tmdl_au: Oregon TMDL database by assessment unit

In DEQcdonald/odeqtmdl: Oregon TMDL database

Oregon TMDL database by assessment unit

Description

Inventory of Oregon TMDL information summarized by Assessment Unit (AUs). See tmdl_au_gnis for TMDL information summarized for each named stream in watershed assessment units and tmdl_reaches for TMDL information summarized for each NHD reach.

Usage

data(tmdl_au)

Format

An object of class data.frame with 35819 rows and 25 columns.

Details

Note the TMDL information is still being assembled and is undergoing review. Some information may not be accurate. See each relevant TMDL document for the official record and more information. TMDLs developed by tribal governments are not included at this time. The inventory is still being developed and some information may not be accurate. A full listing of all non-tribal TMDL actions in Oregon can be viewed using tmdl_actions.

NHD values are derived from NHDH_OR_931v220, which is the current version used for DEQ business data. Database fields include:

• action_id: EPA ATTAINS Action ID assigned to each TMDL document.

• TMDL_wq_limited_parameter: Name of the water quality limited 303(d) parameter that the TMDL addresses.

• TMDL_pollutant: Name of TMDL pollutant causing the water quality impairment.

• TMDL_scope: Provides information about how the TMDL applies.

  • TMDL: The TMDL was developed to address a 303(d) listing or future listing in this assessment unit.

  • Allocation only: A TMDL allocation applies in this assessment unit but the TMDL does not address a 303(d) listing or future listing. Typically this situation is applicable for tributaries or canals that are upstream of the reach where the "TMDL" applies. The pollutant reduction in the upstream reach is needed to achieve the TMDL loading capacity of the downstream reach.

  • Advisory allocation: A TMDL allocation may be applied at the discretion of DEQ, per TMDL language, based on assessment of source loads and if pollutant reduction is needed to achieve a TMDL allocation or loading capacity downstream. See TMDL document for details. The TMDL does not address a 303(d) listing or future listing in this assessment unit.

• Period: Identifies the fish use period that the TMDL addresses. Only used for TMDLs that address temperature or dissolved oxygen.

  • year_round: TMDL addresses only non spawning (year round) uses for temperature or dissolved oxygen water quality standards.

  • spawning: TMDL addresses only spawning uses for the temperature or dissolved oxygen water quality standards.

  • Both: TMDL addresses both spawning and non spawning (year round) uses for temperature or dissolved oxygen water quality standards.

  • Mixed: TMDL addresses different fish use periods in different sections of the assessment unit.

• Source:

  • Point source: Identifies assessment units where pollutant loading is from point sources only.

  • Nonpoint source: Identifies assessment units where pollutant loading is from nonpoint sources only.

  • Both: Identifies assessment units where pollutant loading is from point sources and nonpoint sources.

• Pollu_ID: DEQ water quality parameter ID. ID is for the parameter in 'TMDL_wq_limited_parameter'.

• HUC6: Basin six digit USGS hydrological unit code

• HUC6_Name: USGS Basin name.

• HUC6_full: Concatenation of the HUC6 and HUC6_Name fields.

• HUC8: Subbasin six digit USGS hydrological unit code.

• HUC8_Name: USGS Subbasin name.

• HUC8_full: Concatenation of the HUC8 and HUC8_Name fields.

• HUC10: Watershed ten digit USGS hydrological unit code.

• HUC10_Name: USGS watershed name.

• HUC10_full: Concatenation of the HUC10 and HUC10_Name fields.

• AU_ID: Assessment Unit ID.

• AU_Name: Name of the assessment unit

• AU_Description: Assessment unit descriptions

• TMDL_length_km: Length of the assessment unit in kilometers where TMDL_scope = 'TMDL'. Length is calculated using the linear flowline feature in Albers Equal Area projection.

• Allocation_only_km: Length of the assessment unit in kilometers where TMDL_scope = 'Allocation only'.

• Advisory_allocation_km:Length of the assessment unit in kilometers where TMDL_scope = 'Advisory allocation'.

• AU_length_km: Length of the entire assessment unit in kilometers. Length is calculated using the linear flowline feature in Albers Equal Area projection.

• TMDL_AU_Percent: Percent of the assessment unit where a TMDL has been developed to address a 303(d) listing or future listing.

• Allocation_AU_Percent: Percent of the assessment unit where a TMDL allocation applies.

Examples

db1 <- data(tmdl_au)
db2 <-odeqtmdl::tmd_au

DEQcdonald/odeqtmdl documentation built on Feb. 9, 2025, 10:13 a.m.