MIQG2022_Interactive.pdf

MICHIGAN QUICK GUIDE

F LOODPLA IN MANAGEMENT IN M ICH IGAN

www.mi.gov/floodplainmanagement

F LOODPLA IN MANAGEMENT IN M ICH IGAN

http://www.mi.gov/floodplainmanagement

MICHIGAN QUICK GUIDE I

Table of Contents

1 ........... About This Guide 2 ........... Why Do We Regulate the Floodplain?

3 ........... What is the National Flood Insurance Program (NFIP)?

4 ........... Community Responsibilities 5 ........... NFIP Recommended Planning Considerations 6 ........... Flood Insurance: Property Owner’s Financial Protection 7 ........... The NFIP’s Community Rating System (CRS)

FLOODPLAINS AND FLOOD MAPS

8 ........... Looking for FEMA Flood Map Information?

9 ........... FIRMette: FEMA Flood Maps Online 10 ......... Understanding the Riverine Floodplain 11 ......... Understanding the Regulatory Floodway 12 ......... Flood Insurance Rate Map (Riverine) 13 ......... Approximate Flood Zones 14 ......... Using the Riverine Flood Profile to Determine Riverine BFEs 15 ......... Floodway Data Table 16 ......... Old Format Flood Insurance Rate Map 17 ......... Old Format Flood Boundary and Floodway Map 18 ......... Understanding the Coastal Floodplain 19 ......... Flood Insurance Rate Map (Great Lakes) 20 ......... Are Building Sites Higher than the BFE?

21 ......... Options to Document Structures are Not in SFHAs

22 ......... FIRM Revisions: LOMAs and LOMR-Fs 23 ......... LOMAs: “Out as Shown” 24 ......... More on LOMAs: Basements and Decks 25 ......... FIRM Revisions: CLOMRs and LOMRs 26 ......... Levee Certification for FIRMs

CONSIDERATIONS FOR SITING DEVELOPMENT

27 ......... Activities in SFHAs that Require Local Permits and ............. Approvals 28 ......... Avoid SFHAs When Possible 29 ......... Fill Can Adversely Affect Floodplain Functions 30 ......... The Floodway “No-Rise” Certification

PLANNING DEVELOPMENT AND BUILDINGS

31 ......... Floods Don't Always Stop at the BFE 32 ......... Freeboard: Build Higher, Reduce Damage, Save on ............. Insurance 33 ......... Fundamentals of Flood Resistant Construction 34 ......... Michigan Construction Code Includes Flood Requirements

APPLICATIONS AND ELEVATION CERTIFICATES

35 ......... Carefully Complete the Permit Application 36 ......... Some Key Floodplain Development Permit Review Steps 37 ......... Communities Must Retain Flood Records Permanently 38 ......... What is the Elevation Certificate and How is it Used?

MICHIGAN QUICK GUIDE II

39 ......... Completing the Elevation Certificate 40 ......... Paperwork is Important

FLOOD ZONE A/AE: BUILDING REQUIREMENTS

41 ......... How to Elevate Buildings in Flood Zone A/AE 42 ......... Placement and Compaction of Fill in Zone A/AE 43 ......... Basements in Flood Zones Are Unsafe 44 ......... Enclosures and Crawlspace Details (Zone A/AE) 45 ......... Utility Service, Equipment, and Tanks 46 ......... Accessory Structures 47 ......... Recreational Vehicles

FLOOD ZONE V: BUILDING REQUIREMENTS

48 ......... General Requirements in Coastal High Hazard Areas ..............(Zone V) 49 ......... How to Elevate Buildings in Flood Zone V 50 ......... The Zone V Design Certificate 51 ......... Enclosures Below Zone V and CAZ Buildings

EXISTING BUILDINGS

52 ......... Improvements and Repairs of Buildings in Flood Zones 53 ......... What is Meant by Pre-FIRM and Post-FIRM?

54 ......... Substantial Improvement/Substantial Damage Desk ............. Reference

55 ......... Answers to Questions about Substantial Improvement and ............. Substantial Damage 56 ......... Estimating Costs of Improvements and Repairs 57 ......... Estimating Substantial Damage 58 ......... Non-Substantial Improvements Other than Additions 59 ......... Substantial Improvement: Renovation Only 60 ......... Lateral Addition Only 61 ......... Substantial Improvement: Addition Plus Other Work 62 ......... Repair of Damaged Buildings 63 ......... Elevating an Existing Building 64 ......... Paying for Post-Flood Compliance

FLOOD PROTECTION AND MITIGATION

65 ......... Some Flood Protection for Older Homes is Easy and Low Cost 66 ......... Some Flood Mitigation Projects are More Costly Up Front

SAFETY AND PREPAREDENSS

67 ......... Be Prepared for Flood Emergencies 68 ......... Turn Around Don't Drown®

RESOURCES

69 ......... Useful Resources and Common Acronyms 70 ......... Want to Learn More?

Table of Contents (continued)

MICHIGAN QUICK GUIDE 1

This Quick Guide helps local officials and citizens understand why and how Michigan communities must manage development in floodplains to protect people and property. Flood-prone communities adopt codes and ordinances that detail the rules and requirements. In cases of conflict, those codes and ordinances, not the guidance provided in this publication, must be followed.

This Quick Guide was developed and funded jointly by the Michigan Department of Environment, Great Lakes, and Energy (EGLE) and the Federal Emergency Management Agency (FEMA). Download the Quick Guide from www.michigan.gov/floodplainmanagement.

Questions, comments and requests for additional copies should be directed to the State NFIP Coordinator at occhipintim@michigan.gov.

About This Guide

Prepared by:

For more detail on all aspects of floodplain management, please refer to FEMA 480, National Flood Insurance Program, Floodplain Management Requirements: A Study Guide and Desk Reference for Local Officials.

http://www.michigan.gov/floodplainmanagement mailto:occhipintim@michigan.gov

MICHIGAN QUICK GUIDE 2

Why Do We Regulate the Floodplain?

