Experts split over Meadowview hydrology: applicant expert says added streamflow helps Barker Creek; critics warn recharge and thermal risks

Meadowview hydrologic and stormwater design drew contested expert testimony during oral cross-examination and rebuttal at the Kitsap County hearing on Jan. 13, 2025. The applicant’s retained consultant, J. Scott Kindred, testified that his analysis finds small increases in runoff to Island Lake and modest additional flow to Barker Creek, and he supported the project’s approach to convey and disperse stormwater. Appellants’ experts challenged those conclusions, saying the record lacks the fine-scale hydrogeologic analysis needed to judge effects on the Island Lake aquifer, Barker Creek baseflow and stream temperatures.

The applicant hired Kindred to evaluate hydrologic concerns raised earlier in the matter. Kindred said he visited the site on Feb. 5, 2024 and submitted a technical report (admitted as Exhibit B‑10) and a written testimony package (Exhibit B‑11). He described his credentials as a professional engineer and licensed hydrogeologist and said his work focused on whether the proposed subdivision’s dispersion trenches and stormwater ponds would change groundwater recharge, creek flows or lake levels.

Kindred testified his December 11, 2024 report was essentially the same as a March 2024 draft except for one change: he removed a recommendation to maximize on-site groundwater recharge and instead endorsed routing additional average flow toward Barker Creek because, he said, the net ecological benefit to Barker Creek (fish habitat) outweighed a small reduction in recharge. He estimated the project would raise average annual runoff to Island Lake by about 1.4 inches across the lake surface (roughly 4 acre‑feet per year), increase peak winter flows in Barker Creek at one modeled location from about 0.13 cfs to 0.32 cfs, and raise small summer flows from roughly zero to ~0.02 cfs. He also reported a reduction in groundwater recharge of about 0.055 cfs — which he converted to about 40 acre‑feet per year (roughly 11,000,000 gallons/year). Kindred said dispersion trenches would discharge into permeable “advanced outwash” sands under the north/west portions of the site and argued the detention/dispersion approach would reduce erosive peak flows while increasing average flow where it can benefit fish.

Appellants’ witnesses disputed key assumptions underlying Kindred’s conclusions. Dr. Robert Rosin, a water resources and stormwater specialist, said the record lacks the finer‑scale hydrogeologic and geomorphologic analysis needed to conclude the aquifer beneath the site drains to Clear Creek rather than contributing to Barker Creek baseflow. Rosin warned the project’s reliance on under‑drained detention ponds and under‑drained bioretention could warm runoff before it reaches Barker Creek. He pointed to Department of Ecology and EPA studies showing retention ponds frequently raise runoff temperature, and he cited monitoring that found pond discharge above fish “upper‑optimum” temperature thresholds a large fraction of the time. “The retention pond has has, really pushes us out of our up to optimum limit,” Rosin testified, and he said ponds plus underdrains provide minimal thermal damping compared with infiltration.

Rosin also contested the applicant’s selection of stormwater controls under Kitsap County’s list‑approach (List 2). He testified the county manual’s priority is on-site dispersion and infiltration first; he said the Meadowview design starts with ponds and under‑drained bioretention instead of exhausting on‑site dispersion/infiltration options. He recommended more dispersed infiltration (bioswales, dispersion trenches, permeable pavement where feasible) to retain water as shallow interflow (beneficial baseflow and cooler water) rather than converting a large fraction to surface discharge through ponds.

Independent hydrogeologist Mr. Lubisher (testifying for appellants) gave related testimony. He reviewed regional studies going back to the 1980s and two USGS peninsula‑scale models (1998 and 2014–2016) and said those regional contours are too coarse for local flow‑direction decisions at the Meadowview site. Lubisher emphasized uncertainty about whether shallow interflow from the project area contributes to Barker Creek or drains toward Clear Creek/a regional flow path. He calculated the reported reduction in recharge (on the order of 11–13 million gallons per year by his conversion) is not trivial relative to the 30 million gallons per year that Silverdale Water District historically pumps into Island Lake in summer months, and he said that scale of change could meaningfully affect lake and creek baseflow. Lubisher recommended a finer‑scale numerical groundwater model (MODFLOW) and a site‑to‑aquifer water‑balance that includes long‑term well hydrographs to test the likely direction and magnitude of groundwater redistribution.

Both appellants’ experts also urged more detailed stream channel analysis. Rosin said Meadowview’s downstream analysis in the drainage report was brief and did not examine reaches with existing culverts, crossings and vulnerable channel geomorphology; he recommended a Level‑2 downstream geomorphic analysis to test whether a modeled ~300% increase in average runoff to a local headwater segment (as represented in one comparison) would affect channel stability, substrate and fish habitat.

Where the record stands: Kindred’s testimony and report conclude the Meadowview stormwater design will increase average flows to Barker Creek and reduce modeled recharge, but he judged the tradeoff acceptable and not likely to cause measurable harm. Appellants’ experts say the conclusions rest on regional maps and a surface model without the local hydrogeologic resolution, that the estimated reduction in recharge is large enough to warrant concern, and that detention‑to‑pond approaches risk warming water and changing habitat. Both sides urged the hearing examiner and agencies to rely on finer‑scale data (local hydrographs, updated contouring and a local groundwater model) before finding the risks negligible.

Ending: The hearing continued with further witnesses and scheduling discussions. Appellants and county staff said follow‑up analysis and possible public comments remain pending; both sides flagged the same core technical tradeoffs: infiltration and cooler baseflow versus managed discharge and localized increases in surface streamflow.