20090104 Ver 3_Complaint Investigation_20131205

NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Resources
Water Quality Programs
Pat McCrory Thomas A. Reeder John E. Skvarla, III
Governor Director Secretary
December 5, 2013
MEMORANDUM
To: Tom Reeder, Director, Division of Water Resources (DWR)
Through: Amy Chapman, Supervisor, DWR Transportation Permitting Unit
From: Rob Ridings, DWR Transportation Permitting Unit
Subject: Complaint investigation of potential sediment loss on the Rolesville bypass project in Wake County
This report is to follow up on a complaint from State Senator Barefoot's office received by Tom Reeder and referred to
Rob Ridings on November 26, 2013. The complaint involved a significant amount of sediment buildup in Upchurch Lake
in Rolesville. Sediment had been reported filling in the headwaters of Upchurch Lake coming down from Harris Creek.
The citizen complainant believed the sediment had migrated downstream from the construction of NCDOT's Rolesville
Bypass project (TIP# R- 281413). This project has been issued a 401 Water Quality Certification and Neuse Buffer
Authorization in 2010 from this unit (WQC# 3790). The crossing of Harris Creek is at the Permit Site # 8. This site
involved putting 355 linear feet of Harris Creek into a box culvert, along with some bank stabilization riprap on both the
inlet and outlet.
This project has been reviewed numerous times by Rob Ridings during regularly held Inter - agency reviews along with the
NC Department of Transportation (NCDOT), and the US Army Corps of Engineers, since the beginning of the project in
2010. To date there had been no compliance issues on this project.
On Monday, December 2, 2013, Rob Ridings investigated the project area in question, along with Donald Pearson, an
inspector from NCDOT's Roadside Environmental Unit. Mr. Ridings was able to confirm that there was indeed sediment
built up in the headwaters of Upchurch Lake, as seen in Picture 1.
Transportation and Permitting Unit
1650 Mall Service Center, Raleigh, North Carolina 27699 -1650
Location 512 N. Salisbury St Raleigh, North Carolina 27604
Phone 919 - 807 -63001 FAX 919 - 733 -1290
Internet: www.ncwaterguality.org
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Picture 1: Sediment built up in Upchurch Lake where Harris Creek enters.
Further investigation was made to determine if the sediment had come from NCDOT's project. In regards to sediment
and erosion control measures at the impact site, all devices appeared to be maintained well and in working order. These
included sediment basins with skimmers (Picture 2), check dams, silt fences, temporary seeding/mulch, and special
sediment control fences (Picture 3), all constructed to NCDOT's standard specifications. These devices appeared to all
be in good condition and working order.
Picture 2

Picture 3
Mr. Ridings then investigated along Harris Creek to see the condition of the creek as well as other possible sources of
sedimentation, since there was no obvious source coming from NCDOT's construction Activities. It should be noted that
Harris Creek has headwater tributaries that start in the main business and residential areas of central Rolesville. A decent
amount of shopping center and suburban subdivision development has picked up pace in the watershed. Due to this
increased impervious area and associated stormwater output, Harris Creek now has characteristics of a "flashy" urban
stream. This has resulted in numerous areas where banks have eroded significantly, as seen in Picture 4.
Picture 4.

In many areas, the residential developments have occurred right up near the stream. A few large neighborhoods can be
seen built right up against the stream buffer area, with very steep slopes down to the stream along with some associated
erosion. An example can be seen in Picture 5.
Picture 5.
Another notable feature both upstream and downstream of NCDOT's project is the alignment of a sewer easement owned
by the City of Raleigh. The easement, of course, have cleared all woody vegetation in its path, resulting in some parts
being quite muddy and soil eroding in some parts. The easement runs parallel to much of the stream, plus some crossings
as well. In many places along the stream, the easement and its access road shows significant steep slopes right onto the
streambanks and some associated erosion, and is depositing sediment into the stream. These can be seen in Pictures 6 -7.

;r manhole at top of steep slope.)
Picture 7.

Another significant indicator of sediment in the watershed was seen at NCDOT's own culvert. The culvert for Harris
Creek was built with baffles inside. Over time, small deposits of sediment are supposed to fill in these baffles to mimic
the meandering of a natural stream channel and to facilitate aquatic life passage. This is the intended and approved
design. Depending on local soil types, this is a process expected to take a period of several years. However in this
watershed the baffles in this culvert are filled up with sediment much sooner than normal, in less than two years. This is
shown in Picture 8. This indicates that, upstream from the project, the stream is migrating a large amount of sediment
from other sources that have eroded as shown in the previous pictures.
Picture 8: Sediment from upstream filling up baffles inside culvert at Site 8.
Given all these indications in the field both upstream and downstream of NCDOT"s project, it was very difficult to
pinpoint a single source of sediment that has accumulated down at Upchurch Lake. The entire watershed seems to be a
situation mixed with growing development encroaching on the buffers and streambanks along with easily erodible soils.
As with all transportation projects, DWR recommends that NCDOT remain diligent to maintain all sediment and erosion
control devices and to add seeding and mulch to cleared areas as much as possible. To date, NCDOT has no violations on
this project. Everything observed along the watershed of this site seems to indicate that sediment from the construction of
this NCDOT project was not the cause of this sedimentation issue. There are many variables contributing to the sediment
build up at Upchurch Lake and there appears to be no indication that NCDOT is at fault.
cc: Donald Pearson, NCDOT Roadside Environmental
Chris Murray, NCDOT Division 5 Environmental Officer
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