To protect people and property. Implementing floodplain management regulations reduces vulnerability to future flood risk. If we know low lying land will flood from time to time, we should make reasonable decisions to help protect our families, homes, and businesses.

To make sure National Flood Insurance Program (NFIP) flood insurance is available.

Communities must join the NFIP and administer floodplain management requirements before residents and businesses can purchase NFIP flood insurance and be eligible for some types of Federal assistance, including flood mitigation grants.

To save tax dollars. Every time communities experience flood disasters local budgets are impacted. If we build smart, we’ll have fewer problems the next time the water rises. Remember, Federal disaster assistance is not available for all floods. Even when the President declares a disaster, communities still must pay a portion of repair and clean-up costs, temporary housing assistance, and evacuation expenses.

To avoid liability and lawsuits. If we know an area is mapped as a flood hazard area, and if we know people could be in danger and buildings could be damaged, doesn’t it make sense to take reasonable protective steps as our communities develop and redevelop?

Since 1978, NFIP flood insurance policy holders in Michigan have received over $134 million in claim payments. Even though that represents many payments, most of the State’s flood-prone property owners do not have flood insurance.

MICHIGAN QUICK GUIDE 3

The National Flood Insurance Program (NFIP) was created by Congress in 1968 to protect lives and property and to reduce the financial burden of providing disaster assistance. The NFIP is administered by the Federal Emergency Management Agency (FEMA). Nationwide, over 22,300 communities participate in the NFIP. In Michigan, more than 1,000 counties, cities, townships and villages participate.

The NFIP is based on a mutual agreement between the Federal Government and communities. Communities that participate agree to regulate development in mapped flood hazard areas according to certain criteria and standards. The partnership involves:

n Flood hazard maps. In partnership with communities and the State, FEMA produces flood maps in accordance with FEMA standards. The maps are used by communities, insurance agents, real estate professionals, and others.

n Flood insurance. Property owners and renters in participating communities are eligible to purchase NFIP flood insurance for buildings and contents.

n Regulations. Communities must adopt and enforce minimum floodplain management regulations so that development, including buildings, is undertaken in ways that reduce exposure to flooding.

What is the National Flood Insurance Program (NFIP)?

To learn more about the NFIP, including your potential flood risk and the approximate cost of a flood insurance policy, go to FEMA’s FloodSmart website www.floodsmart.gov.

http://www.floodsmart.gov

MICHIGAN QUICK GUIDE 4

To participate in the National Flood Insurance Program, Michigan communities agree to:

n Recognize flood hazards in community planning (see page 5) n Adopt and enforce flood maps and a flood damage prevention ordinance n Require permits for all types of development in the floodplain (see page 27) n Assure that building sites are reasonably safe from flooding n Require new and substantially improved homes, manufactured homes, and additions to be elevated to or above the Base Flood Elevation (BFE) plus 1 foot n Require non-residential buildings to be elevated or dry floodproofed to or above the BFE plus 1 foot n Determine if damaged buildings are substantially damaged n Conduct field inspections; cite and remedy violations n Require and maintain surveyed elevation information to document compliance (see pages 38, 39, and 40) n Carefully consider requests for variances n Resolve non-compliance and violations of floodplain management requirements n Advise and work with FEMA and the EGLE when updates to flood maps are needed n Maintain records for review and respond to periodic requests for reports from EGLE and FEMA

Community Responsibilities

MICHIGAN QUICK GUIDE 5

Michigan communities should consider incorporating planning considerations into comprehensive plans, land development codes, floodplain management regulations, and multi-hazard mitigation plans to reflect the long-term goal of increasing resiliency to future flooding. NFIP regulations (44 CFR Section 60.22(c)) outline 19 factors for consideration, including:

n Divert development to areas outside the SFHA to reduce flood damage n Full public disclosure to potential buyers of properties in the SFHA n Acknowledge that SFHA development may increase flood risk of existing development n Improve local drainage to control increased runoff that increases the probability of flooding on other properties n Require additional elevation above the minimum above the elevation required by the Michigan Construction Codes (MCC), which is the BFE plus 1 foot n Require consistency between State, regional and local comprehensive plans and floodplain management programs n Require evacuation plans for manufactured home parks and subdivisions

NFIP Recommended Planning Considerations

MICHIGAN QUICK GUIDE 6

Who needs flood insurance? Flood insurance is required for all buildings in mapped flood zones shown on FEMA’s maps if they are financed by Federally-backed loans or mortgages. All homeowners, business owners, and renters in communities that participate in the NFIP may purchase NFIP flood insurance on any building and its contents, even if outside of the mapped flood zone. Homes in mapped flood zones are five times more likely to be damaged by flooding than by major fires.

Not in a mapped flood zone? Unfortunately, it’s often after a flood that many people discover that their home or business property insurance does NOT cover flood damage. In Michigan, approximately 35% of all flood damage occurs in low risk zones, commonly described as being “outside the mapped floodplain.”

Protected by a levee or dam? Even areas protected by levees or other flood control structures have some risk of flooding if the structures are overtopped or fail. Even when levees provide “100-year” flood protection, there is still a chance that a higher flood will occur.

What about disaster grants and loans? Federal disaster grants do not cover most losses and repayment of a disaster loan can cost many times more than the cost of a flood insurance policy.

Want to know more? Learn more at www.floodsmart.gov. To purchase a policy, call your insurance agent.

Flood Insurance: Property Owner’s Financial Protection

1,000

3,200$ 1,000

3,200

Disaster Loan

TYPICAL YEARLY COSTS

Flood Insurance

MICHIGAN QUICK GUIDE 7

The NFIP’s Community Rating System (CRS)

Community officials can request assistance from CRS specialists to help with the application process and prerequisites. Check the online CRS Resource Center (see page 69).

