By early 1849 a number of log cabins and frame buildings had risen on the waterfront. In mid-June 1849, Sacramento had 100 wood and canvas houses. Two months later in August it was reported that the city had upwards of 1000 houses.
On September 1, 1849, the French consul at Monterey wrote that he had been to Sacramento the previous season and that there was not a house or even a tent there. That only a few schooners lay in the port and that the only business of any importance was a trade or barter carried on at the fort of New Helvetia. Now that there is a town of 3000 to 4000 inhabitants, a quay lined with fine buildings, streets laid out and a large amount of business being conducted. Thirty-five ships lay at anchor, the smallest being fifty to sixty tons.
The town grew so rapidly that by October 1849, according to another report, it rose to over 6,000 people all crowded into 45 wooden buildings and 300 canvas houses.
Note that the figure of 45 buildings and 300 canvas houses for October 1849 contradict the "upwards of 1,000 houses" reported for August 1849. Somebody was wrong but there was no doubt that Sacramento was on the rise. As to the city's population for 1849, one source estimated it to be 12,000, but others put it in 1850 as 2-3,000, and 6,000, and 9,000. Could it have fluctuated that much? Perhaps so, another source reported that each hot flash of a new strike triggered an exodus from Sacramento, empting half the town, which then began to fill up with new arrivals.
River traffic also was escalating. One day in 1850 someone counted 65 steam and sailing vessels ranged along the waterfront.
1850 was notable because Sacramento became one of California's original counties. The census for that year placed Sacramento at 6,820.
California population was increasing so fast that the legislature ordered a special census in 1852. Sacramento County was listed at 12,589, including 9457 white males, 1739 white women, 804 Chinese of which 10 were females, and 80 domesticated Indians.
During the 1850's Sacramento experienced several fires and floods that leveled the city. In 1854 the State Capitol was permanently established in Sacramento. In 1854-56 the Sacramento Valley Railroad was built between Sacramento and Folsom, the first rail line west of the Mississippi River.
In 1860 the census placed Sacramento City's population at 13,785, an increase of 103%. This population increase is the biggest percentage of increase that Sacramento has ever experienced over a census period. Today (2013) the city of Sacramento is estimated to have 480,000 residents.
Brother Fred "Mr Magoo" Willcox