Trutta Environmental Solutions

HDSS Overview

Access to clean water is fundamental to a heathly life. Clean water for drinking, bathing, watering crops, and supporting recreation and wildlife is critical to our happiness and well-being as a society. While it is obvious we need clean water, the same water flowing in our streams and rivers is facing a multitude of issues that degrade water quality and impair stream health and as a result decrease our quality of life. According to the U.S. Environmental Protection Agency, these issues include increased amounts of:

• Point and non-point source pollution,
• Municipal wastewater and storm water runoff,
• Agricultural runoff of sediment, fertilizers and pesticides,
• Channelization, construction and land development,
• Water withdrawls, barriers, and habitat modification,
• Removal of riparian vegetation, and streambank destabilization.

These water quality problems result in higher water treatment and delivery costs, more water use restrictions and drought impacts, increased flood damage and the need for flood risk mitigation, and the loss of instream habitat and increasing number of Threatened and Endangered Species.

Improving water quality is no small task. It is common for many different issues to impair water quality and stream health at a single location and conditions vary at upstream and downstream locations. Addressing these issues is best approached from an integrated planning and management framework where each problem is identified and coordinated actions to improve stream conditions are determined. Fundamental to understanding the issues and wisely developing actions, is having high quality data of the current conditions in the river corridor. The new High Definition Stream Survey (HDSS) method can be used to collect detailed river corridor surveys over long (many mile) stream segments much more rapidly and cost effectively than traditional survey methods. The results of an HDSS effort are highly valuable for stream channel assessments, water quality and quantity studies, habitat assessments, community outreach and overall integrated watershed planning (Figure 1).

Figure 1. The application of the HDSS data to multiple different water management issues and its use in an integrated planning framework.

In contrast to the continuous coverage of long stream segments provided by the HDSS approach, traditional stream sampling surveys are based on point samples or descriptions of short (several 100m) sections of streams or rivers. These traditional methods collect information on a small percentage of total aquatic habitats and then extrapolate the findings between sampling sites to fill in the gaps. It is not uncommon for a few-hundred-meter survey site to be considered representative of 20 or more miles of adjacent stream. Extrapolation of data is a major source of error and will completely miss problems if the problem areas fall outside of a sample location. The HDSS method avoids the problems of data extrapolation by collecting a continuous survey of the entire river segment allowing the location, extent, and intensity of problems areas to be accurately identified (Figure 2).

Figure 2. An example of good and bad streambank conditions. These two sites are located about 1 mile apart on the Big Canoe Creek, AL. These images highlight the variability of conditions throughout a stream and the difficulty of choosing a sampling location that accurately reflects stream conditions as a whole.

At the heart of the HDSS method is the ability to gather a wide range of stream corridor information at a consistent spatial resolution (Figure 3). This means that documentation of stream corridor conditions is rapidly and consistently applied to very long stream segments which results in contiuous measurements and not in highly detailed measurements at one location with no information gathered for miles in either direction, a big limitation of traditional survey methods. The HDSS method not only delivers a more complete data set than traditional surveys, but is also less expensive. HDSS methods require fewer people and less time in the field, greatly reducing costs. The speed of data capture and lower costs when using the HDSS method allow for greater distances of river to be surveyed. HDSS  methodology can be used to gather important indicators of stream condition in wadeable and non-wadeable streams, providing more consistent and broadly applicable results while still collecting the data at a greater speed.

Figure 3. HDSS gathers information from the front, both sides, and down while recording time and location every second. This rapid approach provides consistent spatial resolution data for long stream segments and is far more efficient and effective than traditional transect approaches.

The HDSS method is an outgrowth of research efforts at the University of Tennessee. The rapid, multi-attribute, geo-referenced techniques have been tested and used for delineation of streambank erosion potential (Connell 2012), development of sediment TMDLs (Hensley 2014), mapping of aquatic habitats (Candlish 2010, McConkey 2010, Connell and Parham 2015), comparing thawleg and cross-sectional transect approaches (Swinson 2012), and prioritizing restoration areas (Connell and Parham 2014). The method has been used successfully on numerous streams and rivers including Big South Fork River, TN (McConkey 2010), Obed River, TN (Candlish 2010), Beaver Creek and the New River, TN (Connell 2012), Paint Rock Creek, AL (Connell and Parham 2014), Bear Creek, AL (Connell and Parham 2014), Turkey Creek, AL (Connell and Parham 2015), Manoa, Palolo, Makiki, Waiawa and Iao Streams, HI (Parham 2015) and many others.

The HDSS method is used to rapidly collect, classify, and analyze important stream corridor data over long segments of streams and rivers. In general, the HDSS method follows a standardized series of steps that promotes rapid, systematic collection and processing of large amounts of river condition information (Figure 4). The specifics of the data collected may vary with the project’s requirements, but following the basic HDSS process ensures a successful project.

Figure 4. Standard HDSS project flow chart. Systematic data collection and processing supports high quality project results.

While HDSS is a new approach to stream and river surveys, the technology to make it work exists and the method has been proven to work. Field techniques and data management processes are in place to accomplish:

  • Point and Non-Point Pollution Documentation
  • Water Quality Assessment & Water Quantity Allocation Support
  • Streambank Stability & Erosion Potential Analysis
  • Habitat Mapping & Habitat Suitability Modeling
  • Hotspot Prioritization
  • Infrastructure & Barrier Assessments
  • Project Impact, Mitigation & Monitoring
  • Community Outreach & Virtual Tour Capabilities

HDSS provides powerful insight into the current conditions of a stream or river and is a more effective approach to documenting stream corridor conditions than traditional sampling approaches. HDSS provides the data necessary for wise water resource planning and management.