Preparing Stormwater Systems for Climate Change October 10 th, 2013 Monroe, MI. Leslie Yetka, Education Manager

Transcription

1 Preparing Stormwater Systems for Climate Change October 10 th, 2013 Monroe, MI Leslie Yetka, Education Manager

2 National Climate Assessment Report 2013

3 Duluth, MN June, 2012 Rainfall: ~9-14 /24 hrs Damage Total: $108 million

4 Rainfall: /24 hrs state record Damage Total: $27 million in property and crop damage

5 Rainfall: ~10 /8 hrs Damage Total: $30 million

6 Heavy Precipitation Trends Percentage increase in very heavy precipitation (heaviest of 1% of all events) from Karl et al. 2011

7 National Climate Assessment Report /11/2013

8 Provide local communities an adaptation framework to address changes in precipitation patterns and land use. Duluth - MN Sea Grant

9 1. Is the frequency and intensity of rain events likely to change in the Twin Cities area? 2. Will existing stormwater infrastructure be sufficient to manage future precipitation changes and land use changes? If not, to what degree is flooding expected to increase? 3. What are the available options to adapt stormwater infrastructure to manage predicted precipitation and land use changes? What are the costs of these options? 4. What are the best ways to engage local communities to support adaptation planning?

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11 DATA Input Outputs Historical Climatic Data Precipitation Evapotranspiration Precipitation Scenarios Global Circulation Models Down-Scaling Current Land Characteristics Soils, Water Bodies Parks /Protected Land Projected Land Characteristics Impervious Surfaces Green Infrastructure Modeling Run-off / Peak Flow Calculations EPA-SWMM Calibration Projected Precipitation Amounts Optimistic - Pessimistic System Components Adequacy Current Projected Projected Pipe Sizing Impact of Green Infrastructure Extent of Mitigation Pipe Configuration Minneapolis (Hiawatha basin) Victoria Projected Cost Impacts

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13 CMIP5 CCSM4 9-grid rcp % 5.82 CMIP3 PCM 9-grid A1b % 6.69 CMIP5 CM3 6-grid rcp % 6.33 CMIP5 CCSM4 9-grid rcp % 6.09 CMIP3 cm2.1 4-grid A1b % 6.16 CMIP5 CCSM4 9-grid rcp % 6.06 CMIP5 CM3 9-grid rcp % 7.29 CMIP3 cm2.1 9-grid A1b % 7.53 CMIP3 cm2.1 6-grid A1fi % 7.10 CMIP3 cm2.1 4-grid A1fi % CMIP3 cm2.1 9-grid A1fi % 7.08 CMIP3 cm2.1 6-grid A1b % 6.16 CMIP5 CM3 9-grid rcp % 7.88 CMIP5 CM3 6-grid rcp % 7.67 Modeled Downscaled Climate Precipitation Projections (mid-century) Generation: Model: Grid_size: Scenario: Most Likely % Increase over Historical +95% CI Historical NCDC Station Recent %

14 Projected Precipitation Amounts and Frequency: Current and Future inches/24 hrs Recent Optimistic Scenario Moderate Scenario Pessimistic Scenario Return Period (years)

15 Projected Precipitation Amounts and Frequency: Current and Future Return period (years) Recent climate mid-21st cent. Optimistic mid-21st cent. Moderate mid-21st cent. Pessimistic Design Storm % +70% +157%

16 Recent Storms Moderate Projection Pessimistic Projection City of Minneapolis Lake Hiawatha Pipeshed

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18 Hiawatha Flood Volumes Flood Volume (MG) Precip. Scenario (in) Total Street Storage Over-curb

19 Stay the course Increase Pipe Size Flood reduction projects Infiltration-based practices (LID) Protect open space and existing green infrastructure

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23 1 Bancroft Meadows Flood Basin Built 1989 (Bloomington and 42 nd )

24 Hiawatha : Dry Basin Cost Estimates for Post-Piping Upgrade Volumes Precipitation Flooding Over Curb Flooding low high (inches) (Mgal) (Mgal) acrefeet costs costs $ 554,373 $ 2,600, $ 831,582 $ 4,142, $ 1,257,860 $ 6,659,056

25 152,000 ft 3 underground 37 th Avenue Greenway Flood Project 2011

26 Hiawatha : Underground Storage Cost Estimates for Post-Piping Upgrade Volumes Precipitation Flooding Over Curb Flooding Over Curb Flooding Underground Basin # of projects comparable (Mgal) (Mgal) acre-feet costs to 37th ave $ 20,200, $ 40, 400, $ 90,088,989 34

