Streams and Creeks
What Is a Stream?
Figure 2 Stream Systems
A stream or creek is a body of water with surface water flowing within the bed and banks of a channel. Flow is controlled by surface and subsurface inputs, which can vary widely seasonally and between periods of rainfall. There are three types of streams (See Figure 3):
- Perennial streams, the largest type, have water flowing year-round
- Intermittent streams experience seasonal flows
- Ephemeral streams flow only during and immediately after rain events
You can follow the flow of water from its origins upstream. Just as a tree’s structure can “flow” from smaller twigs to larger branches, creeks function similarly with smaller tributaries (twigs) joining together to form larger creeks and streams (branches). See Figure 2 to get a better idea of how flows relate to each other in a stream system.
Figure 3 Types of Streams
Who Regulates Streams?
Ephemeral streams are the only type of creek solely regulated by the Town.
All intermittent and perennial streams are regulated under federal law and administered by both the United States Army Corps of Engineers (USACE) and the North Carolina Department of Environmental Quality (NCDEQ). The water quality is protected by the Clean Water Act as administered by the Environmental Protection Agency (EPA) and the State. Stream floodplains are regulated by the Federal Emergency Management Agency (FEMA) with support from the State and Town.
The riparian area adjacent to streams is also regulated by the State and implemented through the Town to protect Jordan Lake. The EPA and the State regulate the water quality of Jordan Lake and its entire watershed, in part by setting limits on the amount of nitrogen and phosphorus entering the creeks that feed the lake. The Jordan Lake Rules were in development for a number of years before being adopted in 2007 and have since been undergoing further review.
Why Are Streams Regulated?
This question could be answered from a legal perspective, which would get into 70 years or more of legislation and regulations! But the simple answer is that streams are regulated because prior to regulation, waterways were severely polluted. This interfered with the water cycle (Figure 4), and contributed to flooding, sediment build-up, erosion and run-off. These impacts have an adverse effect on people, plants and animals – the entire ecosystem.
Figure 4 Water Cycle
How Do I Care For a Stream on My Property?
Though any stream flowing through your property and the larger creek or watershed is regulated by federal, state and local governments, the care of the creek channel and its buffer is your responsibility as the property owner.
A common concern for property owners is woody debris, the trunks, limbs and branches in a waterway. Larger accumulations are referred to as large woody debris (LWD).
Under normal conditions, LWD is a natural and important part of aquatic ecosystems and is not a problem. It provides food and cover for fish and insects that become food for larger animals, and it creates pools that are desirable habitats. LWD also offers erosion control and adds physical structure to banks and channel bottoms. In many cases, LWD can and should be left alone.
However, when too much woody debris accumulates, it can collect trash, alter how water flows, and present an obstacle for recreational enjoyment. When LWD disrupts flow patterns, increases erosion, poses a hazard or blocks structures such as culverts or bridges, property owners should:
- Determine if you need a permit to do the work. You don’t need a permit to manage floating debris and logs that aren’t embedded in the stream bottom or banks. Felling trees along a creek bank or removing embedded debris may require a permit from the NC Department of Environmental Quality and the Army Corps of Engineers. The Town’s Stormwater Team can help you determine what approvals you need.
Minimize disturbance of the surrounding habitat areas.
Remove just enough debris to address the issue or concern and maintain the benefits provided.
Utilize the debris when appropriate to benefit the stream, including re-orienting the wood or anchoring it to the bank or within the channel.
If debris needs to be relocated, move it high enough and far enough away from the channel so it won’t re-enter with high flows.
Be mindful of surrounding habitat and minimize disturbance of these areas while conducting needed maintenance.
- Options for Backyard Stream Repair (Cooperative Extension)
- Natural Stream Processes (Cooperative Extension)
- Small-scale Solutions to Eroding Streambanks (Cooperative Extension/NC Forest Service)
- Video: Backyard Stream Repair (Cooperative Extension)
- Video: Stream Bank Stabilization Project (Cooperative Extension)
- Video: Managing Erosion with Plants (Cooperative Extension)
- Stream Restoration (NC Forestry Service)
- Stream Restoration (USDA-Natural Resources Conservation Service)
- Carrboro Creeks