DOI: 10.7910/dvn/dxogxq
title: Replication Data for: U.S. EPA National Rivers & Streams Assessment

description: What is the National Rivers and Streams Assessment?
&lt;br /&gt;&lt;br /&gt;
The National Rivers and Streams Assessment (NRSA) is a national probability-based survey of rivers and streams based on physical, chemical and biological data collected and analyzed using standardized field and laboratory methods.
&lt;br /&gt;&lt;br /&gt;
The goals of the NRSA are to determine the extent to which rivers and streams support a healthy biological condition and the extent of major stressors that affect them. The survey supports a longer-term goal: to determine whether our rivers and streams are getting cleaner and how we might best invest in protecting and restoring them. Additionally, the survey compares the condition of streams to those of earlier surveys.
&lt;br /&gt;&lt;br /&gt;
NRSA sampling field seasons were conducted in 2008-2009, 2013-2014, and 2018-2019.
&lt;br /&gt;&lt;br /&gt;
Survey Design
Sampling locations are selected using a modern survey design approach called a probability-based sample design. In such a design, every element in the population has a known probability of being selected for sampling. This important feature ensures that the results of the survey reflect the full range in character and variation among flowing waters across the U.S. Site selection rules included weighting to provide balance in the number of river and stream sites from each of the size classes. Site selection is also controlled for spatial distribution to make sure sample sites are distributed across the U.S.
&lt;br /&gt;&lt;br /&gt;
The NRSA assesses the ecological condition of the full range of flowing waters in the conterminous U.S. (lower 48 states). The target population includes the Great Rivers (such as the Mississippi and the Missouri), small perennial streams, and urban and non-urban rivers. Run-of-the-river ponds and pools are included, along with tidally influenced streams and rivers up to the leading edge of dilute sea water.
&lt;br /&gt;&lt;br /&gt;
View more details about the survey design in the design documents.
&lt;br /&gt;&lt;br /&gt;
The use of standardized field and laboratory protocols for sampling across all 48 states included in the NRSA is a key feature of the survey. It allows the data to be combined to produce a nationally consistent assessment.
&lt;br /&gt;&lt;br /&gt;
Indicators
National Rivers and Streams Assessment (NRSA) collects data on key indicators of biological, chemical and physical condition. These indicators are used to assess ecological and condition and to examine conditions that may negatively influence or affect stream condition (i.e. stressors). The NRSA uses fish and benthic macroinvertebrates (insects and other small animals such as snails and crayfish) as biological indicators of ecological condition. Stressors are the chemical, physical, and biological components of the ecosystem that have the potential to degrade biological integrity. Some of these are naturally occurring, some result only from human activities, but most come from both sources. Examples include chemical indicators such as nutrients and physical indicators such as streambed sediments or instream fish habitat. The NRSA also assesses indicators related to human health.
&lt;br /&gt;&lt;br /&gt;
If you have questions about the underlying data stored here, please contact Kaundinya, Pranav Shankar (pskaundinya@gmail.com). If you have questions or recommendations related to this metadata entry and extracted data, please contact the CAFE Data Management team at: climatecafe@bu.edu.
description: National Rivers and Streams Assessment Survey Results
description: The disclaimers below were copied as is from the EPA Disclaimers site (https://www.epa.gov/web-policies-and-procedures/epa-disclaimers): "Disclaimer of Endorsement Mention of or referral to commercial products or services, and/or links to non-EPA sites does not imply official EPA endorsement of or responsibility for the opinions, ideas, data, or products presented at those locations, or guarantee the validity of the information provided. Mention of commercial products/services on non-EPA websites is provided solely as a pointer to information on topics related to environmental protection that may be useful to EPA staff and the public. Copyright Status The U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce these documents, or allow others to do so, for U.S. Government purposes. These documents may be freely distributed and used for non-commercial, scientific and educational purposes. Commercial use of the documents available from the EPA websites may be protected under the U.S. and Foreign Copyright Laws. Individual documents on the EPA website may have different copyright conditions, and that will be noted in those documents. Disclaimer of Liability With respect to documents available from the EPA website, neither the United States Government nor any of their employees, makes any warranty, express or implied, including the warranties of merchantability and fitness for a particular purpose, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Exit Disclaimer The Exit icon denotes that you are leaving the EPA website and entering an external link or a third-party site. EPA's official web site is www.epa.gov. EPA has provided this link because it provides additional information that may be useful or interesting and is being provided in a manner consistent with the intended purpose of the EPA website. Please note that EPA uses third-party sites to provide EPA content already on www.epa.gov in a different format. EPA cannot attest to the accuracy of non-EPA information provided by these third-party sites or any other linked site. EPA is providing these links for your reference. In doing so, EPA does not endorse any non-government websites, companies or applications. Also, please be aware that the privacy protection provided on the EPA.gov domain (EPA Privacy and Security Notice) does not apply to these third-party sites. To learn more about EPA and social media, please refer to& our social media page. Notice Information from the EPA website resides on numerous computer systems funded by the Agency. The use of the EPA websites may be monitored for computer security purposes. Any unauthorized access to the EPA website is prohibited and is subject to criminal and civil penalties under federal laws including, but not limited to, Public Law 99-474, the Computer Fraud and Abuse Act of 1986. Terms of Use for Geospatial Data These geospatial data and corresponding cartographic materials have been approved for use by the U.S. Environmental Protection Agency (EPA) as advised by the EPA Geospatial Advisory Committee (EGAC). This approved release is on the condition that neither the EPA nor the U.S. Government may be held liable for any damages resulting from its authorized or unauthorized use. These data and any corresponding products, services, or materials do not necessarily represent the EPA’s official position or viewpoint, expressed or implied. These content items are not intended for use in establishing liability or calculating cost recovery statutes of limitations. They cannot be relied upon to create any rights, substantive or procedural, enforceable by any party in litigation with the United States or third parties. Additionally, although these data have been processed successfully on EPA computer systems, no warranty expressed or implied can be made regarding the accuracy or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The Agency reserves the right to revise EPA-stewarded datasets pursuant to further analysis and review without public notice. Unless otherwise specified, geospatial data produced by the EPA is by default in the public domain and is not subject to domestic copyright protection under 17 U.S.C. § 105. Referenced data from non-EPA sources are neither inherently verified nor independently tested by the Agency in all circumstances. Permission to reproduce copyrighted items not produced by the EPA must be secured from the copyright owner. EPA strongly recommends careful attention be paid to metadata files associated with these data to better understand limitations, restrictions or intended use. The U.S. EPA shall not be held liable for improper or incorrect use of the data."