The NFIP recognizes communities that achieve better flood resiliency by providing policy holders with reduced flood insurance premiums.

Communities must apply to participate in CRS and commit to implement and certify activities that contribute to reduced flood risk. Examples of actions communities can take to reduce the cost of flood insurance premiums include:

n Preserve open space in the floodplain n Enforce higher standards for safer development through zoning, stormwater, subdivision, and flood damage protection ordinances n Obtain grants to buy out or elevate houses, or to floodproof manufacturing/industrial structures n Develop hazard mitigation plans and watershed and storm management plans n Undertake engineering studies and prepare flood maps n Maintain drainage systems n Monitor flood conditions and issue warnings n Inform people about flood hazards, flood insurance, and how to reduce flood damage

Property owners in 21 Michigan communities that participate in the CRS receive premium discounts ranging from 5% to 25% (as of January 2022).

8 ........... Looking for FEMA Flood Map Information?

9 ........... FIRMette: FEMA Flood Maps Online 10 ......... Understanding the Riverine Floodplain 11 ......... Understanding the Regulatory Floodway 12 ......... Flood Insurance Rate Map (Riverine) 13 ......... Approximate Flood Zones 14 ......... Using the Riverine Flood Profile to Determine Riverine BFEs 15 ......... Floodway Data Table 16 ......... Old Format Flood Insurance Rate Map 17 ......... Old Format Flood Boundary and Floodway Map 18 ......... Understanding the Coastal Floodplain 19 ......... Flood Insurance Rate Map (Great Lakes) 20 ......... Are Building Sites Higher than the BFE?

21 ......... Options to Document Structures are Not in SFHAs 22 ......... FIRM Revisions: LOMAs and LOMR-Fs 23 ......... LOMAs: “Out as Shown” 24 ......... More on LOMAs: Basements and Decks 25 ......... FIRM Revisions: CLOMRs and LOMRs 26 ......... Levee Certification for FIRMs

FLOODPLAINS AND FLOOD MAPS

MICHIGAN QUICK GUIDE 8

n Flood Insurance Studies (FISs) are compilations of flood risk information used for community planning and development.

n Flood Insurance Rate Maps (FIRMs) show flood zones subject to regulations and where flood insurance is required.

n Access FIRMs at the FEMA Flood Map Service Center at https://msc.fema.gov, where current and historical flood maps may be viewed and downloaded.

n Many cities and counties also make digital flood maps available online, sometimes with property parcel data.

Looking for FEMA Flood Map Information?

Need a fast answer? Csommunity planning, zoning, engineering, or permit offices may also have paper flood maps available for viewing by the public.

https://msc.fema.gov

MICHIGAN QUICK GUIDE 9

Go to https://msc.fema.gov and check out the “MSC Frequently Asked Questions.” For step-by-step instructions on how to read flood maps and view the How to Read a Flood

Insurance Rate Map Tutorial.

Portions of flood maps can be produced, saved, and printed by making a “FIRMette.” FIRMettes are full-scale sections of FIRMs.

n For instructions, search online for “How to Print a FIRMette and Download a FIRM Panel.”

n Making a FIRMette is easy after a property is located. Use the <Search by Address> link or <Search All Products> to find the community and map panel of interest.

n Earlier versions of FIRMs are available for many communities, so current flood hazard information can be compared to historic data.

FIRMette: FEMA Flood Maps Online https://msc.fema.gov

MICHIGAN QUICK GUIDE 10

Understanding the Riverine Floodplain

For riverine floodplains with Base Flood Elevations (BFEs) determined by detailed flood studies, the Flood Profile in the Flood Insurance

Study shows water surface elevations for different frequency floods (see page 14).

The Special Flood Hazard Area (SFHA) is that portion of the floodplain subject to inundation by the base flood (1% annual chance). Riverine SFHAs are shown on FIRMs as Zones A, AE, AH, AO, AR, and A99. Older FIRMs may have Zones A1-A30.

See page 11 to learn about the floodway, the area of the SFHA where flood waters usually are deeper and flow faster.

See page 18 to learn about coastal floodplains in the Great Lakes counties.

MICHIGAN QUICK GUIDE 11

Understanding the Regulatory Floodway

For any proposed floodway development, the applicant must provide evidence that “no rise” will occur or obtain a Conditional Letter of Map Revision (CLOMR) before a local floodplain permit can be issued

(see page 25). Experienced registered professional engineers must make sure proposed projects either won’t increase flooding or that any increases do not impact structures on other properties.

The Floodway is the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to pass the base flood discharge without cumulatively increasing flood elevations.

Computer models are used to simulate “encroachment” or development in the floodway fringe in order to predict where and how much the Base Flood Elevation would increase if the floodway fringe is allowed to be developed.

MICHIGAN QUICK GUIDE 12

Flood Insurance Rate Map (Riverine)

Unshaded Zone X is all other areas considered low risk.

Base Flood Elevation (BFE) is the water surface elevation of the base flood rounded to the nearest whole foot (consult FIS profiles and tables for regulatory elevations).

The Floodway is the cross-hatched area (see page 11).

Zone AE is the 1% annual chance (100-year) floodplain with BFEs.

Cross Section location (see page 14).

Shaded Zone X is the 0.2% annual chance (500-year) floodplain.

Zone A (approximate) is the 1% annual chance floodplain.

MICHIGAN QUICK GUIDE 13

Approximate Flood Zones

Approximate Zone A designations are based on minimum criteria established FEMA, using very little field work and limited data.

Newer FIRMs have better elevation data based on high resolution topography (LiDAR) which results in more accurate boundaries.

When development is proposed in Approximate Zone A, BFEs must be determined before permit applications are reviewed. BFE estimates may be provided by EGLE.

For more information and to look up EGLE floodplain staff contacts by district, visit www.michigan.gov/ floodplainmanagement.

