Stream Protection Priorities for WRAPS
Go to Section:- Overview
- Data Quality
- Data Organization
- Coordinate System
- Attributes
- Distribution - Get Data
- Metadata Reference
Section 1: Overview
Originator: Streams Protection Prioritization Committee; Minnesota Department of Natural Resources; Minnesota Pollution Control Agency
Title:
Stream Protection Priorities for WRAPS
Abstract:
Restoring impaired waters is expensive, difficult, and may require a long time frame for success. Protecting streams and rivers that are currently healthy is far more cost-effective than restoring lost health and function. This data provides a prioritization for protecting stream reaches that are currently supporting the aquatic life designated use as determined by fish and/or invertebrate community assessments.
Purpose:
A prioritization of healthy stream reaches for development and implementation of protection strategies. The highest priority is given to those stream reaches that are at greatest risk of becoming impaired while also recognizing that stream quality varies amongst the stream categories in the tiered aquatic life use or TALU framework. Therefore, top priorities may vary between nearly impaired and highest quality depending on local input and/or region of the state.
Time Period of Content Date:
08/22/2022
Currentness Reference:
New data will be added to the dataset on an annual basis, as new aquatic life assessments are completed.
Progress:
In work
Maintenance and Update Frequency:
Annually
Spatial Extent of Data:
State of Minnesota
Bounding Coordinates:
-97.23
-89.53
49.37
43.5
Place Keywords:
Minnesota
Theme Keywords:
water resources;
river reaches;
surface water quality;
environmental assessment;
multivariate statistical analysis;
Theme Keyword Thesaurus:
USGS Thesaurus
Access Constraints:
Access is Not Restricted
Use Constraints:
Please read accompanying doc: Minnesota DNR Data and Software License Agreement.pdf
Contact Person Information:
Kevin Krause,
Research Scientist
Minnesota DNR - Ecological and Water Resources
500 Lafayette Rd
Saint Paul,
MN
55155
Phone: 651-259-5167
Email: Kevin.P.Krause@state.mn.us
Associated Data Sets:
Assessed Waters, Minnesota, 2018 (Proposed);
Current Stream Water Units in Minnesota (MPCA)
Section 2: Data Quality
Attribute Accuracy:
Logical Consistency:
Attribute values are tested to ensure they are within valid value ranges and codesets. Analysis outputs are checked for logical consistency and spot checks are used to validate the analysis methods.
Completeness:
The stream protection priorities data reflects information gathered through aquatic life assessments that are collected as part of the intensive monitoring phase of the 10-year WRAPS plannning cycle. The stream protection prioritization data includes streams that have been assessed for support of aquatic life since 2014, when MPCA adopted the TALU framework for aquatic life assessments.
Horizontal Positional Accuracy:
Lineage:
This data set is based on streamlines maintained within the 24,000 National Hydrography Dataset (NHD). The spatial data represents the status and extent of WIDs at the time each watershed was last assessed according to MPCA’s IWM schedule. WID modifications such as splitting into multiple WIDs or merging with adjacent WIDs that have occurred since the HUC 8 watershed was last assessed are not represented in this coverage.
The following steps outline the analysis process used to derive the stream protection prioritization class:
1. Identify Healthy Stream Reaches for Protection Prioritization
1.1 Select stream reaches designated as 'Fully Supporting for Aquatic Life' (FS_AqL);
2. Identify FS_AqL stream reaches that are close to the impairment threshold
2.1 Apply threshold for TALU designation as modified, general or exceptional
3. Identify Conditions and Risk Factors Predictive of IBI Scores
3.1 Select riparian and watershed-wide conditions that predict degraded stream communities.
3.2 Select riparian and watershed-wide conditions that predict healthy stream communities.
4. Rank selected stream reaches within each HUC 8 Major Watershed by:
4.1 'Nearness' of IBI scores to impairment threshold
4.2 Riparian and watershed risk level
4.3 Riparian and watershed protective conditions
4.4 Stratify rank by TALU designation as modified, general or exceptional
Step One: Identify High Quality Stream Reaches for Protection Prioritization
Stream reaches are assessed by MPCA to determine if they are Fully Supporting for Aquatic Life based on fish and/or invertebrate Index of Biotic Integrity (IBI) results, water chemistry data, TALU designation, and expert review. A fully supporting stream reach meets the habitat and lifecycle needs of aquatic biota expected to be present. For this reason, FS_AqL was used as the criteria to identify stream reaches to be considered for implementation of protection strategies.
Step Two: Determine Healthy Stream Reaches Close to the Impairment Threshold
For FS_AqL stream reaches, those with IBI scores near the impairment threshold for their respective TALU class were identified and used in the prioritization process. A stream reach was considered close to impairment if the average deviation of IBI scores across the stream assessment unit or AUID (within MPCA's 10 year assessment window) was less than five points from the threshold. The average deviation was calculated separately for fish and invertebrate IBI scores.
