Friday, May 17, 2019

A Week in Review: Historic High Water & A Marathon Mow

The west roadside ditch along SR 269 (right) as it overtook the road last Thursday afternoon; eventually, high water
backed up from a rising Sandusky Bay closed the road in two places between that night and last Sunday afternoon

It has been a volatile (and stressful) week along the lakefront. My post from early March regarding a consistent uptick in water levels over the last few years and particularly over the last few months -- not just on Lake Erie but throughout the Great Lakes -- provides some context . . . and in hindsight, some foreshadowing. Historically high water levels are now front page news locally, regionally, and even nationally.

I feel like I could write a book on the complexity of the situation: not just the variety of environmental factors that directly impact these vast watersheds, but on the layers of scientific research that are grappling with how to make accurate near-term and long-range forecasts. Chapters could also be written on the far-reaching impacts to all those who live and work on or near the lakeshore. These are macro-level forces. They're big, they're vast, and when they are trending into the "uncharted waters" (pun intended) that we find ourselves in now, they are scary.

A shallow excavation reveals the source
of our most pressing issue -- dike breaches
from burrowing muskrats & groundhogs
Roy spent most all of his Mother's Day weekend readying us for the worst and scrambling to react to what Mother Nature was throwing at us. The bayfront stone fortification we did back in March has already proven to be crucial in protecting the main West Marsh, but historically high water levels are now putting physical stress -- in the form of new head pressures -- on portions of the property that would have seemed out of reach just three or four years ago.

We are in the permitting process to rehab the dike that serves as our southern boundary on the west marsh. It is really our last area of significant vulnerability unless water levels just continue to march up (which would have huge impacts not just on marshes but on communities all up and down the southern lakeshore of Lake Erie). This rehab project moved to the top of the priority list about a year ago, as we continued to see water levels and projections tip ever-higher. But until we can get the green light from a regulatory standpoint, we are forced to patch problems as they arise.

High water has caused thousands of dollars in unforeseen damages on this dike in the last twelve months (a few thousand dollars just in the last week). The good news is, we do set aside a "contingency budget" each year because we know to expect the unexpected. The bad news is, we've already about surpassed out budget and it is only May. As water levels surged with three days of sustained east/northeast wind last weekend, we witnessed new leaks forming about as fast as we could repair them. We are holding on -- hopefully until the permits come through and the water starts to recede for the summer. Historically, that trend starts sometime about mid-June. It can't happen soon enough.

The main culprit of our leaks right now (other than the water itself)? Our good friend the muskrat. Because we need to maintain higher water levels within the marsh (to reduce head pressure from rising water outside the marsh), muskrats are given access to new soil within which to dig. And these furry, little excavators are pretty darn adept at digging -- especially when the soils are soft and saturated.

Rats: they can look so "cute" and harmless when basking in the afternoon sun of a dry dike

Sheri Amsel does a nice job depicting what a conventional muskrat "hutch" would look like, say in a pile of decaying cattails. As I wrote on very early on, these water-loving rodents play a vital role in the health of coastal wetlands. However, as they make Swiss cheese of our aging south dike, they risk compromising the very habitat that they depend on -- because if we loose our dike (via a major breach), the water levels within the marsh will surge, the rooted vegetation will be lost, and the muskrat's habitat will go with it. As with so many things in the natural world (especially when human intervention has become complexly intertwined), the balance can be tenuous.

ASIDE: One other side effect of the high water is that we are reluctant to bring a heavy tractor onto our earthen berms to mow. This meant that I got to burn off some of my high-water stress walking behind the 30" deck of our brush mower these last couple days. About eight hours and ~26 miles of walking later, the entire East Marsh has been mowed. I'm a bit sore today, but it feels really good to have this project behind us . . . at least for another few weeks.

Before (left) and after (right) mowing our eastern-most dike. The "before" photo features poison hemlock that was about sternum high.
Now at least we can see if muskrats create any new issues.