An Approximate Zone A is a special flood hazard area where BFE information is not provided.

Everyone lives in an area with some flood risk – it’s just a question of whether it is a low, moderate, or high-risk flood hazard area.

MICHIGAN QUICK GUIDE 14

BFE= 583BFE= 583BFE= 583

Using the Riverine Flood Profile to Determine Riverine BFEs

Flood Profiles from Flood Insurance Study reports can be used to determine the BFE at a specific site. Profiles also show estimated water surface elevations for floods other than the 1% annual chance flood (100-year).

On the effective flood map, locate the site by measuring the distance, along the profile baseline of the stream channel, from a known point such as a road or cross section, for example, or

Scale that distance on the Flood Profile and read up to the profile of interest, then across to determine the BFE, to the nearest 1/10 of a foot.

(Answer: 583.0 feet).

0.2% Annual Chance Flood

1% Annual Chance Flood

2% Annual Chance Flood

10% Annual Chance Flood

Stream Bed

Cross Section Location

MICHIGAN QUICK GUIDE 15

Floodway Data Table

Flood Insurance Studies have Floodway Data Tables for every waterway that was studied by detailed methods for which floodways were delineated.

Velocity estimates based on the mean velocity for the cross sections.

Elevations may not consider backwater effect from downstream river.

Amount of increase between without and with floodway is not more than 0.1 ft at any location.

1Feet above mouth

1 2 3

MICHIGAN QUICK GUIDE 16

FLOOD HAZARD ZONES

Zone C (or Zone X) is all areas considered to be low risk.

Zone B (or shaded Zone X) is subject to flooding by the 500-year flood (0.2% annual chance), and other moderate risk areas.

Zone A, Zones A1-A30 or Zone AE are subject to flooding by the base or 100-year flood (1%-annual-chance), and are considered high risk areas.

Base flood elevation (BFE).

Water surface elevation of the base flood at specific locations.

FEMA prepares Flood Insurance Rate Maps (FIRMs) to show areas that are at high risk of flooding.

These “old format” FIRMs, and companion Flood Boundary and Floodway Maps (see page 17), are being revised and digitized as part of FEMA’s nationwide revision initiative.

Old Format Flood Insurance Rate Map

MICHIGAN QUICK GUIDE 17

The Floodway is the white area around the waterway centerline.

Cross Section location, where ground surveys determined the shape of the land and how constrictions such as bridges and culverts affect the flow of floodwater.

Floodway maps do not show flood zones or BFEs. Check the companion FIRM for that information. Page 16 shows the FIRM that matches the map clip to the left.

FEMA prepared Floodway maps as companions to many “old format” FIRMs. You should check to see if your project will be in the Floodway because additional engineering may be required (see page 30)

Old Format Flood Boundary and Floodway Map

MICHIGAN QUICK GUIDE 18

Understanding the Coastal Floodplain

Areas subject to Coastal A Zone conditions (wave heights between 3 feet and 1.5 feet) may not be shown on FIRMs.

The Michigan Construction Code treats the CAZ area as Zone V and requires development to comply with the Zone V requirements, except backfilled stem walls are allowed.

The Coastal High Hazard Area (Zone V) is the Special Flood Hazard Area that extends from offshore to the inland limit of a primary frontal dune along an open coast and any other area subject to high velocity wave action. The area is designated on the FIRM as Zone VE.

The term Coastal A Zone (CAZ) refers to a portion of the SFHA landward of a Zone V or landward of an open coast without Zone V.

CAZs may be subject to breaking waves between 3 and 1.5 feet high.

MICHIGAN QUICK GUIDE 19

Flood Insurance Rate Map (Great Lakes)

Zone AE is subject to flooding by the base or 1% annual chance (100-year) flood, and waves less than 3 feet high.

Zone VE is where wave heights are expected to be 3 feet or more.

Base Flood Elevation (BFE) is the water surface elevation (in feet above the vertical datum shown on the map).

Shaded Zone X is the 0.2% annual chance (500-year) floodplain.

Unshaded Zone X is the area of minimal flood risk outside the 0.2% annual chance (500-year) floodplain.

MICHIGAN QUICK GUIDE 20

If land is shown on the map as “in” the SFHA, but the building site is on natural ground that is higher than the BFE, owners should get a professional surveyor to complete a FEMA Elevation Certificate (EC). Submit a request for a Letter of Map Amendment (LOMA) to FEMA along with the EC to verify that the structure is above the BFE (see page 22). If FEMA approves the request, lenders are not required to have property owners get flood insurance policies, although some may still require policies.

FEMA and EGLE encourage owners with LOMAs to get flood insurance at reduced rates.

Owners should keep certificates and LOMAs with deeds— the documentation will help future buyers.

Are Building Sites Higher than the BFE?

MICHIGAN QUICK GUIDE 21

Sometimes property owners are asked to provide evidence their buildings and structures are not in SFHAs.

n Most mortgage lenders will accept FIRMettes (see page 9) as evidence that structures are not in SFHAs.

n Lenders may require maps provided by a community, surveyor, or engineer that clearly show structures are not in SFHAs.

n Owners can ask lenders to reconsider determinations.

Documentation may be required to clearly show a structure is outside of the SFHA. Lenders may require FEMA LOMAs, especially if it is a close call.

Options to Document Structures are Not in SFHAs

Structure not in SFHA.

MICHIGAN QUICK GUIDE 22

The most accurate information available is used to make flood maps, including topographic base maps and detailed engineering methods or methods of approximation. FEMA issues map revisions if technical data are submitted to support the changes.

Letter of Map Amendment (LOMA) is an official amendment to an effective FIRM that may be issued when a property owner provides additional technical information from a professional surveyor, such as ground elevation relative to the BFE. Lenders may waive the flood insurance requirement if the LOMA removes a building site from the SFHA because natural ground at the site is at or above the BFE.

