Flower Mound Council approves water and wastewater master plan amendments ahead of impact‑fee update

Flower Mound’s Town Council unanimously approved amendments to the town’s Water and Wastewater Master Plans Tuesday, a step staff and consultants said is necessary to publish an updated impact‑fee report required by changes in state law.

The amendments, presented by town engineer Bob Pegg and consultant Connor Manley of Kimley‑Horn, revise demand projections, hydraulic models and a capital improvement program the town will use to calculate impact fees. Manley told council the consulting team calibrated models with meter locations, lift‑station data and treatment‑plant flows and then ran five‑, ten‑ and build‑out scenarios.

Why it matters: the update informs the impact‑fee calculation — a mechanism to ensure new development covers system capacity costs — and helps town leaders and developers understand when and where new water and sewer infrastructure will be needed.

Manley said the town’s potable system is projected to show a 9.5 million‑gallons‑per‑day (MGD) shortfall by build‑out in 2048 under current assumptions, down from a 14‑MGD projection presented in 2020. He added that reuse systems, once online, reduce projected deficit but do not eliminate it: with reuse modeled, the shortfall drops to roughly 6 MGD.

The consultant laid out capacity‑driven project costs: potable water projects of about $38.0 million inside the five‑year window and $41.4 million beyond it (about $79.3 million total), and wastewater projects of about $22.9 million inside five years and $58.4 million beyond (about $81.3 million total). Manley described the combined five‑year total as roughly $60.8 million and said the multi‑decade program approaches $100 million beyond five years; he cautioned these figures exclude potential Trinity River Authority expansion costs the town may be asked to share.

Council members pressed staff and the consultant on assumptions that led to a lower near‑term projection (8.4 MGD in the East system), with Manley and staff pointing to slower-than‑anticipated build‑out in Lakeside since 2020. Council also questioned how the model could run 'what‑if' scenarios if the legislature upzoned areas or changed allowable uses; staff said they can populate the model with alternate land‑use allocations, run the model, and cost resulting capital projects for interim legislative responses.

Town staff noted a recent change in state law requires impact‑fee updates on a three‑to‑five‑year cadence rather than annually; the amendment was presented to make the town’s master plans consistent with the impact‑fee process and to make the impact‑fee report publicly available. "This will allow us to release the impact fee report," Manley said during the presentation.

The council approved the two related agenda items by separate motions and unanimous roll calls. The votes were formal approvals of the plan amendments; the impact‑fee schedule itself will follow the publicly posted impact‑fee report and any additional proceedings required by state law.

What’s next: staff will post the impact‑fee report as described in the presentation and proceed with the impact‑fee process. Council and staff said the town will continue annual model updates and major plan amendments every five years; staff also said they intend to prepare fiscal analyses sooner if state legislative proposals re‑emerge.

Speakers quoted in this article are drawn from the council meeting transcript and include town engineer Bob Pegg and consultant Connor Manley. The council’s motion and roll calls are recorded in the official minutes and the items passed unanimously.