Step Three: Identify Conditions and Risk Factors Predictive of IBI Scores
Watershed factors that impact stream health were evaluated across three spatial scales - near stream, riparian corridor and upstream contributing watershed - for three test watersheds.
GIS analysis was conducted to quantify a suite of factors at three spatial scales for all stream reaches in the test watersheds. The results were evaluated by a biometrician to determine which had the strongest correlation to IBI scores.
Canonical correlation analysis was used to identify watershed factors that were best correlated with biological condition. This analysis allows examination of the watershed effects on all three biological metrics (fish IBI, invert IBI, & Minnesota Stream Habitat Assessment or MSHA) concurrently, and accounts for multicollinearity among explanatory variables.
The 'Corridor' scale was removed from the final list of factors because it provided no additional explanatory value than the near channel 'Riparian' factors alone. The following factors were selected as most predictive of IBI scoring results at the Riparian and Upstream Watershed scales:
Factors associated with riparian and watershed risk condition:
- Density of Roads
- Percent Disturbed Land
The amount of land in public ownership or permanent protective easement was selected as an estimation of area that presumably will not undergo significant land use changes, and thus provide an estimation of resiliency. Stream reaches with this protective strategy already in place are ranked as lower priority for further protection investment. However, the distribution of existing protected lands should be reviewed during the local prioritization process for unique opportunities such as creating habitat corridors, protecting sensitive resources or addressing headwater conditions.
Factors associated with riparian and watershed protective condition:
- Percent Protected Lands (public ownership/easements; see appendix)
STEP FOUR: Rank FS_AqL Stream Reaches
The approach developed for ranking FS AqL Stream AUIDs at the HUC8 watershed or statewide scale uses the following formula:
Protection Priority Rank = ((IBI Threshold Proximity) * (Riparian Risk + Watershed Risk + Current Protection))
where the top rank (3) represents a high priority and a low rank (27) represents a low priority, so that ranks should be sorted in ascending order to identify the highest priority protection streams (e.g., Table 1). For instance, a stream with both communities near their respective impairment thresholds, a high risk of degradation at the watershed and riparian scales, and a low percentage of land currently under protection at the riparian and watershed scales will have a high rank/low value; a top protection priority for the watershed.
Formula Inputs:
Riparian Risk
3 - Low Risk - Low density of roads and low percent disturbed land in riparian area
2 - Medium Risk - Both risk factors intermediate or one factor high and one low
1 - High Risk - High density of roads and high percent disturbed land in riparian area
Each risk factor is ranked - low (3), medium (2), or high (1) - based on a trisection of the data distribution of FS_AqL streams at the statewide scale. Riparian risk is the average of these two factors.
Watershed Risk
3 - Low Risk - Low density of roads and low percent disturbed land in watershed area
2 - Medium Risk - Both risk factors intermediate or one factor high and one low
1 - High Risk - High density of roads and high percent disturbed land in watershed area
Each risk factor is ranked - low (3), medium (2), or high (1) - based on a trisection of the data distribution of FS_AqL streams at the statewide scale. Watershed risk is the average of these two factors.
Current Protection (riparian & watershed scales)
3 - Low Risk - High percent of public and easement protected land in riparian and watershed area
2 - Medium Risk - Both protective factors intermediate or one factor high and one low
1 - High Risk - Low percent of public and easement protected land in riparian and watershed area
Each protective factor is ranked - low % protected (1), medium (2), or high % protected (3) - based on a trisection of the data distribution of FS_AqL streams at the statewide scale. The riparian and watershed scales are averaged to derive the current protection value.
IBI Threshold Proximity (= 'Community Nearly Impaired')
3 - Low Risk - Neither community IBI score (on average) is within 5 pts of their respective IBI threshold
2 - Medium Risk - Only one community IBI score (on average) is within 5 pts of its respective IBI threshold
1 - High Risk - Both community IBI scores (on average) are within 5 pts of their respective IBI threshold
Final Ranking of Reaches
Once ranks are calculated for each FS_AqL stream their protection priority for the watershed can be determined by their ascending order (lowest ranks = highest priorities) within their TALU tier. Depending on the circumstances it may be desirable to sort the rankings first by TALU class so that all exceptional use streams are a higher priority than general or modified use streams (e.g., Table 1) or, alternatively, to prioritize just using the risk-based rankings (Figure 4) regardless of TALU class (see Appendix D for examples).