Letter of Map Revision Based on Fill (LOMR-F) is an official revision to an effective FIRM that is issued to document FEMA’s determination that a structure or parcel of land has been elevated by fill above the BFE, and therefore is no longer in the SFHA. Lenders may waive the insurance requirement if the LOMR-F removes a building site from the SFHA.

FIRM Revisions: LOMAs and LOMR-Fs

Check www.fema.gov/letter-map-amendment-letter-map-revision-based-fill-process for guidance on map revisions. Professional surveyors can submit eLOMAs through

FEMA’s web-based application for professional surveyors.

http://www.fema.gov/letter-map-amendment-letter-map-revision-based-fill-process

MICHIGAN QUICK GUIDE 23

n Mortgage lenders that are regulated or insured by the Federal Government are mandated to require flood insurance when structures are in, or touch, the SFHA.

n Lenders sometimes perform automated determinations, where computers compare parcel locations to the SFHA map.

n Owners can ask lenders to reconsider determinations. Documentation may be required to clearly show a structure is outside of the SFHA. Lenders may require FEMA LOMAs, especially if it is a close call.

n Lenders have discretion to require flood insurance even when structures are not in the SFHA (usually occurs when a portion of the lot is in the SFHA).

LOMAs: “Out as Shown”

See page 21 for documentation required for lenders or that is required to seek Letters of Map Amendment from FEMA to show structures are not in SFHAs, sometimes called “out as shown.”

Red Circle: A corner of the structure is in the SFHA. Lenders must require flood insurance unless the owner obtains a Letter of Map Amendment from

FEMA.

Yellow Circles: Structures clearly not in the SFHA, but parts of the lots may be in. (Flood insurance is not mandatory, but is encouraged.)

MICHIGAN QUICK GUIDE 24

Owners can obtain LOMAs to show buildings are not in SFHAs even when buildings have basements, provided:

n Earthen fill has not been placed since date of the first FEMA map showing the site in the SFHA.

n The Lowest Adjacent Grade (LAG) is at or above the BFE.

Owners can obtain LOMAs to show buildings are not in SFHAs when buildings have decks or stairs, provided:

n The Lowest Adjacent Grade (LAG) at the lowest deck or stair support is at or above the BFE.

n Documentation that the deck or stairs are detached (not structurally connected), as long as the LAG next to the building is at or above the BFE.

More on LOMAs: Basements and Decks

Not eligible for LOMA

MICHIGAN QUICK GUIDE 25

n Conditional Letter of Map Revision (CLOMR) comments on whether a proposed project, if built as shown on the submitted documentation, would meet the standards for a map revision. Communities should require CLOMRs before issuing permits for projects that propose to increase BFEs or change SFHA or floodway boundaries. Certificates of Occupancy/Compliance should be withheld until receipt of the final LOMR based on “as-built” documentation and certification.

n Letter of Map Revision (LOMR) is an official revision to an effective FIRM that may be issued to change flood insurance risk zones, special flood hazard areas and floodway boundary delineations, BFEs and/or other map features. Lenders may waive the insurance requirement if the approved map revision shows buildings to be outside of the SFHA.

FIRM Revisions: CLOMRs and LOMRs

State law requires LOMRs when fill and grading alter BFEs or change SFHA or floodway boundaries.

To learn more and download FEMA forms, find links by searching key words

“MT-EZ,” “MT-1,” and “MT-2.”

MICHIGAN QUICK GUIDE 26

Many levees are designed to protect land against flooding from the Base Flood. In order for FEMA to show those areas as outside of the Special Flood Hazard Area, communities and levee owners must certify that levees meet certain design criteria. Certification will present significant challenges during the map revision process.

Communities that have levees should determine as soon as possible whether certification will be required.

Pursuant to FEMA’s Procedural Memoranda 34 and 43, and as outlined in Federal regulations at 44 CFR Section 65.10, the documentation requirements address:

n Freeboard n Closures n Embankment protection for erosion n Embankment and foundation stability n Settlement n Interior drainage and seepage n Operation and maintenance plans n Other site-specific criteria and state requirements

Levee Certification for FIRMs

* Freeboard is the distance between the BFE and the top of the levee; for FEMA accreditation freeboard is usually 3 feet

27 ......... Activities in SFHAs that Require Local Permits and Approvals 28 ......... Avoid SFHAs When Possible 29 ......... Fill Can Adversely Affect Floodplain Functions 30 ......... The Floodway “No-Rise” Certification

CONSIDERATIONS FOR SITING DEVELOPMENT

MICHIGAN QUICK GUIDE 27

Floodplain development or building permits must be obtained before these activities and ANY land-disturbing activities occur in flood zones.

Contact community permitting offices for specific requirements.

Regulated activities include but are not limited to:

n Construction of new buildings n Additions to buildings n Improvements to buildings n Renovation of building interiors n Repair of damaged buildings n Placement of manufactured homes n Subdivision of land n Construction or placement of temporary buildings and accessory structures n Construction of agricultural buildings n Construction of roads, bridges, and culverts n Placement of fill, grading, excavation, mining, and dredging

Activities in SFHAs that Require Local Permits and Approvals

MICHIGAN QUICK GUIDE 28

Avoid SFHAs When Possible

Let the floodplain perform its natural function – if possible, keep it as open space. Other compatible uses:

Recreational areas, playgrounds, reforestation, unpaved parking, gardens, pasture, and created wetlands.

All land subdivided into lots, some lots partially in the floodplain, setbacks modified to keep homesites on high ground.

RECOMMENDED

Floodplain land put into public/ common open space, net density remains, lot sizes reduced and setbacks modified to keep homesites on high ground.

RECOMMENDED

All land subdivided into lots, some homesites and lots partially or entirely in the floodplain.

