2.3 Best Management Practices (BMPs) in Action MCQ

A town plans to cut NPS pollution reaching a lake. They can afford only one BMP this year. Which choice best prioritizes actions using evidence about how BMPs control pollutants?

• Install source reduction measures like reducing available pollutants first

• Focus on transport controls like slowing stormwater movement only

• Rely on end-of-pipe remediation like chemical treatment alone

• Split resources thinly across all three BMP categories equally

A town detects rising mercury levels in a nearby lake, yet no factories discharge directly into the water. Using the hydrologic cycle, which pathway most plausibly explains how mercury concentrations increased in fish?

• Evaporation removing contaminants leaving mercury behind

• Upstream dilution by clean tributaries reducing mercury

• Direct seepage from deep aquifers bypassing surface flow

• Atmospheric deposition onto rainfall then runoff to lake

A county plans to reduce stream pollution by focusing on activities only within city limits along the riverbank. Evaluate this plan using the watershed approach and choose the best revision.

• Increase treatment only at the main river outfall pipe

• Coordinate across entire drainage area crossing jurisdictions

• Restore habitat solely in the city’s central park reach

• Test water quality quarterly without changing land uses

A town plans a new subdivision on former forest. Which integrated strategy best reduces nonpoint source pollution while maintaining natural watershed hydrology?

• Riprap-lined channels directing flow to a single outfall

• Low-Impact Development using dispersed vegetated conveyance

• Maximizing parking lots with high-capacity storm sewers

• Curb-and-gutter drains with a large detention pond

A watershed currently has 8 percent impervious cover. Planners expect new roads and roofs to raise it to 14 percent. Which paired actions most strategically limit runoff volume and pollutant loads from the added impervious area?

• Increase pipe sizes and deepen the detention basin

• Cluster buildings, preserve riparian buffers, add bioretention

• Straighten channels and armor banks with concrete

• Widen streets, remove trees, and speed surface drainage

A city block redevelops a large parking lot that frequently sends oily runoff into a nearby stream. The budget allows only one major retrofit this year. Which single structural BMP would most strategically reduce nonpoint source pollution while maintaining on-site stormwater treatment and is feasible within an urban footprint?

• Unlined detention pond without pretreatment forebay

• Dry well accepting direct runoff from traffic lanes

• Open grassed swale replacing perimeter sidewalks

• Large infiltration basin requiring wide setback area

• Bioretention area with underdrain in recessed islands

A homeowner’s septic system began backing up after they installed a garbage disposal and started pouring bleach-based cleaners down the drain. Which combined action plan best addresses the root causes while preventing leach field damage?

• Plant deep-rooted trees near the leach field for soil stability

• Install a larger tank and increase water use to flush solids

• Stop using the disposal, switch to non-chlorine cleaners, and repair leaks

• Pump the tank annually and add septic additives monthly

You are advising a neighbor whose lawn borders a small pond and who wants a lush lawn with minimal runoff. Which strategy set balances turf goals with water quality protection?

• Replace native shrubs with non-native ornamentals and increase pesticide use

• Irrigate daily regardless of rainfall and aerate annually

• Maintain a 100-foot vegetated buffer, test soil, and use slow-release fertilizer only if needed

• Apply quick-release fertilizer monthly and mow very short

A town plans a short road-repair project next to a stream on a steep slope. Which strategy best limits sediment transport during frequent summer storms while equipment is on-site?

• Hose paved areas daily to clear dust

• Divert runoff to storm drains without filtering

• Leave bare soil and sweep sediment weekly

• Install silt fencing upslope and seed after leaving

A marina wants to reduce nutrient and pollutant inputs from routine boat maintenance and visitor facilities. Which combined practice is most effective?

• Use phosphate‑free cleaners and provide pumpout

• Sand hulls over water and ban restroom access

• Wash with detergents in-lake and skip engine care

• Install dish‑only detergents and ignore runoff