Clarifier Surface Area for a Target SOR
The clarifier surface area a target surface overflow rate needs at the design flow.
Example
You enter
- Design flow (MGD) 1
- Target surface overflow rate (gpd/ft², ~700-1000) 800
You get
- Required surface area 1250 ft^2
- Equivalent circular diameter 39.89
Checked against published worked examples from: Mesabi Range College (MECC).
Details, formula, and sources
Scopearea = flow x 1e6 / SOR, plus the equivalent circular clarifier diameter. 1 MGD at 800 gpd/ft^2 needs 1,250 ft^2 (about a 40 ft diameter). Answers 'how big a clarifier' instead of the rate from one area; size below the limit for peak flow. A separate weir and solids check governs alongside. Ten States Standards; the state primacy agency governs.
Formula or tablerequired_area = flow x 1e6 / target_SOR (ft^2), the inverse of SOR = flow x 1e6 / area; equivalent circular diameter = sqrt(4 x area / pi).
Source and editionClarifier surface loading rate, standard wastewater-operations practice (Ten States Standards / Metcalf & Eddy), by name, solved for the area.
Free accessThe overflow-rate relation is a standard published wastewater result; the state design criteria govern the limits.
What governsEstimate. Operator of record and primacy agency govern.
API field namesflow_mgd, target_sor_gpd_ft2, required_area_ft2, equiv_diameter_ft
- Surface area for SOR required area = flow x 1e6 / target SOR (gpd/ft^2)wastewater operations
- Equivalent diameter circular clarifier diameter = sqrt(4 x area / pi)geometry
- Design limits state design criteria govern the actual ceilings; size for peak flowscope of this tile