This circa 1877 map of Sacramento covers the city grid bounded by ‘B’ Street, 31st Street, ‘Y’ Street, and Front Street: constituting in effect present-day downtown and mid-town. It is essentially a plat map, probably produced by a city surveyor, outlining the city’s sewage system. The system features a varied infrastructure, as depicted on the map by means of color coding: Open Ditch (green), Wooden Sewer (yellow), Brick Sewer (red), Pipe Sewer (blue), and Proposed Sewer (dotted blue).
The 1870s saw an array of improvement projects designed to meet the demands of a Sacramento which was growing in population and remained a key hub of rail transport and trade. December 1861 and January 1862 had brought about devastating floods that placed the future of the city in doubt. In order to resolve the situation, the city residents agreed that additional levee construction was necessary. Earth was removed from a dangerous bend nearby the confluence of the two rivers and used to raise city blocks in 1868; the city’s sidewalks, until construction was finally finished, were uneven because neighbors of raised city blocks often remained at the pre-construction level.
After the filled regions beneath buildings had settled, new streets had to be paved. While planking had been used in the past, newly raised streets chose either the smooth Nicolson pavement or the easily dirtied (though durable) cobblestone pavement. Grading and paving processes were fully completed by 1873, leaving the first floors of many buildings at the time as basements and leaving second floors as new main floors. Proper sewage was an essential component of the new urban configuration. Today, this system of 19th-century basements is known as the Sacramento Underground.