NOT RECOMMENDED

MICHIGAN QUICK GUIDE 29

Fill Can Adversely Affect Floodplain Functions

Floodplains are supposed to store and convey floodwater. If storage space is blocked by fill material, future flooding may be worsened. Fill may change drainage and adversely affect adjacent properties. Fill can alter valuable floodplain functions, including wildlife habitat, wetlands, and groundwater infiltration.

Some communities and the State floodplain statute require compensating excavation to offset the loss of flood storage associated with projects that propose placing fill in floodplains.

MICHIGAN QUICK GUIDE 30

P.E.

XYZ Engineering, Inc., Anytown, MI

Mr. Floodplain Manager 1000 Main Street Anytown, MI

Re: ABC Developer, Inc.

210 River Road Anytown, MI

This is to certify that I am a duly qualified professional engineer licensed to practice in the State of Michigan. It is further to certify that the attached technical data supports the fact that the described project will not impact the floodway width or 1% elevation (will not raise or lower by more than 0.00 ft.) of said flooding source in the Flood Insurance Study for the above community dated [date of FIS] and will not impact the 1% elevation at unpublished cross-sections in the vicinity of the proposed development.

The floodway encroachment analysis must be based on technical data obtained from FEMA.

Reduce flood risk – don’t build in the Floodway!

n Floodways convey the a large volume of water and may have high velocities.

n State law prohibits residential development in floodways.

n Engineers must prepare floodway encroachment analyses to evaluate the hydraulic impact of proposed development, including but not limited to grading/filling, new/replacement culverts and bridges, and bank stabilization.

n Development is allowed if certified to cause “no-rise” (0.00 ft. increase) in BFEs or if legal arrangements are made.

n Fencing in floodways should be “open” to allow floodwater to flow through; solid and chain link fencing are floodway encroachments.

n “No-rise” certifications must be signed by a Professional Engineer licensed in Michigan and qualified to conduct hydraulic analyses.

n Search online for “Michigan Hydraulic Report Guidelines” for more information about no-rise certifications and hydraulic modeling of floodway impacts.

The Floodway “No-Rise” Certification

31 ......... Floods Don't Always Stop at the BFE 32 ......... Freeboard: Build Higher, Reduce Damage, Save on Insurance 33 ......... Fundamentals of Flood Resistant Construction 34 ......... Michigan Construction Code Includes Flood Requirements

PLANNING DEVELOPMENT AND BUILDINGS

MICHIGAN QUICK GUIDE 31

CAUTION! Major storms and flash floods can cause flooding that rises higher than the Base Flood Elevation (BFE). Be safer – protect your home or business by avoiding flood zones or building higher.

See page 32 to see how this will avoid damage and may lower your NFIP flood insurance costs.

Floods Don't Always Stop at the BFE

Many people don’t understand just how risky building in flood zones can be. There is a greater than a one in four chance that a non-elevated home in the SFHA will be flooded during a 30-year mortgage period. The chance that a major fire will occur during the same period is less than one in 20!

MICHIGAN QUICK GUIDE 32

The Michigan Construction Codes require all buildings in SFHAs to have the lowest floor elevated to at least BFE plus 1 foot. Estimated savings – avoided building flood damage -- shown below for elevating one foot higher do not include costs to replace personal belongings and temporary housing costs during clean-up and repairs. Owners of buildings elevated above the BFE also save on federal flood insurance.

Remember!

Builders must submit floor elevations as part of foundation inspections. An error of just 6 or 12 inches could be costly for all future owners.

Freeboard: Build Higher, Reduce Damage, Save on Insurance

Freeboard is additional height– a factor of safety– above the BFE. Buildings that are higher than the BFE experience less flood damage.

LOWEST

FLOOR

AVOID $70,000 DAMAGE

MCC MINIMUM

+1ft.

+2ft.

Based on data from www.floodsmart.gov for 2,500 sq. ft. 1-story home http://www.floodsmart.gov

MICHIGAN QUICK GUIDE 33

In short ... flood resistant buildings!

Two objectives of the NFIP are to reduce flood damage and guide development to less hazard prone areas. When buildings are built in special flood hazard areas, increased resistance to flooding is achieved by the following fundamentals:

n Foundations capable of resisting flood loads n Lowest floors elevated at least 1 foot above the BFE (100-year floodplain) n Equipment and utilities elevated or designed to remain intact and be restored easily n Enclosures below elevated floors limited to parking, limited storage, and building access and designed to minimize damage n Flood damage-resistant materials used below elevated lowest floors

Fundamentals of Flood Resistant Construction

Critical and essential facilities such as hospitals, fire stations, police stations, and buildings where hazardous materials or critical records are stored should be located outside of the floodplain. But when they must be located in the floodplain, Michigan Building Code requires them to be elevated at least 2 feet above the BFE for more protection during extreme flooding. Facility owners should develop emergency plans for actions to take before the onset of flooding, during floods, and after floodwater recedes.

MICHIGAN QUICK GUIDE 34

Michigan Construction Code Includes Flood Requirements

View the MCC, with State amendments, at https://up.codes/codes/michigan and view FEMA’s “Highlights of ASCE 24” at www.fema.gov/emergency-managers/risk-management/building-science/building-codes/flood.

As of mid-2022, the 2015 MCC includes flood provisions that meet or exceed the NFIP requirements for buildings and structures in flood hazard areas. All counties, cities and towns are required to enforce the MCC. Some communities enforce “higher standards” than those required by the MCC.

n Michigan Building Code (MBC): Flood provisions are primarily in Section 1612 Flood Loads, which refers to the standard Flood Resistant Design and Construction (ASCE 24).

n MBC Appendix G: Floodplain management requirements in Appendix G include flood map duties, variances, and development other than buildings, including subdivisions, site improvements, floodway encroachments, watercourse alterations, manufactured homes, recreational vehicles, tanks, temporary storage and structures, and miscellaneous structures n Michigan Residential Code (MRC): Flood provisions are primarily in Section R322 Flood-Resistant Construction, although there are requirements in several other sections.

n Michigan Rehabilitation Code for Existing Buildings: Flood provisions are found in sections on repairs, alterations, additions, and historic structures and in sections on prescriptive and performance compliance methods.

n Michigan Plumbing, Mechanical, and Fuel Gas Codes: Flood provisions are in a number of sections.

https://up.codes/codes/michigan http://www.fema.gov/emergency-managers/risk-management/building-science/building-codes/flood

35 ......... Carefully Complete the Permit Application 36 ......... Some Key Floodplain Development Permit Review Steps 37 ......... Communities Must Retain Flood Records Permanently 38 ......... What is the Elevation Certificate and How is it Used?

