Pure Water Rolls Dice with Sewage Spills

North City Project Pure Water San Diego Program

Commentary Louis Rodolico

The North City Project Pure Water San Diego Program EIR (Environmental Impact Report) is a raw sewage transport proposal. According to city officials the two proposed mains are 48 and 30 inches in diameter. These are not zero psi gravity sewers like 99% of the city’s sewers, but raw sewage that is being pumped under high pressure. The 48 inch forcemain will pump untreated sewage; 400 feet uphill, at 260 psi, from the Morena pump station to the North City Water Reclamation Plant 10 ½ miles away, see red line on the map. A 30 inch main returns to Morena with a more concentrated sludge, also red line on map. All pdf references are to the Project Proposal pdf link at the end of this article.

I have recently toured both the North City Water Reclamation Plant (NCWRP) or Pure Water Facility and the Miramar Sewage Treatment Plant known as the Metro Biosolids Center. Both are impressive with state of the art technologies in place. The future belongs to these technologies, but we should demand that the risks they pose be fully mitigated.

University, Clairemont & Morena recently experienced major pressurized pipe failures which ejected several million gallons of drinking water, which eventually drained into our canyons, bays and ocean. What if this were raw sewage spewing from a four foot diameter high pressure main? The ejection of raw sewage into the environment will do allot of damage, especially to those who are immunocompromised. Transporting liquid sewage at high pressure is risky and should be off limits to residential neighborhoods and watersheds. Underground steel pipes are subject to corrosion and shifts in the earth that damage and separate pipes. Therefore, we need to fully mitigate high pressure, toxic sewage.

Mitigation gets glancing consideration on Pdf page 1316  “North City Water Reclamation Plant, North City Pure Water Facility Influent Pump Station, and North City Renewable Energy Facility Various chemical, sewage, and recycled water spills have occurred at the NCWRP site; however, all have been contained and managed appropriately. Therefore, the risk of encountering a hazardous materials site is considered low.” I’m sorry, but this should not be a qualitative statement, but a quantitative statement with statistical information.

Mitigation is possible if the high pressure mains are in an underground service tunnel so when pipes rupture there will be enough volumetric capacity in the service tunnels to absorb the sewage and prevent it from getting into the environment. The spilled sewage will then drain into the existing gravity sewage system. This will be expensive, but it is the price we must pay if we are going to pump billions of gallons of raw sewage uphill through residential neighborhoods.

Also, why are we directing all sewage down to Morena, can we not intercept sewage at higher elevations which would drop service pressures and thereby risk? If high pressure sewage mitigation is cost prohibitive should we reconsider relocating the sewage treatment facilities near the Morena pump station so these high pressure uphill sewage lines are eliminated?

The University Planning Group UCPG is mobilizing against a forcemain in University. The Clairemont Planning Group CCPG held two votes with mixed results. CCPG did not seem to have the stomach to fight the city on this one. UCPG might accept the line turning east on 52 and then head north up 805 to the Pure Water Facility. Another alternate is to place the mains along the Interstates, see blue line on the map.

If the city considers the cost of disruption, then something like a deep tunnel with an aqueduct from Morena to the NCWRP, with a siphon well at the Pure Water Facility, may be the most economical method. San Diego does not provide Disruption or Public Safety Reports, and does not budget for these since it is not their cost; this is the definition of poor governance. We saw poor city governance with the Regents Road Bridge where community safety issues were not only ignored, but the city put a muzzle on public safety officials.

San Diego is doing an excellent job acquiring water for the future. The single forcemain Morena pump, with buried lines, in residential neighborhoods, is the most economical but riskiest of alternatives. According to managers Pure Water will become competitive with other water sources in about 10 years. But if they fully mitigate this proposed high pressure sewer line it could be longer than 10 years. Pdf page 1301;  “The North City Project has been designed to meet the City of San Diego’s development regulations to the extent feasible; however, due to Government Code Section 53091(e) the North City Project is not required to meet all standards (see Section 6.1, Land Use). Nonetheless, in all cases related to safety, the North City Project has been designed to meet the standards of applicable development regulations.”  In my opinion  “to the extent feasible” is the matter at hand. It is feasible to mitigate citizen safety and disruption during construction.

I for one support the Pure Water project, but the current alternative of a high pressure, sewer main through residential neighborhoods needs to be scrapped.

Centrifuges are one of the more interesting water purification technologies. Basically they spin sewer water at high speed. Inside there is a precision turbine like bladed shaft which separates out suspended solids. These centrifuges are made by overseas companies and cost a million dollars each. Europe is ahead of the US with this technology but they do manufacture some of their products here. America could miss out on upcoming technologies associated with global warming given the Federal position on climate change.

If you want your comments on the record, please send them by November 21, 2017 to the following address: Mark Brunette, Senior Environmental Planner, City of San Diego Development Services Center, 1222 First Avenue, MS 501, San Diego, CA 92101 or e-mail to; DSDEAS@sandiego.gov with Pure Water San Diego North City Project Draft Environmental Impact Report in the subject line.

Louis Rodolico has been a University resident since 2001                                                                                                                louisrodolico.com

Link: North City Project Proposal