Assessment & Monitoring Methods Flashcards
7 cards from real CSM practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Assessment & Monitoring Methods flashcards as text
Which parameter is measured by a totalizing flow meter in a stormwater monitoring program?
Answer: Cumulative volume over a storm event
A totalizing flow meter accumulates and records the total volume of flow passing through the monitoring point over the duration of a storm event.
What is the primary purpose of using a Manning's n roughness coefficient in stormwater assessment?
Answer: Calculating open-channel flow velocity
Manning's n is a roughness coefficient used in the Manning's equation to calculate flow velocity and discharge in open channels and pipes.
During a field assessment, you observe a V-notch weir in a detention pond outlet. What does the angle of the notch primarily affect?
Answer: Sensitivity of flow measurement at low flows
Narrower V-notch angles increase sensitivity and accuracy at low flow rates, while wider angles accommodate higher flows.
A stormwater manager needs to assess the condition of a buried culvert without excavation. Which method is most appropriate?
Answer: CCTV pipe inspection
Closed-circuit television (CCTV) inspection allows visual assessment of culvert interior condition, defects, and blockages without excavation.
What does an elevated Chloride (Cl⁻) concentration in stormwater runoff most likely indicate in a northern US climate?
Answer: Road salt application from winter maintenance
Road deicing salts contain sodium chloride or calcium chloride, and elevated chloride levels in stormwater are a common indicator of winter road salt use.
Which sampling strategy collects individual discrete samples at fixed time intervals regardless of flow conditions?
Answer: Time-composite sampling
Time-composite sampling collects aliquots at set time intervals (e.g., every 15 minutes), independent of the actual flow rate during the storm event.
What is the significance of the 'first flush' phenomenon in stormwater monitoring?
Answer: Initial runoff typically carries the highest pollutant concentrations
The first flush effect describes the tendency for the initial portion of stormwater runoff to carry disproportionately high pollutant loads accumulated during dry weather periods.