Hillslope Fix Underway on Stony Clove Creek

Posted on: April 15th, 2016 by Leslie_Zucker

A new stream project began in late March on the Stony Clove Creek near Wright Road in the Town of Hunter. The project is nec­es­sary to sta­bi­lize a large fail­ing hill­s­lope and ensure the suc­cess of last year’s chan­nel restora­tion at the same loca­tion. Both projects should improve water qual­i­ty by reduc­ing the like­li­hood of sed­i­ment from the hill­s­lope enter­ing the Stony Clove and reach­ing the Eso­pus Creek.

Flood­ing dur­ing Trop­i­cal Storm Irene desta­bi­lized the Stony Clove Creek upstream and down­stream of the Wright Road bridge. A stream restora­tion project was com­plet­ed in 2015 to sta­bi­lize the chan­nel and pre­vent future erosion.

The project treat­ed 2,675 feet of the Stony Clove Creek. To halt ero­sion at the toe of the slope, the stream restora­tion project focused on adjust­ing the chan­nel width and depth, along with cre­ation of flood­plain bench­es and grade con­trol structures.

The project area includ­ed a large hill­s­lope that showed signs of geot­ech­ni­cal fail­ure, although not as advanced as down­stream fail­ures treat­ed in 2013–14 near Chich­ester. After­ward, long-term mon­i­tor­ing of the hill­s­lope began to track any future advance­ment of the failure.

New prob­lems emerged as clay in the hill­s­lope con­tin­ued to cause slid­ing over the top or through the rock toe that now exists at the hill­s­lope base. Engi­neers from the NRCS and engi­neer­ing firm Milone & MacB­room, Inc. (MMI) eval­u­at­ed options for mov­ing for­ward and MMI pre­pared a design for repair­ing the hill­s­lope. The design includes cap­tur­ing and redi­rect­ing water that sat­u­rates the fail­ure, as well as debris clear­ing and re-grad­ing steep areas of the bank.

Trees are felled for clearing on a failing hillslope bordering the Stony Clove Creek near Lanesville, NY. The slope will be graded and drainage installed to prevent erosion and improve water quality in the upper Esopus Creek watershed.

Trees are felled for clear­ing on a fail­ing hill­s­lope bor­der­ing the Stony Clove Creek near Lanesville, NY. The slope will be grad­ed and drainage installed to pre­vent ero­sion and improve water qual­i­ty in the upper Eso­pus Creek watershed.

Con­struc­tion at the site began in late March and is expect­ed to run through August 2016. Kingston Equip­ment Rental, Inc. (Bak­er Broth­ers Exca­vat­ing) out of West Hur­ley was the con­trac­tor for last year’s stream work and will con­tin­ue with the hill­s­lope sta­bi­liza­tion project. The Ulster Coun­ty SWCD is pro­vid­ing over­all project management.

The Nat­ur­al Resource Con­ser­va­tion Ser­vice (NRCS) has agreed to fund 75% of the project costs asso­ci­at­ed with sta­bi­liz­ing the hill­s­lope. The remain­ing 25% local will be paid by the New York City Depart­ment of Envi­ron­men­tal Pro­tec­tion (DEP) and admin­is­tered by the Ulster Coun­ty Soil & Water Con­ser­va­tion Dis­trict (SWCD).  The Town of Hunter is the project sponsor.