39 ......... Completing the Elevation Certificate 40 ......... Paperwork is Important

APPLICATIONS AND ELEVATION CERTIFICATES

MICHIGAN QUICK GUIDE 35

Good information will lead to better construction and less exposure to future flood damage.

Contact the local floodplain administrator or building, planning, zoning, or engineering department for application forms and guidance.

You must get all permits before you work in a flood zone.

Carefully Complete the Permit Application

Part of Floodplain Development Permit Application (only key parts shown)

Application No.: _________________ Date Filed: _________________

Applicant: ______________________________________________________________

Type of Development: � New construction � Residence � Commercial � Multifamily � Warehouse/Industrial � Addition � Repair � Accessory Structure/Garage � Fill/Grading � Culvert/Bridge � Other (describe): _____________________________ Property located in Zone _______________ on FIRM dated: ___________________ Location is: � Floodway/Fringe not determined. � Fringe. � Floodway.

Base Flood Elevation (BFE) at site: ___________ Datum: � NAVD, 1929 Flood Protection Elevation (FPE) at site: _________ � NAVD, 1988

Approved by: ___________________ Title: _________________ Date: ________________

2022-12 David and Sally Jones

AE

802.0 804.0

Robert Reviwer Building Official

3/23/2022

12/9/2014

5/18/2022

� FILLFILLFILL

MICHIGAN QUICK GUIDE 36

Some Key Floodplain Development Permit Review Steps

The permit reviewer must check many things. Some of the key questions are:

n Is the site in the mapped flood zone or floodway?

n Is the natural ground elevation below the BFE?

n Does the site plan show the flood zone, Base Flood Elevation and building location?

n Is substantial improvement or repair of substantial damage proposed?

n Is an addition proposed?

n Will new buildings and utilities be elevated properly?

n Do the plans show an appropriate and safe foundation?

n Are all required design certifications submitted?

n Will the owner/builder have to submit an as-built Elevation Certificate?

n Have all required State and federal permits been issued before the local permit is issued?

MICHIGAN QUICK GUIDE 37

Communities that participate in the NFIP agree to maintain certain documentation for all development in flood zones, including but not limited to:

n Permits issued and variances granted n Letters of Map Change revising FIRMS (see pages 22 and 25) n Floodway encroachment and watercourse alteration n Design certifications for dry floodproofed buildings n Design certifications for engineered flood openings n Determinations of whether alterations, improvements or additions to existing buildings are substantial improvements n Determinations of whether damaged buildings are substantially damaged n “As-built” building elevations (Elevation Certificates) completed by a licensed Professional Surveyor.

Maintaining permanent records allows communities to respond to citizen inquiries and to provide documentation to FEMA and EGLE as part of Community Assistance Visits

(CAV).

Communities Must Retain Flood Records Permanently

MICHIGAN QUICK GUIDE 38

By itself, the EC cannot be used to waive the mortgage lender requirements to obtain flood insurance. See page 22 to learn about FEMA’s Letter of Map Amendment process.

n The Elevation Certificate (EC) is a FEMA form. Go to www.fema.gov and search for “Elevation Certificate.”

n The EC must be completed and sealed by a licensed professional surveyor.

n It can be used to show lowest grades adjacent to planned or existing building sites are above the Base Flood Elevation (see page 20).

n It is used to verify building and equipment elevations.

n Insurance agents can use the EC to write and rate NFIP flood insurance policies.

What is the Elevation Certificate and How is it Used?

http://www.fema.gov

MICHIGAN QUICK GUIDE 39

Completing the Elevation Certificate

In this example, the BFE is 725.0 feet.

The slab-on-grade house was elevated on fill 2 feet above the BFE; the garage is 2.5 feet below the BFE (with flood openings).

ELEVATION CERTIFICATE

(partial)

727 0 n/a n/a 722 5 727 0

722 5 726 5 722 5

X

X

X

X X X X

The Michigan Construction Code requires submission of elevation documentation two times: when the lowest floor is set and prior to further vertical construction and again prior to the final inspection.

A Michigan licensed professional surveyor must fill out and seal the surveyed elevations.

The EC includes diagrams for different building types. Several points must be surveyed.

MICHIGAN QUICK GUIDE 40

COMPACTED FILL

ELEVATION

CERTIFICATE

SURVEYED FLOOR

ELEVATION

Paperwork is Important

Lowest Floor means the lowest floor of the lowest enclosed area (including basement). An unfinished or flood-resistant enclosure (that is not a basement) is not the lowest floor if the enclosure is limited to parking, limited storage, and building access and it is built as required by the MCC. Crawlspaces are enclosures.

“As-built” Elevation Certificates must be submitted before the final inspection. Surveyors collect information helpful to verify compliance, including flood openings and elevation of equipment.

Owners should keep Elevation Certificates in a safe place. They can be used to demonstrate that buildings were compliant at the time of construction. Also, Elevation Certificates may be used to obtain NFIP flood insurance policies.

