How to Size a Containerized MBR STP in Los Angeles (2026 Guide)

What a Containerized MBR STP Actually Delivers

A containerized membrane bioreactor (MBR) sewage treatment plant (STP) merges activated-sludge biology with submerged ultrafiltration (UF) membranes inside a standard ISO shipping container. Because the membrane retains biomass, the secondary clarifier is eliminated and effluent is essentially solids-free. MENA-Water and HUBER Technology both confirm that the membrane-activated-sludge process replaces the secondary sedimentation tank, allowing higher mixed-liquor concentrations and a much smaller footprint than conventional activated-sludge plants. The UF pore size sits in the 2–100 nm range per HUBER Technology, and Pure Aqua's MBR-C uses hollow-fiber PVDF UF at a 0.04 µm nominal pore size — small enough for MENA-Water's stated 99.9999% virus and bacteria reduction.

The standard form factor is a 20' or 40' high-cube (HC) ISO container, with Pure Aqua MBR-C building the bioreactor, membrane tank, fine-bubble diffusers, and an internal chemical cleaning system into the container shell. MENA-Water and HUBER Technology both report package plants scalable from a few m³/day up to thousands of m³/day, with up to 1200 m³/day of filtered effluent achievable in a single 40-foot ISO container. The 180 m³/day AO-MBR-MBBR unit dispatched by Qingdao Yimei on July 11, 2025 confirms the typical non-potable reuse target: greening irrigation and toilet flushing. SIGMADAF also markets containerized MBR as a decentralized, plug-and-play fit for residential developments, resorts, hospitals, and camps — exactly the Los Angeles use case this guide addresses. For a broader hardware overview, see this containerized wastewater treatment engineering guide.

Los Angeles Discharge and Reuse Rules That Drive the Spec

Before sizing any containerized MBR in Los Angeles, lock down the discharge and reuse pathway — the effluent quality target sets the membrane flux, the aeration tank sizing, and the bid price. California Title 22 sets the recycled-water criteria for non-potable reuse (irrigation, toilet flushing, cooling), and the criteria differ by reuse tier. Confirm the exact end-use with the Authority Having Jurisdiction (AHJ) before locking in the MBR specification, because a Title 22 irrigation-grade effluent is not the same as a Title 22 unrestricted reuse effluent.

For sites above the on-site wastewater treatment system (OWTS) threshold, the Los Angeles County Sanitation Districts (LACSD) Liquid Waste Management Section issues waste discharge permits. Residential HOAs and camp operations in the unincorporated LA County area typically cross that threshold, which means the containerized MBR is being permitted as a discrete-discharge system, not a private domestic well-and-septic system. Inside the City of Los Angeles, the Bureau of Sanitation OWTS and on-site wastewater rules govern small-flow sites, and site-specific conditions override generic manufacturer claims. Drought-driven LA water-reuse incentives make Title 22-compliant irrigation reuse financially attractive, so the design should default to irrigation-grade effluent unless the AHJ says otherwise.

The supplied research does not contain specific Title 22 numeric limits or LACSD permit fees, so do not assume values here. The engineer should request the latest Title 22 criteria for the chosen reuse tier, the current LACSD permit application package, and any City of LA OWTS overlay before final sizing. For the compliance frame on adjacent California projects, see this California Title 22 compliance guide.

Step 1 — Build the Design Flow From Occupancy and Fixtures

The design flow for a residential or camp project in LA starts with two numbers: design occupancy and per-capita wastewater generation. Pure Aqua's MBR-C population table anchors residential and light-commercial sizing at 50 gallons per capita per day, and that is the most defensible starting factor for an LA HOA or camp. Converting to metric: 50 gal ≈ 0.189 m³ per person per day, so a 100-person design occupancy produces an average daily flow of roughly 18.9 m³/day before any peaking or commercial loading.

For a residential HOA, count the dwelling units and apply a defensible persons-per-household value for LA — confirm the default with the AHJ's plumbing code, because persons-per-household is a local input, not a manufacturer value. Add a small commercial loading if the community has a clubhouse, pool, guardhouse, or maintenance building; the magnitude of that loading is site-specific and should be requested from the AHJ. For a camp, distinguish between residential-style occupancy (multi-week stays, near-constant flow) and transient occupancy (weekend or seasonal peaks) because the two patterns produce very different peaking factors even at the same average daily flow.

