How to Complete a Flood Risk Assessment

How to Complete a Flood Risk Assessment

The purpose of a flood risk assessment (FRA) is to evaluate the likelihood of flooding and its potential impact on people, property, and the environment. It is often required for construction projects, especially in flood-prone areas, or to secure flood insurance. 

If you aren’t aware of any bodies of water in proximity to your property, you may be wondering: Why do I need a flood risk assessment? Here’s the thing: Some flood risk factors are obvious, like nearby river or coastal waters, but others only reveal themselves after periods of continuous rain, like groundwater (unless you know what to look for).

In this article, we’ll explore whether it’s best to do your own assessment or hire a professional, discuss the different types of professionals you can call on if you outsource the task, and detail how flood risk is assessed. 

DIY Flood Risk Assessment vs Hiring Professionals

Completing a flood risk assessment is an essential step in understanding your property’s vulnerability to flooding and knowing which measures are appropriate for mitigating risks. If the reason you need an FRA is to comply with government regulations – particularly for construction in flood-prone areas – or to satisfy insurance and mortgage requirements, you need to hire flood risk assessment consultants. 

But if you’re more so wanting to get a sense of a property’s likelihood of flooding, you can use many of the same tools the pros use to get a decent personal understanding. Let’s take a closer look.

DIY vs. Hiring Professionals

Who to Hire: Flood Risk Assessment Consultants

There are several types of professionals and organizations with expertise in flood risk analysis, engineering, or environmental science. Who you choose to engage will depend on the impetus for the FRA. Here’s a breakdown of who you can hire to complete a flood risk assessment, their typical roles in the process, and how you can find the best person for the job.

• Insurance Assessors or Specialists
  Some insurance companies provide or recommend flood risk assessors to help homebuyers or homeowners assess flood insurance needs. Check with your insurance provider or agent for information.

• Flood Risk Surveyors
  These professionals focus specifically on assessing flood risks for residential and commercial properties, often for insurance or planning purposes. Flood risk surveyors are a great choice for homeowners, developers, or businesses needing a clear understanding of site-specific flood risks. To find them, search for certified flood risk assessors through professional organizations like the National Flood Insurance Program (NFIP).

• Licensed Civil Engineers
  Civil engineers who specialize in hydrology and water resource management can evaluate flood risks, drainage systems, and structural vulnerabilities. They’re best for assessments related to new construction, renovations, or properties with complex drainage or water flow issues. Find them by searching for engineering firms in your area or consult local engineering societies.

• Environmental Consultants
  Environmental consultants analyze broader environmental risks, including flooding, erosion, and groundwater issues. They can provide detailed reports for regulatory compliance and are the ideal hire for properties near environmentally sensitive areas, such as wetlands, rivers, or coastal zones. Look for consulting firms specializing in environmental assessments.

• Hydrologists
  Hydrologists study water movement and can model flood behavior for specific locations. They’re usually involved in large-scale flood risk assessments and are best for areas with complex water systems or properties with significant flood exposure. Universities, research institutions, or specialized firms often employ hydrologists.

• Architects or Builders with Flood Expertise
  For new construction or renovations, architects or builders with flood mitigation experience can assess risks and design flood-resilient features. This is the route typically chosen by those planning to build or remodel in flood-prone areas. Look for professionals with certifications in flood resilience or sustainable design.

• Local Government or Planning Departments
  In some cases, local authorities offer flood risk assessment services or maintain partnerships with private firms. This is a smart option to consider if compliance with local zoning or building codes is of top concern. Contact your city or county planning office to see if this service is offered.

• Specialized Flood Risk Assessment Firms
  For high-risk properties or areas where comprehensive analysis is required, considering a firm that focuses exclusively on flood risk analysis, using advanced modeling tools and GIS mapping to provide detailed assessments, may be the best choice. Search online for flood risk assessment firms in your region to find them.

How to Assess Flood Risk

When you hire a professional to complete a flood risk assessment, the process typically begins with a consultation. The consultant will determine the purpose of the assessment, such as construction permits, insurance requirements, or property purchase, and conduct a preliminary site visit to understand the physical characteristics of the property.

Next is data collection, when professionals gather relevant data that will be used to evaluate vulnerabilities, including: 

• Flood zone maps: Government or regulatory maps showing flood risks.
• Topographical data: Detailed information about the property’s elevation and slope.
• Historical records: Data used to investigate previously flooded areas 
• Weather patterns: Climate data to predict potential changes in flood risks.

The data collected on the property and reason for the FRA will inform the type and method of risk analysis needed, and may include:

• Hydraulic modeling: Using software to simulate water flow and flood scenarios under various conditions, such as heavy rain or rising river levels.
• Flood source identification: Evaluating risks from rivers, coastal surges, groundwater, and surface water runoff.
• Probability assessment: Determining the likelihood of flooding based on historical and environmental data.

Next is the impact assessment, which examines the potential consequences of flooding. This is the driving force behind seeking an FRA; the meat and potatoes of the assessment. The impact assessment will detail prospective:

• Damage to property: Structures, utilities, and landscaping.
• Human safety: Risks to occupants or users of the property.
• Environmental effects: Pollution or damage to ecosystems caused by floodwaters.

Flood Risk Mitigation Recommendations

With the impact assessment in hand, your professional team will determine what mitigation measures to recommend. These are tailored to fit specific circumstances and levels of risk. These run the gamut and often combine several strategies to create a multi-layered flood mitigation plan that balances structural improvements, natural defenses, and emergency preparedness. 

• Structural & Building Modifications
  Examples include elevating buildings above the base flood elevation (BFE); installing permanent or removable barriers; adding vents to crawl spaces or basements; sealing walls, floors, and foundations with waterproof coatings or membranes; and elevating utilities above expected flood levels.

• Drainage & Landscaping Solutions
  Some drainage and landscaping solutions are purely functional, like grading the land to adjust the slope; installing french drains and permeable paving; and creating shallow channels to redirect runoff. Others have added benefits, like designing rain gardens; upgrading retention ponds; or adding green roofs. Planting trees and shrubs and strategically placing rocks can help stabilize soil and reduce runoff velocity and prevent erosion near water bodies.
  
• Interior Adaptations
  It’s wise to use flood-resistant materials in flood-prone areas, like ceramic tile or concrete instead of carpets or wood, and using closed-cell foam insulation. Keeping valuables and electrical equipment above expected flood levels and using shelving instead of floor-level units are easy solutions, too. Adding valves or plugs to prevent sewage from backing up into the property during floods is key.

• Technological Solutions
  Flood sensors and alarms can serve as critical early detection systems to alert you when water levels rise. Consider integrating smart home features with automated shutoffs for utilities like electricity and gas.

• Emergency Preparedness
  Arming yourself before a flood can give you tremendous peace of mind and reduce water damage after the fact. Sandbags can be a quick barrier to block water flow; water-filled or air-filled barriers can be effective too. Sump pumps remove water from basements and crawl spaces quickly. Installing a generator can ensure critical systems continue functioning during inevitable power outages.

Whether you have concerns about the prospect of flooding on your property, don’t wait until the threat of flood is imminent – connect with us! We are here to support you as you determine next steps and seek the appropriate coverage for your specific needs.