Saturday, August 7, 2010

Erosion control at the Round Cove Rd parking area

Please pardon our dust!

Temporarily, there may be a little inconvenience.  But the work is necessary to keep the pond clean!

Staff from Nickerson State Park, plus a volunteer, have begun restoration work at the Round Cove Rd parking area.

Temporary "silt socks" act like dams, slowing runoff and catching sediment.

Two jobs are underway:
  • Stop erosion starting in the parking area, with runoff heading towards the beach.
  • Fill in the big puddle, which swallowed two cars last week!
Erosion is a threat to water quality

Runoff washes nutrients like phosphorus and nitrogen into the pond.  At many ponds ringed with cottages, nutrients get into the pond from leaking septic systems.  But at Hawksnest where there's only one cottage, erosion from steep slopes all around the pond could become the biggest source.

If enough nutrients accumulate, they can stimulate the growth of toxic and stinking algae.  The sudden "blooms" of algae can completely unbalance the pond, resulting in fish kills.  Many ponds in Harwich have already been damaged by too many nutrients.  Once the nutrients get into the pond, most of them stay forever.  The pond becomes permanently damaged.

Phosphorus is insoluble, so it gets into the pond by "hitchhiking" on tiny soil particles.  Runoff also washes pet waste, and even human waste from the parking area, into the pond.  So without erosion control, the beach area could become contaminated.

The gully above the beach is too big a problem for this year--perhaps next.  But please observe the signs here, and keep your dog from running on or digging in the bank.

How silt socks work

The socks are filled with pure sand.  They act as a dam, slowing the runoff and allowing it to sink into the porous soil.  If the ground gets to wet for the runoff to sink in, then the socks slow the water, and catch the sediment.

One value of silt socks is that you don't have to disturb the ground or the roots where they are laid.

In appreciation of the "world-class" status of Hawksnest swimming, the socks were donated thanks to a company in Wisconsin.

No parking near the giant puddle

Once this spot was a beautiful open glen, with ferns and lady slipper orchids.  But as the upper parking area eroded, it became a basin, sending more water towards the puddle.  The puddle became an unsightly hazard for vehicles, plus a "cesspool" for waste washing from the parking area.

Giant puddle, smoothed.  Still very soft!  Next: leaf litter on top.

Now the smoothed-over puddle looks solid, but it is very soft under the surface.  Vehicles will sink in, ruining the restoration.  That's why parking has to be banned here.  But you may park in the hollow, on the side of the road AWAY from the pond.  There's room for several vehicles there.

Once restored, the hollow will be a lovely spot to rest, after a swim.  If you see parking violations here, please report to Harwich Police (508-430-7541).

One trail to beach will be closed

Hawksnest is a fragile resource, because of the steep, easily-erodible banks around most of the pond. From time to time, it may be necessary to close some trails if they become eroded, to allow time for vegetation to recover. We want to maintain access--trail closure is simply a good management tool. If a trail has to be closed, usually it will be only temporary.

As you face the pond from parking, on your LEFT there's a steep trail to the pond (see photo).  This needs to be closed for several reasons:
  • Safety--the trail is steep, with roots and exposed wires (from a former cabin) ready to trip the unwary.  If you fall, exposed cement blocks add to the danger.
  • Erosion.  This is a long, steep trail.  If erosion ever gets a head start, it will be very costly to repair.  Once the roots become undermined and broken (as a few are), it's the beginning of runaway erosion.
The horse trail that heads west from the upper parking area may be redirected.  That's because it is starting to erode, and contributes stormwater to the big puddle.  This trail won't be closed--just a slight change in route.

You can help avoid trail closures--he best way is to help with the trails.  If your favorite trail starts to show signs of erosion, dig a little ditch to deflect the runoff to the side.  Or, build a little log step that deflects the runoff.

The trail to the southeast beach (from the middle of Round Cove Rd) could be an area of future erosion.  It's becoming more heavily used, and heads downhill.  Please help prevent closure and maintain this trail!

The State's plans for future work

In June, the DCR applied to the Harwich Conservation Commission for a permit to undertake permanent erosion improvements in the Round Cove Rd area.  When the Commission voiced concerns about access to the area, and that people in Harwhich didn't have time to voice their opinions, the State withdrew the plan.  (The State's plan for the Walker Rd parking area were approved.)

The DCR will resubmit the Round Cove Rd plan for approval, after there's been ample time for public discussion, probably sometime this fall.

However, even if those plans are approved, the work may never take place.  That's because this is an election year, and also the State has NO funds for this kind of work.  Because the erosion was becoming steadily worse, Friends of Hawksnest persuaded the State to permit the temporary erosion control measures you see in progress.  All the work you see has been approved by State officials.

The permanent plans did not include beach access at Round Cove Rd.  Whether that was an oversight, or an active plan to limit access, we don't know. 

Nevertheless, Friends of Hawksnest supports beach access from Round Cove Rd.  We support any legal use of the park.

Some comments we've heard about the work

We've heard numerous words of encouragement.

What do you think?  I hope it's not inconvenient.
Anything is better than nothing!

This is really ugly! (referring to the black silt socks)
I know, we think it's ugly too.  But if vegetation gets re-established, it's going to look a lot better.  The restored puddle already looks a lot better.  If it's ugly, do you blame the people repairing the damage, or the folks who made the repairs necessary?

It's been eroding on Cape Cod since the Indians.
Well, yes, there's a lot of erosion along the salt water beaches.  The wind, waves, and tides are a powerful force.  People are used to seeing eroded banks at the ocean beach.  But eroding banks around sheltered ponds used to be very rare.  That's why some ponds are so clean.  Unlike the ocean, the ponds can't absorb the pollution from erosion.

Erosion is natural--water runs downhill.
True, gravity is natural.  If a tree falls on you, that's natural.  But it doesn't mean it's desirable.  Vegetated shores keep the pond clean.  "If the shore is green, the pond is clean."  Before settlement, the vegetation everywhere was intact.  Losing the shore vegetation is bad management.  Erosion and the loss of water quality is a "natural consequence" of a bad management practice.

Every pond I've seen in Cape Cod has erosion.  It's natural.
True, most ponds have eroding banks, and most ponds in Cape Cod are damaged.  Some are already  badly polluted with algae.  Hawksnest is one the the last pristine ponds.  Let's keep it undamaged, so your grandchildren can swim in pure water, just as you do now.

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