Lago Vista City Council on Oct. 2 tabled consideration of a contract amendment with Garver Engineering that would add design and construction‑administration work for rebuilding process basins and TLAP irrigation work for the city’s wastewater expansion, citing newly raised structural concerns and uncertain permit requirements.

Council paused the amendment after Garver told the council that record drawings and subsequent structural review suggest two existing process basins (an aeration basin and an aerated sludge holding tank) and one clarifier likely fall short of current concrete design standards. Garver said that, rather than retrofitting uncertain concrete conditions, rebuilding those process basins would be the safer long‑term approach. The proposed amendment the council considered would have added engineering scope that Garver estimated at about $1,864,090 and increased the expected construction cost estimate from roughly $29 million to as much as $47 million if the basins are rebuilt.

Why council paused: Garver said its visual inspection initially suggested the basins could be reused, but a later review of original record drawings and concrete specifications flagged low PSI mixes, unclear water‑cement ratios and inadequate rebar sizing/spacing for water‑bearing structures under ACI 318/350 standards. Garver told the council that retrofit options (for example adding buttresses or plates) are not favored by its structural engineers and that a replacement design would require additional geotechnical borings, revised sequencing and an extra 12 months on top of the original construction duration.

Third‑party review ordered: Council unanimously voted to table the amendment and asked staff to arrange an independent structural review — including consideration of rehabilitation options versus full rebuild — and return to council at the city’s second November meeting. Council also asked staff to solicit options for reducing onsite inspection staffing hours to lower the professional‑services price if feasible.

Permitting and TLAP (irrigation) work: Garver’s amendment would also add survey and design of additional TLAP (treated‑effluent land application) irrigation areas at Cedar Breaks, and a contingency for a new 40 acre‑foot pond if TCEQ requires it. Garver said the TCEQ review of the city’s major amendment to increase permitted flow to 1.5 MGD is ongoing and could take roughly six to 12 months; the pond work was offered as an “if required” additive and would be priced separately. Garver recommended designing infrastructure that preserves future tertiary filters (type‑1 reuse) as an additive alternate so the city can opt in at bid time.

Cost context presented to council: Garver gave column estimates showing a conventional new plant cost in the region of roughly $30–45 per gallon (conventional activated‑sludge projects), noting small expansions can be surprisingly expensive when much of the plant infrastructure must be replaced. Garver estimated a tertiary filter/polishing package (to produce type‑1 reuse) in the neighborhood of $4–5 million as an additive alternate, and said a rebuild that includes two new aeration basins, a new sludge tank and dewatering building could move the total project closer to $45–47 million.

Council direction and next steps: Council instructed staff to (1) obtain an immediate independent structural engineering opinion on the basins and rehabilitation possibilities; (2) return with an updated recommended scope and revised amendment that reflects any agreed scope reductions; and (3) report timeline options and risk mitigation measures (including temporary rental/packaged capacity options and sequencing to avoid permit noncompliance). Councilman Shane Roberts asked that staff also explore cost‑reducing options and competitive alternatives if Garver’s revised fee remains high.

Why it matters: The plant expansion would raise permitted capacity from 1.0 MGD to 1.5 MGD to meet future growth; it also involves regulatory interactions with TCEQ on required storage (acre‑feet) and options to move toward type‑1 reuse to offset required TLAP land. The structural findings, if confirmed, increase scope, cost and schedule risk — hence council’s request for an independent review before committing city funds.

What the amendment proposed (summary): Garver’s amendment would add design for demolition and replacement of two process basins and a clarifier, a new return‑activated‑sludge (RAS) pump station, dewatering building design, additional construction administration and geotechnical borings, and TLAP design and survey for Cedar Breaks, with a not‑to‑exceed engineering amendment of $1,864,090. Construction was estimated in briefing slides at roughly $29 million under the reuse scenario and up to $47 million for full rebuild.

Quotations: “We don’t feel it’s safe to move forward with these basins,” Jeff Meadows, Garver’s Central Texas facility lead, told council. “We found rebar sizing, spacing and wall thickness that are a concern for the structure.” Lanita McCauley Bates of Accenture, speaking earlier at the meeting on P3 delivery options, told council there are multiple delivery approaches and emphasized performing a clear value‑for‑money screen before selecting a public‑private delivery option.

What council asked staff to deliver: a third‑party structural review focused on rehabilitation options vs full rebuild; a revised, narrower engineering amendment if possible; options for inspection staffing reductions; a recommended plan and timeline that preserves regulatory compliance (TCEQ) and the city’s procurement options.

Ending: Council’s decision to pause the amendment reflects concern about committing the city to the higher cost path without independent verification of the structural risks Garver identified. Staff will return with the third‑party review and revised recommendation at the second November meeting.