The supplied research does not give a specific per-capita flow value for camp vs. residential LA systems, nor a persons-per-household default for LA County. Treat the 50 gal per capita per day as an order-of-magnitude anchor, then ask the AHJ for the local per-capita and per-fixture-unit values before the bid goes out. The output of this step is a defensible average daily flow in m³/day that the rest of the methodology can build on.

Step 2 — Apply Peaking Factors and Convert to Container Count

Residential and camp flows are not flat — Saturday morning at a 50-unit HOA or check-in evening at a 200-person camp produces a peak hourly flow that can be several times the daily average. Apply a peaking factor to the average daily flow so hydraulic surges do not overwhelm the membrane tank; the exact factor must be confirmed with the AHJ. Once the design peak flow is set, convert it to a container count using the manufacturer's m³/day rating at the actual influent BOD/COD load.

For LA projects under roughly 50 m³/day, a single 20' HC unit is often the right starting point; above that, the design moves to one or more 40' HC units or parallel trains. MENA-Water's stated 1200 m³/day per 40-foot ISO container is the upper envelope for that form factor, and Pure Aqua MBR-C ships in both 40' and 20' HC depending on capacity. The table below frames the envelope the engineer is working inside; actual per-container ratings must be confirmed with the manufacturer because they vary with influent strength and effluent targets.

Peaking-factor values and per-container m³/day ratings vary by manufacturer and influent strength; request the manufacturer's specific curve for the actual BOD/COD load rather than assuming a generic benchmark. For a worked example of how the same per-capita logic plays out in a colder climate, see this containerized MBR sizing in cold-climate residential and camp projects reference.

Step 3 — Specify Pretreatment and Equalization

Undersized pretreatment is the most common cause of MBR fouling in camp and residential service, so the bid must spell out the upstream train before the container is selected. Pure Aqua MBR-C ships with a drum screen at 1.5 mm perforation as standard pre-treatment, and that screen is what protects the submerged hollow-fiber UF membranes from rag, hair, and large solids. Camps generate hair, lint, sand, and food solids; residential communities generate lint, wipes, and grease — both flows need screening matched to the dominant solids, with the AHJ's minimum screen aperture as the floor.

Equalization (EQ) is not always inside the container. For variable camp loads, an upstream buffer tank sized to the peak hour flow smooths the load on the MBR and protects the membrane from hydraulic shock. Confirm whether the chosen containerized MBR includes EQ or requires an external tank, and confirm the EQ sizing rule (hours of retention, m³ per m³ of daily flow) with the manufacturer as part of the bid package — the supplied research does not give a specific EQ sizing rule, so do not invent a number. A typical containerized MBR bid pairs the drum screen with an upstream EQ tank sized to the design peak hour, then a feed pump set that matches the membrane tank's nominal flux.

For the screening component, a drum screen pre-treatment unit specified at or below the AHJ's minimum aperture is the standard upstream guard. If the site is constrained on equalization footprint, the MBR supplier may offer an integrated buffer inside the container — confirm that as a line item in the bid rather than as a verbal assurance.

Step 4 — Work the Two LA Reference Scenarios

Two worked scenarios convert the methodology into something an LA consulting engineer or HOA board can hand to a bidder. Both scenarios use the 50 gal per capita per day Pure Aqua benchmark as the starting per-capita factor and convert to metric at 0.189 m³ per person per day; both must be re-run with the AHJ's approved values before going to bid.

Scenario A — 50-unit residential community. At roughly 3 persons per unit, design occupancy is on the order of 150 people. Average daily flow is 150 × 0.189 m³ ≈ 28 m³/day. With a residential peaking factor, the design flow climbs into the band where a single 20' HC containerized MBR typically covers the load, subject to manufacturer confirmation. Effluent target is Title 22 irrigation-grade for on-site landscape irrigation, so the treated water offsets at least part of the community's landscape water budget.

