All (green) hands needed on deck - getting ready for sea level rise
Three years ago the Province released a report estimating it would cost $9.5 billion to prepare the Lower Mainland for rising sea levels by 2100. The report focused on “hard” solutions: dikes, sea gates, flood walls. But before we, say, wrap the region in expensive (and ugly and habitat destroying), concrete “super-dikes”, like post-tsunami Japan, we could follow the lead of other jurisdictions that are thinking more creatively about coastal resilience and rising sea levels.
A new study prepared by researchers from the US National Oceanic and Atmospheric Administration (NOAA) tells us that:
There is substantial evidence that natural infrastructure (i.e., healthy ecosystems) and combinations of natural and built infrastructure (“hybrid” approaches) enhance coastal resilience by providing important storm and coastal flooding protection, while also providing other benefits. There is growing interest in the U.S., as well as around the world, to use natural infrastructure to help coastal communities become more resilient to extreme events and reduce the risk of coastal flooding.
… Built infrastructure…is limited in that it only provides coastal protection value and only during storm events…Indeed, many of the co-benefits associated with natural infrastructure are precisely what make coastal areas so valuable and what draws people to live and work in these oft-vulnerable regions.
So beaches, reefs, salt marshes, and different types of marine vegetation can all play a role in protecting our communities. If that's the case, then why aren’t we looking more closely at these types of solutions? As we explore below, our legal framework is putting up some hard barriers of its own.
Sea level rise – slow but sure
Provincial guidelines for BC suggest that by 2100 sea levels in most coastal areas in BC will be about 1 m higher than at present, and that we should prepare for 0.5 m by 2050. What’s more, sea level rise won’t suddenly increase by 0.5 m in 2050, and it won’t stop at 1 m in 2100. Sea level is going to be gradually increasing every year, from now on, thanks to a changing climate. There are two main reasons: a warming ocean is expanding, and melting glaciers and polar ice sheets will eventually add significant amounts of water.
Until very recently, nobody in BC (or elsewhere in the world) was planning for sea level rise in coastal or island communities, and in many places we have substantial levels of development at or near sea level. While we still have some time to react, we need to use this time wisely. How long will it take to prepare, or re-locate, a house, a road, a skyscraper, or a sewage treatment plant? How should we be designing new developments in vulnerable areas so we don’t create further, expensive problems for ourselves? What are we doing to protect precious remaining foreshore habitat, which will be submerged if there’s no space to migrate landward? What are the impacts on marine species? Some advisors have called sea level rise a “slow-moving emergency”, and it’s not hard to see why.
Sea level rise and BC flood regulations – not a perfect fit
From a legal perspective, who is responsible for preparing our communities? Sea level rise is generally being managed as a flood hazard, and since 2003 local governments are largely responsible for managing flood hazards in coastal towns and cities, and designating flood plain areas, taking into consideration provincial guidance documents (see s. 910, Local Government Act). While it makes sense to characterize sea level rise as a flood hazard, because it’s about things getting wet, this existing regulatory framework has some gaps and shortcomings that, we argue, make it less than certain that we are going to be adequately prepared for rising sea levels.
The idea behind flood plain mapping and designation, for example, is to discourage development in flood-prone areas or to ensure that it is flood protected. The tools are setbacks and requirements for elevating the ground floor of buildings (flood construction levels, or FCLs). So far, so good, but for many coastal areas facing sea level rise, it’s too late--the development is already there. Where redevelopment or new development is occurring, the response has been mixed. Some local governments are mulling over what to do, reluctant to designate new floodplains because of a perceived impact on property values (research on this point is inconclusive).
Adding to the indecisiveness is uncertainty around the application of the Compensation and Disaster Financial Assistance Regulation. This regulation helps to compensate for the lack of overland flood insurance in BC, and provides funding to homeowners and small businesses to clean up and repair buildings after a flood occurs. However, in order to qualify, buildings and structures in a designated must be "properly flood protected", as interpreted by the Province. According to a 2006 policy document, the Province takes this to mean in accordance with provincial guidelines, the same ones that local governments have to "consider." This seems to limit local government flexibility to regulate developent in designated flood plains. Local governments can sidestep this tricky relationship between s.910 and the compensation regulation by using other tools to require flood protection, such as development permit areas, but there still won't be any guarantee that compensation from the Province will be forthcoming in the event of damage from flooding. Several Lower Mainland municipalities (Vancouver, City of North Vancouver, District of West Vancouver, Squamish) have moved forward with significantly increased FCLs in areas exposed to sea level rise, using various approaches and sometimes characterized as an “interim” measure. However, while this approach has to be regarded as proactive and prudent, it is not without practical challenges. New development will be higher (e.g. raised on fill), but existing development, e.g. both adjacent properties and infrastructure, such as roads and sidewalks, will be lower, and in some cases much lower.