27 LID: Reduction in Impervious Connectivity - Hiawatha Pipeshed: Impact on over-curb flooding Precipitation (inches) Existing Overcurb flooding (MG) Over-curb + BRC 1-in 10% Over-curb + BRC 1-in 15% Over-curb + BRC 1-in 20% Flood Vol. Flood Vol. Flood Vol. (MG) (MG) (MG) % Change, Existing Over Curb % Change, Existing Over Curb % Change, Existing Over Curb % % % % % % % % % % % % % % % % % % % % %

28 Total Flood Volume (million gallons) City of Victoria: Flood Volume With and Without Build-out Precip Depth (in) Existing L/U Build-Out

29 City of Victoria Recent Storms in 24 hrs

30 City of Victoria Moderate Projection in 24 hrs Increased flooding in some existing ponds Some street flooding expected Increased flooding in low lying areas

31 City of Victoria Pessimistic Projection in 24 hrs Many ponds overtopped More streets flooded Significant flooding in recreational areas

32 City of Victoria Plans and Policies: Looking Ahead and Looking Back Key policies that increased resilience: Shoreland Ordinance Wetlands and Buffer in Outlots Park Dedication Woodland Protection/Preservation Stormwater Management

33 City of Victoria Plans and Policies: Looking Ahead and Looking Back Partially developed: Schutz Lake Lake Zumbra Kelzer Pond Shoreland Ordinance Fully developed: Lake Minnetonka Lake Virginia Undeveloped: Stone Lake Lake Tamarack Stieger Lake Church Lake Carl Krey Lake Lake Wassermann Lake Auburn

34 City of Victoria Plans and Policies: Looking Ahead and Looking Back Wetlands and Buffers

35 City of Victoria Plans and Policies: Looking Ahead and Looking Back Stormwater Management

36 City of Victoria Options for Adaptation 10-yr Event Flood Volume Increase Undersized Pipes Reduce Street Flooding Create Flood Storage 50% LID Impact on Undersized Pipes * MG Ft of Pipe After pipe upsizing (MG) Cost Excess Street (MG) Cost Pipes Filled Flooding MG Cost % ,199-75% $205, ,132-30% $775, $0 0 $0-27% 0 -- $150,000- $575,000 $1,015,000- $2,350,000-9% -19% -- -9% -3% -- *LID does not provide effective flood control during large storm events

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38 Study Goal: Provide local communities an adaptation framework to address changes in precipitation and land use. How did we do this? Collaborative Approach: Collaborative planning that was informed by science and led through a participatory stakeholder process.

39 Improve quality Drawing on local knowledge to improve decision making. Using a public process that Identifies values, interests, and concerns of all who are interested in or might be affected by the process or decisions Uses the best available knowledge Incorporates new information, methods, and concerns

40 Improve legitimacy Fostering legitimate and equitable decision-making by A process that is seen by the interested and affected parties as fair and competent A process that follows the governing laws and regulations Doesn t necessarily mean everyone agrees

41 Improve capacity By increasing resilience, adaptive capacity, and social capital by Engaging the public with vetted data on severe weather trends and best available climate change science Fostering inter-town/region/watershed wide understanding, trust, and collaboration to increase resilience to stormwater risks Developing widely shared understanding of the issues and decision challenges

42 1. Convening 2. Assessing 3. Visioning and Objectives 4. I.D. Barriers Model we used for collaborative planning Outputs (what is likely to result from this step?) 5. Strategies 6. Partners & Resources May be iterative Inputs (considerations prior to moving into this phase) 7. Action Plan 8. Leadership Team 9. Actions Gruber, J Feedback & Base of Support

43 1. Convene community leaders and a broad list of stakeholders Inputs 1. Convening Outputs Input example: clear ground rules Output example: greater trust across stakeholder groups Convened a broad cross-section of stakeholders that included representatives of: Education/Academic Organizations Local Officials Federal Government Municipal Employees NGO/Conservation Orgs. Private Citizens/ Public Regional official State Agencies Staff State Officials Students Regional official 4% Students 2% State Agencies Staff 7% Private Citizens/General Public 9% Who was present? State Officials 11% Private Sector 18% Local Officials 28% Education/Acad. Organizations 4% NGO/Conservation Organizations 11% Federal Government 4% Municipal Employees 2%

