Stream Quantification Tool

Linking stream restoration activities with improvement to stream functions.

Though stream restoration efforts have increased in the U.S. over the past few decades, stream restoration practitioners and resource agencies have struggled to quantify the feasibility and ultimate success of restoration projects. A key challenge is linking stream restoration activities with improvement to stream functions. 

Quantifying Gained and Lost Stream Functions

The Stream Quantification Tool (SQT), based on the Stream Functions Pyramid Framework, was created to fulfill the following needs:

  • To provide

    To provide a spreadsheet calculator to determine the numerical difference, as measured using regionally specific metrics and reference curves, between an existing (degraded) stream condition and the proposed (restored or enhanced) stream condition. This numerical difference is known as functional lift or uplift and is often used to assist in calculating stream credits as defined by the 2008 Federal Mitigation Rule.

  • To ensure

    To ensure parity between debits and credits, a Debit Calculator was adapted from the SQT that is capable of quantifying functional loss from common development activities such as culverts, impoundments, and channelization. When used together, the SQT and Debit Calculator can provide certainty that debits are being offset with function-based credits.

  • To incentivize

    To incentivize high-quality stream restoration and mitigation by matching restoration goals with each site’s restoration potential. The SQT can provide greater certainty to agencies, mitigation providers, and the public that restoration activities proposed at a certain site will deliver intended benefits for years to come.


Getting Started with the SQT

If you’re new to the SQT, the following are links to useful introductory materials. 

  • NC Stream Quantification Tool v3.0 - This is the QT populated with performance standards from NC streams. If you are interested in using the QT in another state, send me a note ([email protected]) and I'll let you know which parameters and performance standards need to be changed.
  • SQT Spreadsheet User Manual - A user document on how to enter data and operate the SQT

  • SQT - Data Collection and Analysis Manual - A user manual on how to collect and analyze field data in preparation for use with the SQT. This document includes the catchment assessment form and a rapid-assessment field form. 

  • NC Quantification Tool v 3.0 Example - This version has been populated with a fictional project to demonstrate how the QT works. It includes reach-scale restoration with a BMP on an adjacent ephemeral tributary.
  • List of Metrics - The Workbook includes a list of all the parameters and measurement methods with their corresponding performance standards. The performance standards are shown as min and max values for each functional category (functioning, functioning-at-risk, and not functioning) along with notes. The stratification methods are also provided for each measurement method. Finally, each performance standard includes a source reference.
  • Frequently Asked Questions