Landfill & Sewage Plant Tour

This past Saturday morning until noon, my friend Michael and I, along with about 100 others of all walks, participated in a public tour led by the Los Angeles Department of Sanitation at Puente Hills Landfill and San José Creek Water Reclamation Plant.

People in a long line getting ready for tour.

I was very excited to attend this tour because, five years ago, I worked with Los Angeles Department of Public Works (LADPW) on a publication called the Countywide Siting Element, an integrated waste management plan for the County for the 10.16 million residents. The document made it clear that the County was running out of local landfill space. That time has now arrived. It had all been in the abstract until now.

The Landfill Tour

Puente Hills Landfill, the largest in the USA at 600 acres across and up to 500 feet deep, is now closed and no longer receiving dumps. The trash items are encased in a concrete-lined basin and buried at least five feet deep in soil. No water penetrates it. You can see a tree-studded mountain off of the 60-freeway.

It looks very natural but as you get closer, you see that the trees are all non-native: figs, eucalyptus, myrtles, with pipes, full of liquid leakage or methane emissions from the trash, weaving among the tree trunks. You can also see croppings of mysterious tanks and pumps throughout the mountainside. Nonetheless, there are plans to transform it into a public park.

Row of heavy duty tanks surrounded by trees and foliage.

The methane leads to a furnace where it is burned and the heat is used to create electricity. Water is used to cool down the air from the energy conversion and the vapor is released through these stacks.

Large industrial towers releasing vapor into the air.

At the foot of the mountain is a giant warehouse, the size of which I’ve never seen such so large in my life. The big trash trucks departing from them, after unloading, look like tiny dots.

Nearly aerial view of a humongous boxy warehouse-like plant at the foot of Puente Hills.

Inside, each truck must pay depending on what it is dropping off and how much. The types of trash are sorted into much more specific categories than just “recycling.” For example: wood, concrete, produce, paper, glass, etc.

Sorted trash in giant piles and bins inside the building.

After sorting and breaking down the categories of trash, they are either sold or transported by truck or train to distant processing sites.

The Sewage Tour

San José Creek water reclamation services existed before Puente Hills Landfill became a thing. It is the oldest sewage processing plant in LA County and a large one too. Check out these buttons. They don’t make them like this anymore!


It is the oldest sewage processing plant in LA County and a large one too. Today, the largest one is in Carson, the Joint Water Pollution Control Plant.

San José Creek Plant alone process some 100 million gallons per day. Sometimes, more sewage arrives than can be processed, particularly during storms. In such cases, the raw sewage goes straight into the ocean. A new plan, the Clearwater Project, will have large pipes built and installed into the Pacific, sending sewage a few miles out before it is released into the ocean, so it is away from the coast.

While this preserves the quality of water along the beaches and coastal properties, it does also send a bit of the wrong message: Out of sight, out of mind. Raw sewage is gross.


Our guide and Sanitation employee told us about the three stages of sewage processing.

Illustrated graphic of sewage processing.
  1. Primary – In tanks, beneath closed metal doors. Our guide opened some for us to see. It was too dark to see and the smell was too strong to approach.
  2. Secondary- The debris in the water is partially digested and the liquid is exposed to the air to enable further breakdown through natural processes. The odor is strong but less so.
  3. Tertiary – The water goes through intense sediment filtration and becomes clear.

Over 50% of LA’s water is from Sacramento and from the Colorado River. With those sources reducing their exports to LA, we need to curb water waste and, when it does rain, let rainfall recharge our groundwater sources. This means letting it drain into the soil rather than running off into the ocean.

As we face a city and world that is stretched thin for resources and changing as a result human impacts, what struck me the most during the tours was how much fuel and energy we are expending to manage waste. A toilet flushed in Pasadena must travel through a network of pipes to reach Whittier to be processed. Trash collected from a residential bin from Monrovia travels 30 miles in a heavy diesel truck to be sorted and then put on a diesel train to be hauled to Mesquite Canyon Landfill in the Mojave Desert. We are compounding our waste.

Some ways to conserve resources would be:
1. Worm-composting kitchen scraps. You can use the resulting fertilizer for your vegetable garden too.
2. Installing rain catchment bins and cisterns around buildings.
3. Building bioswales into garden landscapes. Grow native plants.
4. Recycling clean recyclable materials.
5. Buy only what you need and making it last.
6. Avoid single-use items.
7. Dispose of chemicals and toxic materials responsibly.

Leave a comment

Your email address will not be published. Required fields are marked *