44 2. Assessing the situation and affiliated problems Inputs 2. Assessing Outputs Input example: broad cross-section of public participating Output example: shared understanding of challenges and systems that need to be addressed Assessment included research by a science/technical team and discussions during the stakeholder sessions. The goal was to: Collect and analyze essential data Science/technical team Document current conditions Science/technical team and stakeholders Include diverse views and perspectives in small and large group discussions Provide an opportunity to reflect on the situation Help participants understand the underlying causes or problems

45 For example: guiding questions In what ways have you observed or heard about landuse/development and changing weather patterns impacting this region? Do you think some of these impacts might reoccur? What are the underlying causes and/or problems? Top reasons why these impacts might reoccur? Participants then voted (with dots) on the top reasons. Results were then grouped into four categories for future Working Groups.

46 3. Visioning opportunities and articulating objectives Inputs 3. Visioning & Objectives Outputs From the previous assessment process 1. Priority areas were identified 2. What could be done? 3-5 objectives identified for each priority area Work Groups: A. Education, Outreach, and Stakeholder Engagement B. Land Use Planning and Policy C. Stormwater Infrastructure (Green/Grey) and LID D. Sustainable Funding: Stormwater Infrastructure

47 Education, outreach objectives. What could be done? Identify strategies to increase stakeholder awareness, level of interest, and ownership of stormwater mgmt issues Identify strategies to educate local policy-makers about stormwater vulnerabilities, long term needs, and adaptation options Identify strategies to inform developers of alternative stormwater methods and techniques Foster consensus and cooperation among stakeholders for adaptation planning

48 4. Identification of barriers preventing progress (economic, social, cultural, political, etc. ) Inputs 4. Identification of Barriers Outputs Barriers/challenges are financial, political, social, cultural, logistical, and/or philosophical difficulties that get in the way of accomplishing the objective.

49 Objective: Identify strategies to educate local policy-makers Barriers/Challenges 1) Lack of knowledge of connections between individual actions and cumulative problem. 2) Unclear how problems can be solved and what actions there should be? 3). Potential Approaches to Resolve Barriers/Challenges 1) Educate city councils and staff 2) Use successes of existing unified groups (eg. AIS) and adopt that model 3) Recommend new standards or specific actions leaders should take 4)

50 5. Identification of strategies that recognize barriers and overall objectives Inputs high 5. Strategies Outputs Prioritizing strategies and tools for implementation Assessing impact vs. feasibility of each alternative FEASIBILITY med low low med high IMPACT

51 6. Identification and engagement of potential partners and types of resources required Inputs 6. Partners & Resources Outputs Identifying and forming potential: PPP (public-private partnerships) PPCP (public-private-community partnerships) Other governmental partnerships Etc.

52 7. Formulating action plans based on data and social values Inputs 7. Action Plan Outputs How to Proceed Action steps Responsible parties Timelines Resources available/needed

53 Action Items: 1) Identify audience: local decision makers, commissioners, volunteers Assess/Prioritize vulnerabilities 2) Convene a focus group of audience. What draws them? Will draw them? Needs assessment of targeted audience. 3) Frame the summit Develop learning objectives with: 1) Planning team 2) Include participants in planning summit 4). Sample Action Plan: Education, Outreach, Stakeholder Engagement Objective: Identifying strategies to educate local policy makers about stormwater vulnerabilities, long term needs, and options Timeline: Not identified Responsible Parties: Minnehaha Creek Watershed District, UMN Extension, Water Resources Center, Freshwater Society, Local Leaders, NOAA, MN Sea Grant Project: Convene a summit to educate local policy makers about creating resilient stormwater management systems.

54 8. Formalizing inclusive implementation leadership team Inputs 8. Leadership Team Outputs Others..

55 9. Initiating actions based on priorities, balancing highest return with feasibility of achieving results Inputs 9. Actions Outputs

56 10.Embracing open and dynamic feedback on process and actions taken. Inputs 10. Feedback and Base of Support Outputs Continue to build broad base of support...

57 Types of Positive Responses Gaining consensus on issues/impacts. Great conversation! Comments from diverse stakeholders, not just technical professionals, is important. I also like how we got to help shape future efforts. The exercise brought up different perspectives on the issues of stormwater management.

58 Types of Concerns or Proposed Changes Include people from where the problem is coming from (agriculture, development, big-box stores). Pre-release topics to be discussed so participants can come with suggestions. Well, none really this is just the start of a long journey. Invite less engineers.

59 Project team and partners This study was funded through a grant from the National Oceanic Atmospheric Administration SARP program. 10/11/2013

60 Questions?