• Target 11.5: By 2030, significantly reduce the number of deaths and the number of people affected… by disasters, including water-related disasters. The article explicitly mentions that the suggested stormwater control measures aim to “reduce flood risk.”
• Target 11.6: By 2030, reduce the adverse per capita environmental impact of cities. The city of Aspen is actively debating policies (the Urban Runoff Management Plan) to manage the environmental consequences of urban development, specifically the impact of stormwater runoff on the local river.

Targets under SDG 14

• Target 14.1: By 2025, prevent and significantly reduce marine pollution of all kinds, in particular from land-based activities. The effort to control urban stormwater runoff is a measure to mitigate a land-based activity that contributes to water pollution, which eventually affects marine environments.

Targets under SDG 15

• Target 15.1: By 2020, ensure the conservation, restoration and sustainable use of terrestrial and inland freshwater ecosystems. The plan to manage runoff directly supports the conservation of the Roaring Fork River, an inland freshwater ecosystem.

Indicators for Measuring Progress

Indicators for Target 6.3 (Improve water quality)

• Implied Indicator: Volume of pollutants and sediment prevented from entering the river. The article provides specific quantifiable data that can be used as an indicator. It states that if the plan is adopted for all small lots, “approximately 15,000 (pounds) of excess sediment and associated pollutants would be stopped from entering the river every year.” It also notes that a single “drywell can remove 345 pounds of sediment from stormwater” over 30 years.

Indicators for Target 11.6 (Reduce adverse environmental impact of cities)

• Implied Indicator: Implementation and scope of an Urban Runoff Management Plan. The article’s entire discussion is about updating and enforcing this plan. The specific thresholds mentioned (e.g., “interior remodel is greater than 50% of the total building footprint”) and the types of required infrastructure (drywells, permeable pavements) serve as indicators of the city’s commitment to managing its environmental impact.

Indicators for Target 15.1 (Conservation of freshwater ecosystems)

• Implied Indicator: Number of properties implementing stormwater treatment systems. The article suggests that progress can be measured by the adoption of technologies like drywells and pervious areas. The statement, “If every lot under 3,000 square feet in the city of Aspen treated stormwater,” implies that the number or percentage of lots with such systems is a key metric for achieving the goal of protecting the river.

SDGs, Targets, and Indicators Analysis

Source: aspentimes.com