Scenario B — 200-person camp at peak weekend occupancy. Average daily flow is 200 × 0.189 m³ ≈ 38 m³/day, but with a transient peaking factor the design flow climbs into the 75–150 m³/day band, where one or more 40' HC units — well within MENA-Water's 1200 m³/day per-container envelope — become the right fit. Pretreatment must be specified for hair, lint, and food solids, and an upstream EQ tank should be included. The table below summarizes both scenarios as a reference envelope only.

Both scenarios should be re-run with the AHJ's approved per-capita flow and peaking factor before the bid is issued; the values above are illustrative envelopes, not code-of-record numbers. For the underlying containerized MBR package plant hardware that the bid will reference, request the manufacturer's specific m³/day curve at the actual influent BOD/COD load rather than relying on a generic catalog number.

Procurement Checklist for an LA Containerized MBR Bid

Turn the engineering output into a list of items the buyer should request from each bidder so the bid responses can be compared on the same line items. The goal is a defensible specification, not a catalog re-quote.

• Confirm the manufacturer's m³/day rating at the actual influent BOD/COD, not at a generic benchmark — MENA-Water and HUBER Technology both note that plants are custom-fit to the application.
• Confirm container count and footprint against the LA site; ISO 20' and 40' HC footprints must fit the available pad and truck access for delivery and periodic submerged MBR membrane module replacement.
• Confirm electrical: Pure Aqua MBR-C ships 460V / 3Ph / 60Hz — match to the LA site service and standby power if needed.
• Confirm operating envelope: Pure Aqua MBR-C lists 68–86 °F (20–30 °C) operating and 68 °F (20 °C) design — relevant to LA summer heat, which can push aeration tank temperatures above the design band.
• Confirm the membrane cleaning regime: MENA-Water notes one or two maintenance clearings per year, with chemical cleaning only as required. Confirm local service and remote-monitoring support so cleaning cycles are not blocked by travel time.
• Confirm Title 22 and LACSD documentation in the bid package: effluent quality data, disinfection stage if required, and a statement of compliance with the AHJ's reuse tier.

For the underlying membrane module the bid will reference, a submerged MBR membrane module specified for the actual flow and BOD/COD load is the right procurement line item. For the engineering mechanics of the hollow-fiber module itself, this hollow fiber MBR engineering specs reference covers the selection logic behind that line item.

Frequently Asked Questions

What flow per person should I use to size a containerized MBR in Los Angeles?

Anchor the calculation on the 50 gallons per capita per day figure from the Pure Aqua MBR-C population table, then convert to metric at 0.189 m³ per person per day. The supplied research does not give a local LA per-capita override, so request the AHJ's approved per-capita and persons-per-household defaults before locking the design flow.

How do I pick between a 20' and a 40' HC container for an LA project?

Use the design flow after peaking, then match to the manufacturer's m³/day curve at the actual BOD/COD load. As a rule of thumb, sub-50 m³/day projects typically fit a single 20' HC ISO container; larger projects move to one or more 40' HC units, with MENA-Water's 1200 m³/day per-container envelope as the upper limit. Confirm the specific rating with the manufacturer for the actual influent strength.

What does a containerized MBR cost for a residential or camp project in LA?

The supplied research does not include CAPEX, OPEX, or delivery numbers for containerized MBR systems, so a defensible budget cannot be quoted here. The buyer should request an itemized bid from each manufacturer that breaks out container count, membrane module count, pretreatment, EQ tank, controls, and freight to the LA site, then compare the bids on the same line items.

What compliance documents should I require from a containerized MBR supplier for an LA installation?

Require a written statement of compliance with California Title 22 for the chosen reuse tier, the manufacturer's effluent quality data at the design BOD/COD load, and a list of permits the supplier has previously supported for LACSD or City of LA Bureau of Sanitation projects. Confirm that the bid package identifies the AHJ-specific permit pathway (LACSD Liquid Waste Management for unincorporated LA County; City of LA OWTS rules for in-city sites) so the supplier's compliance claim is matched to the actual reviewer's checklist.