# SAM #191BWC24C0008P00012

Award modification for South Bay wastewater treatment plant rehabilitation and expansion

**Buyer:** INTERNAT. BOUNDARY AND WATER COMM.
**Posted:** October 13, 2026
**Identifier:** 191BWC24C0008P00012
**NAICS:** 237110, 237990, 236210

The International Boundary and Water Commission’s South Bay plant award modification adds major rehabilitation and expansion work in San Ysidro, California.
- **Government buyer:** International Boundary and Water Commission: U.S.-Mexico (IBWC); the notice does not identify a more specific sub-agency or office.
- **Award scope:** Progressive design-build rehabilitation and expansion of the South Bay International Wastewater Treatment Plant.
- **Added work and values:** Early Work Package 1C replacement-in-kind work ($13,147,453); Early Work Package 3B long-lead equipment procurement ($25,693,528); Early Work Package 4 major concrete structures ($37,468,188); Phase 1 base construction expansion ($369,613,306); and increased construction allowances ($9,804,886).
- **Equipment requested:** Standby generators with associated switchgear, medium-voltage switchgear, positive-displacement blowers, submersible solids-handling pumps, dewatering centrifuges, stainless-steel slide gates, and stop logs. No quantities, part numbers, OEMs, or equipment vendors are identified.
- **Construction and rehabilitation:** Replace roofs, process equipment and piping, electrical equipment, odor-control media, doors, emergency showers, and eyewashes; construct headworks and pump station facilities, sedimentation tanks, odor-control systems, sludge thickening and storage, dewatering and lime-handling facilities, electrical buildings, piping, and supporting infrastructure; and rehabilitate existing tanks and silos.
- **Contract value:** The modification increases the contract by $445,922,475, bringing the revised total to $552,372,021.

### Description

<p>The purpose of this modification is to incorporate additional construction packages and Phase 1 expansion work into the progressive design-build contract. The modification adds the following construction packages:</p>

<p>Early Work Package (EWP) 1C &ndash; Replacement In Kind</p>

<p>Final Construction Price: <strong>$13,147,453</strong></p>

<p>Scope includes:</p>

<ul>
	<li>Removal and replacement of existing roofs.</li>
	<li>Replacement of process equipment and piping.</li>
	<li>Replacement of electrical equipment.</li>
	<li>Replacement of odor control media.</li>
	<li>Installation of new window sealants.</li>
	<li>Replacement of coiling doors.</li>
	<li>Replacement of emergency showers and eyewashes.</li>
	<li>Painting and coating of existing facilities.&nbsp;</li>
</ul>

<p>Early Work Package (EWP) 3B &ndash; Early Procurement</p>

<p>Final Construction Price: <strong>$25,693,528</strong></p>

<p>Scope includes procurement of critical long-lead equipment, including:</p>

<ul>
	<li>Standby generators and associated switchgear.</li>
	<li>Medium-voltage switchgear.</li>
	<li>Positive displacement blowers.</li>
	<li>Submersible solids-handling pumps.</li>
	<li>Dewatering centrifuges.</li>
	<li>Stainless steel slide gates.</li>
	<li>Stop logs.&nbsp;</li>
</ul>

<p>Early Work Package (EWP) 4 &ndash; Major Concrete Structures</p>

<p>Final Construction Price: <strong>$37,468,188</strong></p>

<p>Scope includes:</p>

<ul>
	<li>Construction of major concrete structures for new Headworks facilities.</li>
	<li>Primary Sedimentation Tanks 6 and 7.</li>
	<li>Storage Warehouse.</li>
	<li>New influent and drainage infrastructure.</li>
	<li>Associated piping, carpentry, architectural, mechanical, electrical, and support features.&nbsp;</li>
</ul>

<p>Phase 1 Base Construction Expansion</p>

<p>Final Construction Price: <strong>$369,613,306</strong></p>

<p>Scope includes:</p>

<ul>
	<li>New Headworks facility with integrated pump station.</li>
	<li>Screening and grit removal systems.</li>
	<li>Primary sedimentation expansion.</li>
	<li>Centralized odor control facilities.</li>
	<li>Waste activated sludge thickening and storage facilities.</li>
	<li>Dewatering upgrades.</li>
	<li>Lime storage/feed and truck loadout facilities.</li>
	<li>Storage warehouse.</li>
	<li>Chlorination storage facility.</li>
	<li>Administrative building expansion.</li>
	<li>Multiple electrical buildings.</li>
	<li>New electrical service, generators, utility distribution systems, process piping, and site work.</li>
	<li>Rehabilitation of existing activated sludge tanks and lime silos.</li>
	<li>Engineering services during construction and procurement of the effluent meter and bypass piping.&nbsp;</li>
</ul>

<p>Construction Allowances</p>

<p>The contract also increases CLIN 008 Construction Allowances by <strong>$9,804,886</strong>, increasing the allowance amount from <strong>$1,783,374</strong> to <strong>$11,588,260</strong> to address uncertain construction elements and field conditions associated with EWP-1C and Phase 1 construction activities. [191BWC24C0008 P00012 | PDF]</p>

<p>Period of Performance</p>

<p>The base construction period of performance has been revised to <strong>1,643 calendar days (54 months)</strong> from issuance of the Base Construction Notice to Proceed (NTP). Construction closeout requirements remain unchanged and must be completed within 180 calendar days following construction completion.&nbsp;</p>

<p>Award Value</p>

<ul>
	<li>Previous Contract Value: <strong>$106,449,546</strong></li>
	<li>Modification Increase: <strong>$445,922,475</strong></li>
	<li>Revised Total Contract Value: <strong>$552,372,021</strong>&nbsp;</li>
</ul>

[View original listing](https://sam.gov/opp/fb3dc2bfe38f4cadad0b01ec41e87e68/view)