Various types of sediments and rocks were analyzed for the relationship between hydraulic conductivity (K) and scale of measurement No variations of K with scale were observed for homogeneous media such as quartz‐arenites (quartz sandstones). However, hydraulic conductivity increased with scale of measurement in heterogeneous media. The scaling behavior can be described with the equation K = c (V)m, where c is a parameter characteristic of the geological medium that relates to geological variables such as average pore size and pore interconnectivity in porous media, and probably fracture opening and fracture interconnectivity in fractured media. V is the volume of tested material (used as scale measure), and m is the exponent of the relationship (slope of the line on a log‐log plot). The value of the exponent depends on the type or types of flow present. Porous flow media have an exponent of 0.5, multiple flow media an exponent between 0.5 and 1.0, and fracture and conduit flow controlled media an exponent of about 1.0. The more dominant fracture/conduit flow is relative to porous flow, the closer the exponent is to 1.0. K increases with scale up to a rock volume after which the aquifer approaches the properties of an equivalent homogeneous medium and K remains constant with scale. This volume (upper bound of the relationship) is related to the degree of heterogeneity in a medium. It is at a much larger scale in karstic media (if encountered at all) than in nonkarstic and more homogeneous media. Both confined and unconfined aquifers exhibit a similar scale dependence.

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Past studies in the Baton Rouge, Louisiana area considered streamwater quality during storm events but ignored water quality during low flow periods. This study includes determination of streamwater quality during low flow time periods for none watersheds in East Baton Rouge Parish, Louisiana. These samples were collected during dry-low flow periods as indicated by water levels at USGS stream gauging sites for each stream. Chemical analysis for ions was completed using colorimeters and gravimetric analysis for total dissolved solids (TDS) and total suspended solids (TSS). Land use appears to impact concentrations of ions, TDS and TSS in a variety of ways during periods of low flow. The two most rural watersheds, which are mainly underdeveloped, have higher concentrations of Fe and Mn. By contrast the three most urban watersheds, that are mainly commercial, industrial or residential, have higher concentrations of Si, SO4 and TDS.

Ground‐water interaction with lakes is often difficult to document because of both its diffusiveness and its spatial and temporal variability; reproducible measurements can be difficult to obtain. This paper takes advantage of the construction of a major drain stress in an aquifer system proximal to Lake Michigan to examine ground‐water/lake interactions in a complex hydrogeological setting. At the time of the measurements, the tunnel (4 to 8 m in diameter, 13 km in length, 1 to 3 km inland, and constructed in a low conductivity unit within a layered, fractured dolomite aquifer) had produced drawdowns of up to 50 m in the aquifer. In turn, the resulting trough of depression was inducing over 1600 m3/day (425,000 gpd) of water to flow from the lake to the tunnel. Seepage meters have been deployed over 40 km2 of the lake bed to define the extent of the tunnel's impact. The results show that seepage through the lake bed is a combination of downward flow toward the tunnel and lateral inflow generated by recharge events in shallow unconsolidated sediments. Downward seepage is detectable to more than 2 km offshore, so an average of over 20 m of clay‐rich glacial deposits and 10 m of dolomitic shale (both with hydraulic conductivities < 3 × 10‐8 m/sec) does not isolate the lake from the aquifer. Seepage meters have proven to be a viable and cost‐effective means to provide an accurate spatial distribution of ground‐water/lake exchanges over a large area.