A grandma cracks crab on her porch at Iverson Beach as she watches her grandkids defend a sandcastle against the incoming tide. Fast-forward 40 to 60 years when the grandchildren become grandparents. Now they must defend the beach house as king tides breach the bulkhead and swamp the yard, threatening the well, septic system and foundation.
Thanks to the Washington Coastal Resilience Project and a Sea Level Rise Strategy Study, Island County has strategic planning tools to help shoreline property owners manage rising sea levels.
Just as county officials started rolling out an educational campaign to share these new tools, COVID-19 hit. The Camano Island presentation was cancelled. Instead, a recorded presentation is available online with the study.
“We were hoping to go out to our shoreline communities and do more outreach,” Meredith Penny said. She’s the county’s long-range planner who was involved in the sea rise study along with Jonathan Lange, county planning manager.
Penny said information could be used in handouts for homeowners and developers getting permits, and making land-use plans while monitoring keeps information current.
In 2018, Projected Sea Level Rise for Washington State predicted that sea levels would rise 1 to 3 feet by 2100 — 80 years from now.
After recent measurements of melting ice in Greenland and Antarctica, NASA predicts sea level will rise 3 to 4 feet by 2100, enough to inundate some coastal cities. NASA warned this is a conservative estimate.
The National Oceanic and Atmospheric Administration sea rise map shows that 1 foot of sea rise would put Iverson Beach under water; 2 feet would push Livingston Bay through yards and fields, north to Highway 532. The NOAA map shows that sea rise would take a sliver of beach all around Camano Island. In some cases, that’s all the beach there is.
Island County is especially vulnerable to sea level rise with 196 miles of shoreline, much of which is private property.
Since 1990, Island County has made disaster declarations in response to eight extreme flooding events from severe winter storms and tidal surge.
Damages to private property included overtopping of bulkheads, inundation, ground floor flooding, prolonged site drainage, restricted beach access and failure of septic systems and wells.
Sea Rise Study
The Washington Coastal Resilience Project is an effort to rapidly increase the state’s ability to prepare for coastal hazards related to sea level rise.
As part of the project, Island County recently took part in the Island County Sea Level Rise Strategy Study. The study was a collaboration of Washington Sea Grant, University of Washington Climate Impacts Group, University of Oregon, University of Washington and US Geological Survey.
It looked at different types of Island County shoreline communities, what types of problems they are likely to have and a range of solutions over time. It includes planning tools for shoreline owners to use — individually and collectively — to protect homes and communities against rising tides.
The report looks at the geology of shoreline communities, including bluffs, low beaches, surface water, groundwater, aquifers and recharge areas. Shoreline residences fall into three main categories, each with specific risks and solutions.
• Historic Beach Communities: Homes are crowded on small lots within 30 feet of the ordinary high water mark, usually along beaches and spits. They were built before the 1972 Shoreline Management Act. Examples include Utsalady Bay and Madrona Beach.
• Canal Communities: Developments are built along an engineered canal. Camano has none, but Whidbey has three.
• Coastal Bluff Communities: Homes are built both atop and at the base of unstable slopes, like Maple Grove and Tyee Beach.
Impacts of rising seas
Seas are rising because of melting ice sheets and glaciers. As seas rise, intertidal areas are in danger of disappearing. These wetlands, estuaries, mudflats and marshes are home to wildlife, fish and invertebrates. Millions of migratory waterfowl overwinter here.
Wetland zones store floodwaters and limit storm surge, protecting communities. Many wetlands will be submerged by sea level rise. Extreme storms will hit shorelines more frequently. New areas will be flooded and those that already flood will flood more often.
Rising seas could affect groundwater levels and cause saltwater intrusion in wells, which Camano residents rely on. It could harm vegetation and cause septic system to leach. Erosion can cause “cliff retreat” or landslides, threatening homes perched above or nestled below on the narrowing beach. Beaches could shrink, with waves carrying sand away to deposit elsewhere. This is a natural process that could be exaggerated.
The study states that the current Island County Comprehensive Plan doesn't protect against sea level rise. It's based on flood zones established by the Federal Emergency Management Agency. These flood maps are based on historical 100-year flooding and do not account for tidal surge, extreme high tides or projected sea level rise. Maps were last updated in 2017.
County development regulations call for the lowest floor of structures in high hazard areas to be at least one foot above base flood elevation, which is based on FEMA flood maps. The same is true for rules governing septic systems and ordinary high water marks.
“FEMA looks at historical trends of floods over time, mapping 100-year floods. But when you’re looking at sea level rise, you’re looking at not what previously occurred, but you’re projecting what it might look like going forward,” Penny said. “What’s going to be the new normal? Where will the new water level be 100% of the time?”
Counties are not mandated to address sea level rise, but encouraged, she said.
“Counties do have to consider changing conditions and best available science,” Penny said.
The study recommends that Island County join the FEMA Community Rating System, which requires stronger development regulations to address potential impacts from projected sea level rise. It could reduce shoreline property owner flood insurance rates, as well.
Putting knowledge to work
The county’s approach to addressing sea level rise is to educate builders and homeowners.
“Right now, we want to provide up-to-date and accurate information to the community and give guidance, so people can start having conversations and plan ahead,” Penny said.
Information is the important first step. It will take a lot of private initiative and community planning to achieve coastal resilience, she said.
The study offers a guide with worksheets to help communities. Water and homeowner associations can plan around their specific infrastructure and assets. The guide takes people through many steps of deciding what to do, how to find resources and how to finance.
“It’s a process of creating their own resiliency plan,” Penny said.
When there’s a plan, people can choose the best option for their situation. They can see how things progress over time and adjust. They’ll know when to act and allow time to put finances in order.
Individuals would decide how much risk they will tolerate and what investments to make for their property. A homeowner who plans to eventually move will have different goals than someone who is building a home to their children and grandchildren, she said.
Putting a cost on solutions to sea level rise is difficult. Each community is unique, and there’s a range of strategies that can be activated based on observed impacts.
Property owners can work collectively, using county guidance. Community members can assess their vulnerabilities and establish thresholds for taking action. For example they might say, “Once we see x inches of sea level rise, we will take this action,” Penny said.
Measures include building community drain fields, bulkheads, breakwaters, floodwalls or dikes. People can build elevated structures and include floodable spaces. Some homes might be moved to higher ground.
Problems on parcels can lead to community hazards. Contaminants released from septic systems, creosote-soaked piles in tidal areas and household hazardous waste can cause long-term damage to the surrounding ecosystem.
Some solutions work better on a community-wide scale, like installing a community drain field, acquiring property for shoreline protection measures or dike repair, Penny said.
Watching the changes
“The county is working on a monitor program to study how sea level rise will impact us over time. County guidance might change depending on how fast sea rise is compared to predictions,” Penny said. “How much water is going to rise? How much is the land sinking or rising due to tectonic geological processes? Luckily that’s baked into the Washington Coastal Resilience Project’s projections.”
The county is partnering with the Watershed Co. and Herrera Environmental Consultants to study sea level rise and other things that go with it. The county continues to evaluate its strategy as monitoring data updates the current picture.
“There are a few tide gauges already out there monitoring. We want to look at other things as well, like bluff erosion rates and whether coastal bluffs start eroding more on one side of the island than the other,” Penny said.
See the NOAA rising sea level map: coast.noaa.gov/digitalcoast/tools/slr.html
Read the Island County Sea Level Rise Strategy Study: tinyurl.com/CountySeaStudy
Listen and watch a 30-minute slide presentation: tinyurl.com/CountySeaStudySlide