Strategic Stormwater Solutions for Transit-Oriented Development
This is a good example of:Planning stormwater management for high density, transit oriented development
Beginning in 2014, a new 11 mile, Light Rail line (the Green Line) will connect the downtowns of Saint Paul and Minneapolis in Minnesota (the Twin Cities).
This study, nested a larger corridor planning effort, provides a stormwater management framework for the implementation of SSGI (Shared, Stacked Green Infrastructure). SSGI is a system in which stormwater runoff generated from multiple parcels is jointly treated in shared green infrastructure.
Problem: Stormwater regulations often stand in the way of great placemaking and district design by requiring Best Management Practices (BMPs) on a parcel by parcel basis. In dense urban areas, this can be difficult due to land values and space constraints. All too often, underground tanks hold and release water rather than putting rainwater to use in landscapes.
Premise: Develop strategic infrastructure solutions that are fair, equitable, and provide mutual benefit to all parties involved. This includes sharing facilities among parcels in ways that deliver multiple benefits to the community and landowners.
Stakeholders: Work off of existing relationships developed for the transit line.
The study was organized into the following four phases:
1. Set the Foundation – in the first phase, the team formed a Stakeholder Advisory Group, identified potential SSGI implementation barriers, explored public Right-of-Way considerations, convened a developers focus group, and defined governmental authority & existing stormwater regulations.
2. Explore Opportunities – Once the team scoped existing conditions, they embarked on a literature review, local examples, and how to integrate with public art (St. Paul has a public art ordinance).
3. Evaluate and Select Options – Next, the team identified potential redevelopment sites, narrowed down feasible approaches, and tested two pilot sites.
4. Work through the Details: The team adopted the following implementation sequence:
- Adopt policy resolutions authorizing feasibility studies and a SSGI program
- Pilot projects – identify several pilots for the purpose of testing and refining the SSGI implementation framework.
- Revise regulatory framework
- Institute into Agency Processes – integrate SSGI within individual redevelopment sites as well as larger projects such as Street reconstruction project, new public facilities, and small area master plans.
- SSGI projects are typically described in four parts: How stormwater is shared, the stacked functions (stormwater, economic, other environmental and social), integration of public art and any additional considerations
- Funding and on-going maintenance – Funding comes in three stages: planning, initial construction and on-going maintenance. Financing arrangements for shared systems emphasize use of development agreements, license agreements or similar formal tools to address financial and legal arrangements. These tools establish acceptable requirements, fees, noncompliance recourse, timing and other practicalities including long term responsibilities and liability. To be successful, fees, responsibilities and liability must run with the land (i.e. be included in any transfers and sales). As a practical matter, license agreements should first be executed to formalize these arrangements, and then be incorporated as an exhibit to a development agreement.
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