Wastewater

Canyon Ranch Wastewater Issue
 
 
The Mystic Shores Property Owners Association is committed to keeping residents informed about the Canyon Ranch wastewater permit renewal and its potential impacts on our community, our natural resources, and our shared property assets. As development continues around Canyon Lake, wastewater management has become a critical issue for property owners where stormwater and groundwater systems are closely interconnected.
Concerns raised by residents, experts, and regional officials fall into four major areas:
  • Geology and Aquifer Vulnerability
Mystic Shores sits atop highly fractured karst limestone, where water — and contaminants — can move rapidly and unpredictably through underground channels. Effluent discharged into the dry creek behind existing homes and through Devils Hollow could enter these fractures, potentially affecting the Edwards and Trinity Aquifers and public and private wells downstream. This geological setting makes wastewater management uniquely sensitive in our region.
  • Wastewater Plant Deficiencies and Potential Impacts
Engineering reviews have identified preventable vulnerabilities in the Canyon Ranch wastewater plant design, including limited monitoring, lack of redundancy, generator reliability concerns, membrane risks, potential solids release, and the absence of a phosphorus‑precipitation step. These deficiencies increase the likelihood of untreated or partially treated effluent entering the environment during failures or storm events.
  • Cultural and Archaeological Resources
Devils Hollow and surrounding areas contain evidence of long‑term human habitation. To protect sensitive sites from vandalism, only general information is shared publicly. However, wastewater discharge, erosion, and sediment movement pose risks to these cultural resources, and the Conservation Committee continues to monitor developments in coordination with regional experts.
  • Phosphorus, Cyanobacteria, and Localized Bloom Risk
Phosphorus is the primary nutrient that fuels cyanobacterial (blue‑green algae) blooms, especially in warm, shallow, slow‑moving water. The proposed entry point in Mystic Shores is a dry creek, which normally carries no water at all. When treated effluent is introduced into a dry creek, it creates small, stagnant pools in low areas, depressions, and bends — conditions that are ideal for cyanobacteria growth.
 
Warm, shallow, nutrient‑rich pools — even at temperatures in the 70s — can support cyanobacterial growth and bloom formation. Blooms can produce toxins, strong odors, and surface scums, and may pose health risks to pets and people. These risks are highest in backyards and Devils Hollow, where water may linger, warm rapidly, and remain still.
 
Unlike deeper, circulating water in the Guadalupe River or Canyon Lake, the dry creek environment is far more susceptible to localized cyanobacterial blooms. Without a phosphorus‑removal step in the wastewater treatment process, nutrient buildup in these stagnant areas could significantly increase the frequency and intensity of blooms close to homes.
The POA and Conservation Committee are actively engaged on two fronts:
  1. The regulatory process through TCEQ, including preparation for the agency’s upcoming Responses to Comments and potential Contested Case Hearing.
  2. Public engagement through media outreach, expert briefings, letters to legislators, and community education.
How YOU can help
COMMENTS MADE "ON THE RECORD" AT TCEQ PUBLIC MEETING
Mystic Shores residents and many others commented at the public meeting. Those comments were transcribed here and summarized here.
 
PUBLIC RECORD ACCESS
Residents who wish to review submitted comments and official filings may search the TCEQ Commissioners’ Integrated Database (CID) - https://www14.tceq.texas.gov/epic/eCID/index.cfm?clear=Y
Use Permit Number: WQ0015866001
When searching:
Check the boxes labeled:
    • “Include all Filings on this Item”
    • “Include all correspondence from the public on this Item”
Then click Search below “Step Three” section.
 
 
 
Slide Shows:
 
Important Links:
Handouts from May 18 Meeting (and later)
Engage with Our Elected Officials 
Let them know why this issue is important to you so that they can help to advocate for you.
Jen Crownover - County Commissioner
Kristen Hoyt - County Judge
Carrie Isaac - Texas House of Representatives
Donna Campbell - State Senate, District 25