As well, the type of flooding that our flood management regime contemplates is a rare, temporary occurrence, where waters rise rapidly for a short period of time and then recede. Disaster financial assistance doesn’t provide funding to prepare for flooding before it happens. Sea level is going to rise slowly, but it won’t recede. Commercial property owners may have insurance, and it is possible that increased insurance rates could trigger adaptation of commercial buildings and properties, where feasible, but this still won’t address larger issues around infrastructure and coordinated neighbourhood or larger-scale responses. In the United States, for example, the National Flood Insurance Program has already instituted progressive increases in insurance premiums, but other than cost recovery it remains to be seen whether this will result in affected communities being more prepared.
Designing with nature for coastal resilience
It is evident that from the perspective of sea level rise there are some gaps in regulating how our built environment will evolve to adequately protect our communities. Missing altogether is explicit reference to integrating living, green infrastructure into our responses, though the multiple benefits and long term resilience associated with these approaches have even been recognized by organizations like the US Army Corps of Engineers, not previously known for championing environmental causes. In January 2015 President Obama issued an Executive Order, which proposed that "natural systems, ecosystems processes, and nature based approaches" should be considered as flood management strategies in all federally funded projects.
Studies in BC and elsewhere have demonstrated that beaches, mudflats, offshore reefs, eelgrass and other natural and eco-engineered features can provide an effective buffer from sea level rise and associated storm surge, in addition to habitat and aesthetic values. Not only can coastal habitat provide a protective buffer, it can also support an approach that accommodates sea level rise in coastal communities, where roads become waterways and wetlands are created or expanded. To work, this needs to be accompanied by a move towards buildings with designs that allow them to be resilient to to a certain amount of flooding, or, perhaps, amphibious.
In BC we have significant experience and capacity using green infrastructure solutions at the local government level to manage stormwater, improve water quality and protect fish habitat. Riparian buffers, tree canopies, healthy topsoil and reducing impervious surfaces all help reduce the demand on our grey infrastructure of pipes and drains during extreme precipitation events. Metro Vancouver’s Integrated Liquid Waste and Resource Management Plan is an example of a framework for implementation at a regional scale. What can we learn from this experience, sometimes called “designing with nature”, to make our communities more resilient to sea level rise?
We know from green infrastructure and rainwater management that for greatest effectiveness we need to combine work at all scales, from the watershed down to the site. To manage sea level rise at the site and neighbourhood scale we need a more nuanced approach to flood construction levels. At a larger scale in the coastal context we need to look at coastal reaches, and at the interface between coastal waters and upland drainage. For local governments, this is challenging. In some areas, much of the coastline is under the jurisdiction of federal port authorities. Outside of these areas, the foreshore, the land from the high water mark to the sea, is Provincial Crown land, and local government authority is limited. In more densely populated areas, the coastline is also highly affected by development, meaning that restoration will need to be undertaken. A 2009 assessment showed that approximately 65% of the shoreline of the Burrard Inlet (190 km) has been hardened with riprap or a retaining wall.
Local governments alone do not have adequate authority, capacity or funding to realize the benefits of coastal resilience through coastal management. Greater regional cooperation will clearly be necessary. Yet the response to the recent spill of bunker fuel in the Burrard Inlet demonstrated the fragmentation of responsibility for different aspects of coastal management and protection among various levels of government and government agencies, and the lack of any clear coordination or mandate. Still, there is hope. We may not be able to expect federal action, but the MaPP process recently completed on the North and Central Coast suggests that provincial and First Nations governments working together may be able to provide leadership, and create a regional scale plan that could be incorporated into local government planning and regulation.
By Deborah Carlson, Staff Counsel