Section 3: Spatial Data Organization (not used in this metadata)
Section 4: Coordinate System
Horizontal Coordinate Scheme:
Universal Transverse Mercator
UTM Zone Number:
15
Horizontal Datum:
NAD83
Horizontal Units:
meters
Vertical Datum:
Vertical Units:
Depth Datum:
Depth Units:
Section 5: Attributes
Overview:
Detailed Citation:
Table Detail:
Stream Protection Priorities| Field Name | Valid Values | Definition | Definition Source |
|---|
| wid | - | A unique stream reach identifier for a specified length and location of stream assessed by the Minnesota Pollution Control Agency. WIDs consist of the HUC8 ID plus a 3-digit water body identifier. | |
| reach_name | - | Name of stream reach associated with unique identifier. | |
| reach_desc | - | To-from description of stream reach location. | |
| reach_len_mi | 0.15 to 61.16 | Length of stream reach in miles. | |
| upst_area_smi | 0.91 to 5685.48 | The upstream area of the stream at the downstream point of the stream reach, in square miles. | |
| talu | enumerated | Tiered aquatic life use designation. Component of aquatic life and recreation designation as specified in water quality standards (Minn R. Ch 7050). | |
| exceptional | | |
| general | | |
| modified | | |
| vulnerable | enumerated | Aquatic life vulnerability designation. Whether or not the stream reach was designated during the assessment process as 'vulnerable' (=nearly impaired) based on best professional judgment. | |
| Y | Vulnerable | |
| N | Not Vulnerable | |
| cold_warm | enumerated | Whether the stream is designated/protected as a cold water vs warm water stream. | |
| cold | | |
| warm | | |
| rule_status | enumerated | Rule/draft status. | |
| draft | The designated aquatic life use (use_class) has been confirmed through a use attainability analysis but neither has it gone through a formal public comment period nor has it been adopted into Minnesota's water quality standards (Minn R. Ch 7050). | |
| rule | The designated aquatic life use (use_class) has been confirmed through a use attainability analysis, has gone through a formal public comment period, and has been adopted into Minnesota's water quality standards (Minn R. Ch 7050). | |
| comm_nearly | enumerated | Determined based on the status of both fish and aquatic macroinvertebrate IBI proximity determinations. | |
| neither | neither community is near impairment threshold | |
| one | one community is near impairment threshold | |
| both | both communities are near impairment threshold | |
| iwm_cycle | enumerated | MPCA's Intensive Watershed Monitoring Cycle that is the basis for the priority rank. The newest information is presented for WIDs that are fully supporting in multiple cycles. | |
| 1 | Priority ranking based on assessment conducted during cycle 1. | |
| 1.5 | Priority ranking based on special assessment between cycles 1 and 2 to evaluate channelized streams using TALU framework. | |
| 2 | Priority ranking based on assessment conducted during cycle 2. | |
| riparian_risk | enumerated | Riparian risk category based on two riparian risk factor ranks (road density and % disturbed). | |
| high | | |
| med/high | | |
| medium | | |
| med/low | | |
| low | | |
| watershed_risk | enumerated | Watershed risk category based on two watershed risk factor ranks (road density and % disturbed). | |
| high | | |
| med/high | | |
| medium | | |
| med/low | | |
| low | | |
| protection_level | enumerated | A characteristic of the contributing watershed determined by the proportion of land under public or protected ownership categories. | |
| high | | |
| med/high | | |
| medium | | |
| med/low | | |
| low | | |
| priority_rank | 3 to 27 | Overall rank for identifying priority streams in need of protection strategy development and implementation, the larger the rank the lower the priority. | |
| priority_class | enumerated | Letter grade approach to categorizing stream protection priorities based on a trisection of the possible range of ranks (3-27). | |
| A | High priority for protection | |
| B | Medium priority for protection | |
| C | Low priority for protection | |
| watershed_name | - | Watershed name, as defined by DNR Major (Level 04) watersheds. | |
| huc12 | - | Hydrologic Unit Code (12-digit) for the subwatershed. | |
| aggregated_huc12 | - | MPCA's aggregation of HUC 12s to approximate NRCS's old HUC 11 subwatersheds, used as a framework in the systematic selection of IWM monitoring stations. | |
Section 6: Distribution
Publisher:
Minnesota DNR - Ecological and Water Resources
Publication Date:
11/28/2018
Contact Person Information:
Zeb Thomas,
GIS Data Systems Coordinator
Minnesota DNR - GIS
500 Lafayette Rd
Saint Paul,
MN
55155
Phone: 651-259-5637
Email: zeb.thomas@state.mn.us
Distributor's Data Set Identifier:
env_stream_prot_prio_wraps
Ordering Instructions:
Please visit the download page for this dataset on the Minnesota Geospatial Commons website using the web link below (Online Linkage). Online Linkage: I AGREE
to the notice in "Distribution Liability" above. Clicking to agree will either begin the download process, link to a service, or provide more instructions. See "Ordering Instructions" above for details.
Section 7: Metadata Reference
Metadata Date:
08/22/2022
Contact Person Information:
Kevin Krause,
Research Scientist
Minnesota DNR - Ecological and Water Resources
500 Lafayette Rd
Saint Paul,
MN
55155
Phone: 651-259-5167
Email: Kevin.P.Krause@state.mn.us
Metadata Standard Name:
Minnesota Geographic Metadata Guidelines
Metadata Standard Version:
1.2
