HomeMy WebLinkAbout190827_PolicyTradeoffsThe CITY of
EDINA
Policy and Planning Trade-offs
Flood Risk Reduction Strategy
August 2019
“Floods are ‘acts of God’, but flood losses are largely acts of man.”
The CITY of
EDINA
www.EdinaMN.gov 2
Tradeoffs with regulation
Regulation Efficiency Flexibility Equity
Regulation Efficiency Flexibility Equity
The CITY of
EDINACommon flood policy objectives
Resilience
(risk reduction)
www.EdinaMN.gov 3
Efficiency
(benefits exceed cost)
Legitimacy
(political, public support)
Capacity to resist flooding
to prevent adverse impacts
Capacity to absorb and
recover quickly from a
flood-related stress
Capacity to adapt and
transform in response to
flood impacts, flexibility
Avoiding overlap between
levels of government
Lower Cost benefit ratios
are prioritized (Pareto
efficiency)
Avoiding instruments that
require significant human or
administrative resources to
operate/implement
Degree of support from
elected officials, community
Extent to which benefits
and burdens are fairly
distributed
Instrument should align
with other policy objectives
The CITY of
EDINA
www.EdinaMN.gov 4
Decision-making,
policy, and planning
The CITY of
EDINARelated/Existing City Policies
The following policies of the City of Edina provide language targeted
toward flood reduction.
•Stormwater Pollution Prevention Plan
•Street Sweeping Plan (no longer active, but some good language)
•Living Streets policy
•Draft Comprehensive Plan
•Comprehensive Water Resources Management Plan
•Floodplain Development & Floodplain Overlay Ordinances
www.EdinaMN.gov 5
The CITY of
EDINA
www.EdinaMN.gov 6
Common municipal policy mechanisms
Land use regulation
Development conditions
Green infrastructure
Stakeholder engagement/risk
communication
Flood mapping
Flood warning system
Flood hazard disclosure
Corrective tax
Stormwater charge
Subsidies
Credits
Compassionate grants
Property buyouts
Special surcharge
The CITY of
EDINAFlood Risk Management Objectives
Resilience
(risk reduction)
www.EdinaMN.gov 7
Efficiency
(benefits exceed cost)
Legitimacy
(political, public support)
Capacity to resist flooding
to prevent adverse impacts
Capacity to absorb and
recover quickly from a
flood-related stress
Capacity to adapt and
transform in response to
flood impacts, flexibility
Avoiding overlap between
levels of government
Lower Cost benefit ratios
are prioritized (Pareto
efficiency)
Avoiding instruments that
require significant human or
administrative resources to
operate/implement
Degree of support from
elected officials, community
Extent to which benefits
and burdens are fairly
distributed
Instrument should align
with other policy objectives
https://issuu.com/cigi/docs/pb_no.147web
The CITY of
EDINA
8
Green infrastructure/
low impact development
Low impact development practice Flood protection Clean water Cost efficiency Sustainability indicators
Impervious cover reduction High Medium Very high/savings Reduced materials and energy, reduced heat island effect
Soil/turf/trees Medium Low High Reduced heat island effect, wildlife habitat, reduced energy, reduced noise
Bio-retention/Rain gardens Medium Medium Medium Reduced heat island effect, wildlife habitat, reduced energy, increased maintenance burden
Pervious pavements Medium Medium Very low Reduced heat island effect, wildlife habitat, reduced energy, increased maintenance burden
Undergroundsediment/infiltration Low Medium Low Reduced heat island effect, increased maintenance burden, reduced land use
Swales, filters/other Low Medium Medium Reduced land use, increased materials, reduced energy and maintenance burden
Natural area creation, protection, restoration High High Very high/savings Provides wildlife habitat, reduced heat island effect
Regional ponds and wetlands High Medium Medium Increased wildlife habitat, increased species diversity, reduced erosion, reduced maintenance burden/emissions
Pollution prevention Low High Very high Materials and waste control, increased recycling and reuse materials, regional material preference, reduced soil hauling
The CITY of
EDINADevelopment Conditions:
Floodplain Development & Flood Insurance (FEMA)
www.EdinaMN.gov 9
•Reliance on local enforcement/loopholes/variances
•Equity concerns
•FEMA modeling is sometimes inaccurate
Weaknesses
•FEMA provides base-line protection to structures
located in the floodplain
•Applies to all new development and many
retrofit/redevelopment.
•Coordinates well with other building codes and
inspection requirements
•Reduce solar heat gain and provide green space
Strengths
In order to receive affordable flood insurance, communities must adopt and enforce floodplain
development standards. Edina has a Floodplain Development ordinance which guides development
within the 1% annual chance floodplain provided by FEMA. See Edina’s floodplain ordinance.
The CITY of
EDINAHard Cover Requirements
www.EdinaMN.gov 10
•Not very effective for large events (see Barr
modeling)
•Can be political, impacts property owners
who can afford certain amenities
•Imperviousness is challenging to measure on
a lot-by-lot basis
•Requires political buy-in, staff enforcement
Weaknesses
•Effective at reducing on-site runoff, especially
for smaller small events
•Improve longevity of storm sewer
infrastructure
•Flexible by land use
•Exceeding limits/seeking variance can trigger
additional requirements, secondary benefits
Strengths
Hard cover requirements are often incorporated into existing city policies (zoning, building
requirements, floodplain regulations, etc.). Edina’s Planning Commission is currently reviewing
options for hard cover regulations.
The CITY of
EDINALand Use Planning & Zoning
www.EdinaMN.gov 11
•Additional requirements/costs to developers may
get passed along to residents
•Enforcement for existing nonconformities
•Requires technical mapping of hazard area
•Requires zoning amendment, political
Weaknesses
•Prohibits dangerous uses in new developments
•Avoids negotiating flooding issues on a case-by-
case basis.
•Can be implemented in concert with
comprehensive planning/existing zoning regulations
•Relatively easy to maintain over time.
Strengths
Municipalities may impose restrictions within their zoning code to encourage or discourage certain
land uses within sensitive areas. Zoning mechanisms include the creation of floodplain districts,
setbacks, overlay districts, hard cover limitations, density/elevation requirements, etc.
Note: Floodplain overlay district to apply area-specific standards and/or conditions in flood-
prone localities. These can provide requirements for setbacks from a resource, stormwater
management, imperviousness, size of development, land use, etc.
The CITY of
EDINASecondary benefits
to flood policies
www.EdinaMN.gov 12
Note: These benefits
specifically refer to
imperviousness
requirements, but are
also applicable to
many other policies
that reduce flood risk
at the city level.