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South Atlantic Water Science Center

Charlotte-Mecklenburg Hydrologic Network

Streamflow Network

Background

The first site recording streamflow data in Mecklenburg County was 02146500 Little Sugar Creek, which was established in 1924. In 1962, the Charlotte Mecklenburg streamflow network expanded to five gaging stations:

  • 02146300 Irwin Creek near Charlotte (still operating)
  • 02146450 Briar Creek at Sharon Road (discontinued in 1974)
  • 02146500 Little Sugar Creek near Charlotte (moved to 02146507 in 1978)
  • 02146600 McAlpine Creek at Sardis Road (still operating)
  • 02146700 McMullen Creek at Sharon View Road (still operating)
wooden bridge and gaging station

Streamgage 02146500, Little Sugar Creek near Charlotte, circa 1934

In the early stages data collection was obtained by pen and ink strip chart gages, which were maintained during routine and event-specific site visits. By the 1970's, automatic digital recorders (ADR) were installed at some sites, suitable for input into a digital computer for the storage and computation of daily mean gage height and daily mean discharge. The collection of data still required a site visit and electronic translators were used to convert the record of paper punch-tapes to a digital file for computer storage of the data. This remained the primary method of data collection until the early 1990's when electronic data loggers were introduced using landline telemetry. Sites could be queried from a base station computer at regular intervals throughout the day. By 1997 there were 15 streamflow sites collecting 15-minute gage-height data every 4 hours continuously using phone modems.

wooden bridge and gaging station

Streamgage 02146507, Little Sugar Creek near Charlotte, with radio transmitter, circa 2000

wooden bridge and gaging station

Electronic Instrumentation at streamgage 02146507

The network grew steadily and by 2005, there were about 50 sites being polled hourly. Radio telemetry was introduced to the system which allowed the entire network to be polled every hour using ultrahigh frequency (UHF) line-of-site radios. By 2010, the radio network was improved upon using an improved protocol of radio communication which allows the entire network of sites to be heard from within a few minutes after each 5-minute gage-height reading is recorded at the site. As of today (2014) there are a total 54 streamgage sites which encompass 23 gaged watersheds.

Irwin Creek Rating Curve

Objectives

  1. Develop and maintain a real-time network of streamgages for Mecklenburg County to document current hydrologic conditions and extreme events
  2. Provide flow data to support water-quality sampling being conducted by Mecklenburg County Department of Environmental Protection and the USGS
  3. Provide data to develop and test flow models on selected stream reaches
  4. Provide data to develop and test rainfall-runoff models
  5. Support Mecklenburg County flood mitigation efforts by providing emergency managers with early notification of potential flooding conditions
  6. Evaluate methods and hardware, and apply software to improve retrieval and dissemination of data to interested users

Approach

  1. Locate, install, operate and maintain streamgages throughout Mecklenburg County at selected sites and critical flood-prone locations
  2. Develop stage-discharge relationships at selected streamgages
  3. Research and implement new advances in technology and hardware to improve the quality of the data, and the speed and efficiency of data dissemination to all interested users, including the public