The project involves:

• screening,
• grit removal,
• grease traps,
• primary lamella plate settlement and sludge removal,
• trickling filters,
• secondary lamella plate settlement and sludge removal,
• sludge treatment through anaerobic sludge digestion and mixing, with gas removal and flare off,
• sludge dewatering is by filter belt press. The project includes the construction of a protective dyke around the perimeter of the site to guard against floods during periods of heavy rain.

An air conditioned administration building will also be built, and operator training will be included during commissioning. Flow from the new collector system, installed throughout ManaguaCity, arrives by gravity and pump assistance at the new pump station, and is raised by this pump station to the inlet of the new works.

The plant is also equipped with a septage receiving station, which receives residue from septic tanks. The residue is delivered to the plant by tanker. The septage is received and runs by gravity to the inlet pump station where it is pumped to the inlet of the works.

Thickened sludge from the sludge thickeners is pumped to four unheated, fixed roof, mechanically stirred digesters.

The thickened sludge stays in the digesters for 20 days and the methane produced is flared off. The digested sludge is transferred to the sludge processing area by pumps, where it is dosed with polymer and fed through two belt presses to reduce it to sludge with a solid content of between 20% and 25%. The pressed sludge is then transferred off site for agricultural use. The plant is powered by electricity from the National Grid, via two transformers and two motor control centres, (one located in the control building and the other in the workshop/store). Should a mains power failure occur, two standby generators start to maintain operation of the plant automatically.

Main Items of Plant:

Intake Works:

• Automatic 6mm vertical bar screens - three duty, one standby, plus one standby 25mm screen manually raked, with a Grit Removal Rectangular Channels:
• Three channels 24 meters long with a bottom scraper and pumped grit removal. Maximum flow per channel 1,188 l/s.

Primary Settlement Tanks:

• Lamella plates - nine 22 meter long, seven meters wide, with reciprocating scrapers in each tank, each with a maximum flow of 396 l/s.

Intermediate Stage Pumping Station:

• Three variable speed canister pumps, (one duty, one assist, one standby) maximum flow rate per pump 1736 l/s.

Trickling Filters:

• Plastic media: six filters 35 meters diameter, 5.1 meter high. One rotating arm distributor per filter. Final Settlement Tanks: 
• Lamella plates - eight 22 meters long, 9.6 meters wide, with reciprocating scrapers in each tank, each with a maximum flow of 430 l/s

Final Effluent Pumping Station:

• Three fixed speed pumps (one duty, one assist, one standby), maximum flow rate per pump 1,720 l/s.

Two Gravity Thickeners:

• 20m diameter with rotating two arms scraper.

Sludge Digesters:

• Four fixed roof digesters each with three internal mixers. The surplus gas is sent to disposal through one flare off burner. The digested sludge is dewatered in two belt presses.
• The sludge is dried to approximately 25% solids and is suitable for use in agriculture.