41 ......... How to Elevate Buildings in Flood Zone A/AE 42 ......... Placement and Compaction of Fill in Zone A/AE 43 ......... Basements in Flood Zones Are Unsafe 44 ......... Enclosures and Crawlspace Details (Zone A/AE) 45 ......... Utility Service, Equipment, and Tanks 46 ......... Accessory Structures 47 ......... Recreational Vehicles

FLOOD ZONE A/AE: BUILDING REQUIREMENTS

MICHIGAN QUICK GUIDE 41

ELEVATE ON FOUNDATION WALLS,

PILINGS OR PIERS

CAUTION! Enclosures (including crawlspaces) have some specific requirements.

Note: When the walking surface of the lowest floor is at the BFE + 1 ft., under-floor utilities are not allowed.

Fill used to elevate buildings must be placed properly (see page 42).

How to Elevate Buildings in Flood Zone A/AE

MICHIGAN QUICK GUIDE 42

Earthen fill used to raise the ground above the flood elevation must be placed properly so that it does not erode or slump when water rises. For safety and to meet requirements, fill should:

n Not be placed in areas with poor drainage or where the fill may divert water onto adjacent properties n Be good clean soil, free of large rocks, construction debris, and woody material (stumps, roots) n Be machine compacted to 95 percent of the maximum density (determined by a design professional) n Have graded side slopes that are not steeper than

2:1 (one foot vertical rise for every 2 feet horizontal extent); 3:1 flatter slopes are recommended n Have slopes protected against erosion (vegetation for “low” velocities, durable materials for “high” velocities – determined by a design professional) n Avoid the floodway (see pages 11 and 30)

Engineers can find more information in FEMA’s instructions for Letters of Map Revision based on Fill (FEMA Form MT-1) and NFIP Technical Bulletin 10. In Zone V, buildings on fill are not permitted.

In Coastal A Zones, the MCC limits use of fill to backfilled stem walls.

Placement and Compaction of Fill in Zone A/AE

MICHIGAN QUICK GUIDE 43

New buildings are not allowed to have basement floors below the BFE and NFIP flood insurance coverage is very limited in existing basements.

It only takes an inch of water over a door threshold or window sill and the entire basement fills up! Excavating a basement into fill doesn’t always make it safe because saturated groundwater can damage the walls.

A basement is any portion of a building that has its floor sub-grade (below ground level) on all sides.

Basements in Flood Zones Are Unsafe

MICHIGAN QUICK GUIDE 44

Enclosures and Crawlspace Details (Zone A/AE) n The MCC requires the Lowest Floor at or above BFE plus 1 foot.

n All materials below the lowest floor must be flood resistant.

n Interior grade or floor must be equal to or higher than exterior grade on at least one side.

n Flood openings must provide 1 sq. in. of net open area for every sq. ft. of area enclosed by the perimeter walls – or certified engineered openings may be used.

n The bottom of flood openings must be no more than 12 inches above the higher of the interior and exterior grades.

n Standard air ventilation units must be permanently disabled in the “open” position to allow water to flow in and out.

n See FEMA Technical Bulletin 1 Requirements for Flood Openings in Foundation Walls and Walls of Enclosures.

MICHIGAN QUICK GUIDE 45

Utility Service, Equipment, and Tanks

Fuel and propane tanks can pose serious threats to people, property and the environment during flood conditions. Search online for FEMA videos on “Fuel Tank Flood Hazards” and

“How to Anchor Home Fuel Tanks”.

Fuel and propane tanks may explode or release contents during flooding.

Even shallow water can create large buoyant forces on tanks. Tanks may be underground, elevated on platforms or columns, or at-grade and anchored to resist flood loads.

HEAT PUMP OR A/C

ON PLATFORM

FUEL OR PROPANE TANK

ANCHORED ON PLATFORM

MICHIGAN QUICK GUIDE 46

If not elevated, accessory structures in flood zones must:

n Not be habitable n Be used only for parking or storage (not pollutants or hazardous materials) n Be anchored to resist floating n Have flood openings n Be built of flood damage-resistant materials n Have elevated utilities n Not be modified for different use in the future

Accessory Structures

Sheds and detached garages in flood zones are “development” and permits are required.

By policy, FEMA limits the size of non-elevated wet floodproofed accessory structures in Zone A/AE to 600 sq. ft. Caution! Remember, everything inside will get wet when flooding occurs.

Accessory Structure, defined in the Michigan Residential Code is accessory to and incidental to a dwelling and is located on the same lot as a dwelling.

MICHIGAN QUICK GUIDE 47

Recreational Vehicles

RVs that do not meet the above conditions must be installed in compliance with the Michigan Construction Code requirements for dwellings, including permanent foundations. RVs are prohibited in floodways.

Camping near the water?

Ask the campground or RV park operator about flood warnings and plans for safe evacuations.

In flood zones, RVs must:

n Be licensed and titled as an RV (not as a permanent residence) n Be built on a single chassis n Must measure 400 sq.ft. or less (measured at largest horizontal projection) n Be road-ready, with inflated tires and be self-propelled or towable by a light-duty truck n Have no attached deck, porch, shed, or utilities n Be used for temporary recreational, camping, travel or seasonal use (no more than 180 consecutive days) n Have quick-disconnect sewage, water and electrical connectors

48..........General Requirements in Coastal High Hazard Areas (Zone V) 49 ......... How to Elevate Buildings in Flood Zone V 50 ......... The Zone V Design Certificate 51 ......... Enclosures Below Zone V and CAZ Buildings

FLOOD ZONE V: BUILDING REQUIREMENTS

MICHIGAN QUICK GUIDE 48

General Requirements in Coastal High Hazard Areas (Zone V)

Where FIRMs show a Limit of Moderate Wave Action (LiMWA), the area between the LiMWA and Zone V boundary or shorelinev is the Coastal A Zone (CAZ).

The building code treats CAZ similar to Zone V.

Revisions to Flood Insurance Rate Maps for the Great Lakes shorelines may show coastal high hazard areas (Zone V) and Coastal A Zones.

The fundamental requirements for flood resistant construction apply in Zone V and:

n Buildings must be elevated on “open” foundations…