Wet Detention Ponds Research Articles

Nutrient and Fecal Coliform Discharge from Coastal North Carolina Golf Courses

AbstractWater quality investigations were conducted at five golf courses in southeastern North Carolina to determine levels of pollutants contributed by the courses to adjacent coastal streams. In general, nitrate levels were greater in streams leaving the courses compared with streams entering the courses, but concentrations varied considerably among courses. Ammonium concentrations increased in passage through most of the courses. Orthophosphate concentrations were elevated on midcourse sites on two courses, but were low in the outflow water except at one course. The golf courses studied were not significant sources of fecal coliform bacteria to nearby waterways; in fact, passage through some courses served to reduce coliform loads entering from upstream suburbs. Recent rainfall and fertilization application influenced outfall nitrate concentrations only at some courses. Landscape management practices appeared to play a critical role in determining nutrient concentrations in the outfall and at midcourse sites. Nutrient addition bioassay experiments conducted in one of the coastal creeks receiving golf course effluent demonstrated that nutrient concentrations as low as 50 to 100 µg nitrate N L−1 were capable of causing significant phytoplankton biomass increases. Nitrate levels in the outflow streams were at or above concentrations causing significant increases in phytoplankton biomass in our bioassay experiments. These coastal creeks host spring and summer algal blooms; thus, some golf course discharge nutrient concentrations are at levels great enough to contribute to eutrophication problems in estuarine waters. Vegetated buffer zones, wet detention ponds, and wooded wetland areas led to considerably lower nutrient output than sites lacking such management practices and should be used whenever possible to protect nutrient‐sensitive receiving waters.

Storm Water Pollutant Removal by Two Wet Ponds in Bellevue, Washington

Two wet detention ponds were investigated for their ability to remove pollutants, primarily phosphorus, from storm water runoff. The two ponds lie within the Phantom Lake watershed, a subbasin of the Lake Sammamish watershed in Bellevue, Wash., which is developed as a commercial and residential area with impervious surface area as high as 57%. There are design differences between the two ponds, yet both are comparable to design recommendations set forth by local agencies. One pond was built for flow attenuation and water quality treatment; the other serves only to improve water quality. Fifteen storms and two baseflows were successfully sampled during the Northwest's wet season from October 1996 through March 1997. Pollutant removals varied between one-fifth and one-half for phosphorus, and greater than one-half for total suspended solids and most of the analyzed metals. Removal efficiencies were consistently better in the pond designed primarily for water quality.

Effect of In-Lake Water Quality on Pollutant Removal in Two Ponds

An extensive field study examined pollutant removal in two regional wet detention ponds near High Point, N.C. Substantial differences in influent pollutant concentrations between the ponds caused significant differences in pond water quality and pollutant removal efficiency. In Davis Pond, influent fecal coliform and nutrient concentrations were high because of several large dairy farms in the watershed, resulting in hypereutrophic conditions as evidenced by high chlorophyll-a concentrations, high midday pH values and supersaturated midday oxygen concentrations. In Piedmont Pond, influent fecal coliform and nutrient concentrations were much lower, resulting in mesotrophic to slightly eutrophic conditions. Both ponds thermally stratified and developed an anaerobic hypolimnion. In Davis Pond, annual pollutant removal efficiencies for total suspended solids, volatile suspended solids, total organic carbon, total phosphorus, dissolved phosphorus, nitrate/nitrite, total ammonia nitrogen, and total nitrogen were 56%, 32%, 15%, 41%, 54%, 16%, 2%, and 11%, respectively. In Piedmont Pond, annual pollutant removal efficiencies were 20%, 30%, 27%, 40%, 15%, 66%, -64%, and 36%, respectively.

Discussion: Systematic Evaluation of Pollutant Removal by Urban Wet Detention Ponds

Discussion: Systematic Evaluation of Pollutant Removal by Urban Wet Detention Ponds

Closure to “Systematic Evaluation of Pollutant Removal by Urban Wet Detention Ponds” by Jy S. Wu, Robert E. Holman, and John R. Dorney

Closure to “Systematic Evaluation of Pollutant Removal by Urban Wet Detention Ponds” by Jy S. Wu, Robert E. Holman, and John R. Dorney

Influence of particle size on wet pond effectiveness

A 5 670‐m2 wet detention pond draining a predominantly residential urban area was monitored for flow, suspended solids, bedload, particle‐size distribution, and selected pollutants during 16 storm events. Both suspended solids concentrations and particle‐size distribution of the suspended solids in runoff water exhibited large variations between storms. Though a portion of particles larger than the pond's critical particle size left the pond, the pond removed 87% of the total suspended solids entering the pond. The relative proportion of clay‐size particles increased from 36 to 72%. Sand‐ and silt‐size fractions both decreased. Heavier particulate material saltating along the channel bottom, termed bedload, composed an average of 14% of the total particulate mass or load to the pond. The pond's sediment and associated pollutant removal efficiencies were influenced by influent particle‐size distribution.

Systematic Evaluation of Pollutant Removal by Urban Wet Detention Ponds

Three urban wet detention ponds in the Piedmont of North Carolina were monitored to investigate long-term pollutant removal as a function of surface to area ratios. Eleven storm events were monitored over a sampling period of 13 months. Urban runoff originating from the study area was characterized by event-mean concentrations for total suspended solids (135 mg/L), total Kjeldahl nitrogen (0.88 mg/L), total iron (6.11 mg/L), and total zinc (66 ug/L). Concentrations of copper and lead were consistently below the detection limits of 30 ug/L and 100 ug/L, respectively. The observed event-mean concentrations were generally lower than the national values reported by the Nationwide Urban Runoff Program. Particle sizes of sediment discharged in runoff were much finer than the national averages due to the predominant clayey soils in the region. This study demonstrates that surface to area ratio can be a useful predictor of wet pond performance. Utilizing 1--2% of the watershed area for the development of wet detention ponds at strategic locations could reduce pollutant loadings to meet targeted requirements of water quality improvement.

