THE PITFALLS of

PERMITTINGA Guide to Navigating the

Texas Surface Water Quality Standards for TPDES Discharge Permits

By Lili Murphy

Administrative: Need the Info

• USGS map• Location of site• Correct HIGHLIGHTED discharge route• Discharge route description to segment

• Outfall coordinates (Lat/Long)

Location, Location, Location:Outfalls & Discharge Routes

• Know your receiving waters• Flow status• Baseflow• Baseline water quality

• Characteristics• Concerns• Impairments• TMDLs

Flow Status & Presumed Uses

• Presumed uses are based on flow status• 30 Texas Administrative Code §307.4(h) and (l) of the 2014 Texas Surface Water Quality Standards

(TSWQS) & Procedures to Implement TSWQS (IPs)• Presumed uses have associated criteria to support those uses• Intermittent streams presumed to support a minimal aquatic life use• Intermittent with perennial pools (limited)• Perennial (high)

• Beware of perennial streams with a low base flow: TDS, dissolved oxygen, nutrients• Beware of springs: high quality, sensitive waterbodies with low baseflow, typically have ES

Critical Conditions & Dilution

• Intermittent streams: no dilution, only acute criteria apply, no mixing zone

• Beware intermittent with pools: no headwater flow, acute & chronic criteria apply, potential fishery

• Beware of perennial streams with low baseflow: minimal dilution, acute & chronic criteria apply, potential fishery and human health

Watershed Protection Rules

• Watershed Protection Rules are proscribed in 30 Texas Administrative Code 311

• Procedures to Implement the Texas Surface Water Quality Standards• Includes waterbodies in the Trinity, Colorado, San Jacinto and Bays & Estuaries• Benbrook has recently been added to Subchapter G

• Requirements for discharges in specified watersheds can include phosphorus limits, advanced treatment of carbonaceous biochemical oxygen demand (CBOD) and ammonia-nitrogen, and prohibitions of discharge except by irrigation.

Edwards Aquifer Rule 30 TAC 213

• Table 3 of the IPs lists the classified segments that cross the contributing and recharge zones of the southern section of the Edwards Aquifer.

• Requirements for discharges can include phosphorus limits, advanced treatment of carbonaceous biochemical oxygen demand (CBOD) and ammonia-nitrogen, and prohibitions of discharge except by irrigation.

• These requirements vary according to location of the plant in the contributing or recharge zones, and distance to the recharge zone.

Endangered Species

• Screening for Endangered Sp. can be found starting on Pg. 21 of the Ips

• Appendix B. Locations of Federally Endangered and Threatened Aquatic and Aquatic-Dependent Species in Texas (Ips)

• State listed species• Proposed listings

• May require additional permit limits• Dechlorination• Daily average ammonia-nitrogen limit < 3.0 mg/L• Additional limits may be imposed based on USFWS concerns

303 (d) Listed Waterbodies & Texas Integrated Report

• Typical constituents currently listed for impaired uses• Bacteria• Depressed D.O.• TDS, sulfates, chlorides• PCBs, pesticides, • Dioxin• Impaired aquatic communities• pH• Mercury, copper

• Antidegradation Policy-cannot contribute to loading of listed constituents

• Total Maximum Daily Loads-Limits loading of constituents of concern

Worst Case Scenarios: Nutrients

• Nutrient limits are based on screenings for the potential of eutrophication• Total phosphorus limits are primarily recommended for freshwater waterbodies• Total nitrogen limits to protect seagrasses and sometimes freshwater• Actual nutrient limits are determined on a case-by-case basis

• Scenarios likely to require nutrient limits• Springs or recharge features• Perennial streams with low baseflows• Intermittent streams that flow into pools, ponds, lakes or impoundments• Coves or transition zones in reservoirs• Clear waterbodies with bedrock or cobble substrate and little canopy or trees• Seagrasses

Worst Case Scenarios: TDS

• Major Municipal Permits > 1.0 MGD

• Large discharges into small, perennial streams with low baseflow

• Intermittent streams that flow into pools, ponds, lakes or impoundments

• Be aware of water sources and contributions to TDS like groundwater & industries

Worst Case Scenario: Dissolved Oxygen

• Perennial streams with a low base flow and high aquatic life use• Streams that are intermittent with pools with a high aquatic life use• Lake back waters• Overlapping impact zones• Deep pools• 303 (d) waterbodies impaired for low D.O.• Non-tidal slow moving bayous• Watersheds with multiple discharges• Ver large discharges

Be a Good NeighborProblematic Discharge Routes

• Intermittent stream into downstream neighbors’ amenity lakes

• Small creeks with minimal baseflow into neighbors’ on-channel swimming holes

• Spring-fed endangered species habitat

• Recharge features, aquifer

• Stream or river with private wells along discharge route

• Public water supply intake structures

Welcome to Austin!(or what’s left of it)

• Threadgills AKA Armadillo Headquarters (Barton Springs Road & Riverside)

• Continental Club on S. Congress

• Shady Grove on Barton Springs Road

• Barton Springs on Barton Springs Road across from Zilker Park

• Ladybird Lake