On Earth Day last Monday, the state legislature’s Joint Committee on Environment voted to send on to the Senate a bill to assess the long-term risks from sea level rise.
Climate change is expected to result in as much as 2 meters of sea level rise over the next century. At the same time, with greater storm severity, longer and heavier periods of northeast winds blowing water towards the shore could increase storm surge heights.
The damage that Hurricane Sandy did to New York warned all coastal cities of the impending danger: If the monthly peak high tide happens to coincide with a storm surge on top of a higher base-line sea level, then there is a great risk of flooding in our low-lying areas. Much of our prime real estate and valuable infrastructure sits in those areas.
The danger may be particularly acute in the Charles and Mystic watersheds where we have built heavily on former swamp land. Many people don’t realize that the Charles and Mystic River basins are maintained at an artificially low level by sea walls that keep the high tide out. If those walls were over-topped by high seas, and, at the same time, the rivers were swollen with rain, huge damage could be done.
Not to be too alarmist: The sea walls at the mouths of the Charles and Mystic are equipped with huge pumps that are sized to keep up with some amount of over-topping back flow. The immediate risk is low, but some good modeling needs to be done to reassess the risk as climate changes.
That is precisely the goal of my legislation which the Environment Committee took up last week. The bill would charge the state’s Secretary of Energy and Environmental Affairs with creating an advisory group to develop some alternative scenarios for coastal flooding over the next century.
We should be fully prepared for the sea level rise and increased storm surge that most likely will, in fact, happen. And we should have some sense of how we would respond if the more pessimistic scenarios come to pass.
Our most critical assets — like our sewage system, our power grid and our public transportation system — should be fully protected in any reasonably probable scenario. The damage that occurs when critical systems are incapacitated by flooding goes well beyond the damage to the systems themselves. We could face months or years of diminished regional productivity.
Under the legislation, once the advisory group defines scenarios, state agencies and utilities with at-risk assets will report back to the Secretary on what it would cost them to protect their assets. The Secretary will then assemble a final report which should help state government make the necessary long-term plans. Big infrastructure investments often have lead times that run in the decades, so now is the time to get started.
A number of agencies and groups are already done some great work on the issue — the City of Boston, the City of Cambridge, the Charles River Watershed Association, and the Boston Harbor Association, to name a few. My hope is that with the authority that my bill would grant, the Secretary will be able to draw people together into a collaborative process that leads to the necessary safety investments in a timely way.
The next step is for the Senate to consider the legislation. So far, the response from my colleagues has been very positive.