Modeling and impact of metal accumulation in bottom sediments of wet ponds

Data from thirteen sites located in south and central Florida were used to evaluate the heavy metal accumulation in the bottom sediments of wet detention ponds. Accumulation rates were calculated for cadmium, chromium, copper, iron, nickel, lead and zinc. Copper, zinc and lead accumulations account for 75 percent or more of the total heavy metal accumulation, excluding iron. Relative accumulation rates for copper, zinc and lead averaged 1:4:8:11.8, respectively. Linear and non-linear predictive equations based on the ratios of total drainage are to pond surface area were developed for copper, lead and zinc accumulation rates. The impact of sediment heavy metal content on benthic organisms was evaluated for nine of the study ponds. Benthic organisms in the bottom sediments showed less species diversity than typical freshwater lakes and copper appeared to be the most detrimental metal to benthic organisms.

INTEGRATED URBAN STORMWATER QUALITY MANAGEMENT: FIELD INVESTIGATIONS ATA BEST MANAGEMENT FACILITY

Stormwater discharges from urbanized areas strongly contribute to the impairment of water uses in a number of Areas of Concern in the Great Lakes Basin, and may impede efforts to delist these areas from the Remedial Action Plan program. In a search for solutions to these problems, an interdisciplinary team from the National Water Research Institute and Queen’s University is conducting field-scale research (supported by laboratory studies) designed to characterize stormwater contaminants and their removal by an integrated environmental system centred around an existing stormwater best management facility, an on-line wet detention pond. This facility is appropriate because it is typical of many older ponds: it is on-line, its inadequate size and unfavourable shape prevent effective stormwater quantity and quality control, and it discharges to a downstream sensitive coastal wetland area. The main objective of the research is to develop a combination of cost-effective, operationally-simple methods of providin...

Treatment systems for urban and highway run-off in Denmark

To observe the required quality in Danish receiving water systems, pollution from urban and highway run-off is of importance in many cases. There is therefore a potential demand for treatment of the wet-weather flow. An evaluation of relevant treatment methods was carried out for the National Agency for Environmental Protection. The wet detention pond was considered the most efficient and suitable solution for removal of the most important pollutants, i.e. phosphorus and heavy metals, in the storm-water run-off from urban catchments and highways. Recommended design procedures are described and exemplified in this paper.

Sediment accumulation in detention or retention ponds

Accumulation of bottom sediments in nine highway wet detention ponds in central to south Florida were investigated. Sediment core samples were collected at each pond and were later analyzed in the laboratory. In-situ measurements of accumulated loose sediment depths above the parent soil in each pond were recorded. Existing models were used to calculate removal efficiency of suspended solids and to estimate the depth of accumulated sediments in each pond. Attempts were made to correlate measured and calculated sediment accumulation rates and the surrounding drainage area.

Lagoons and ponds

Lagoons and ponds

Potential contamination of groundwater from Cu, Pb, and Zn in wet detention ponds receiving highway runoff

Heavy metals (Cu, Pb, Zn) in highway runoff entering detention ponds are removed by physical, chemical and biological processes, and concentrate in the bottom sediments. Soluble metal fractions percolate into the bottom sediments and produce a potential for contamination of groundwater. Therefore, a two-year research project was supported by Florida Department of Transportation (FDOT) and Federal Highway Administration (FHWA) to study the fate and migration of those metals in bottom sediments of six wet detention ponds, located in Florida. Sorption, molecular dispersion, and pilot studies were conducted from these ponds. The results showed that the flow of metals through the bottom sediments is a very slow process. Most of these metals are retained in the top 15-20 cm of sediments and saturation of this layer may take years. Removal of accumulated bottom sediments at time intervals averaging 25 years would be sufficient to minimize the potential contamination of groundwater. Also existing models were modified to simulate metal transport through the bottom sediments in wet detention ponds.

Two Dimensional Numerical Modeling of Hydrodynamics and Pollutant Transport in a Wet Detention Pond

A vertically averaged two-dimensional hydrodynamic model was developed to simulate water movements in a small shallow unstratified impoundment. The hydrodynamic model was then coupled with a two-dimensional pollutant transport model to calculate the mass fluxes of pollutant. The differential equations were numerically solved on a space staggered grid using a two-level time ADI integration scheme. The model was used to simulate the flow and pollutant transport and to assess the pollutant removal performance of an urban detention pond located in Charlottesville, VA. Results of the simulation were compared to field data taken at the site. The model was successfully utilized in simulating pollutant transport and trapping, making it useful in analyzing wet detention pond modification for urban pollution control.

PHOSPHORUS REMOVAL BY URBAN RUNOFF DETENTION BASINS

ABSTRACT An empirical model previously developed for predicting phosphorus retention in reservoirs is tested against the urban lake/detention pond data set. Detention pond design criteria developed under the EPA's Nationwide Urban Runoff Program (NURP) are ovaluated using the model. For summer precipitation and runoff quality typical of St. Paul, Minnesota, a basin designed according to NURP criteria is estimated to have a long-term-average phosphorus removal efficiency of 47–68 percent. For a given loading regime, phosphorus removal is shown to be more sensitive to pond depth than to surface area. Specific design features for enhancing phosphorus removal (deepening, promoting infiltration, promoting plug flow, and chemical treatment) are discussed. The methodology can be used to evaluate wet detention pond design criteria in other regions, with substitution of appropriate precipitation and runoff quality characteristics.