| Class | Monthly property rental. Pesos. | Liters of water allowed. | Price for 1,000 liters. Cents. | Minimum monthly rate. Pesos. | Rate for drainage service. Pesos. | Total rate payable. Pesos. | |
| I | Up to 20 | 7,800 | 16 | 1.25 | 1.09 | 2.25 | |
| II | 21 to 40 | 12,500 | 16 | 2.00 | 1.60 | 3.60 | |
| III | 41 to 60 | 18,750 | 16 | 3.00 | 2.40 | 5.40 | |
| IV | 61 to 120 | 23,350 | 15 | 3.50 | 2.80 | 6.30 | |
| V | 121 to 300 | 30,000 | 15 | 4.50 | 3.60 | 8.10 | |
| VI | 301 upward | 33,350 | 15 | 5.00 | 4.00 | 9.00 |
"Notes: (1st) The rental for the water meters 5⁄8-in. size (151⁄2 mm.), which shall always be considered the property of the Company, will be 20 cents per month. Houses of the first and second classes shall be exempt from paying such rental for one year's time, counting from this date.
"(2d) All excess consumption of water over that allowed by the tariff will be charged for at 2 cents less than the price shown in the tariff per thousand liters.
"(3d) Extra large houses, large establishments, such as colleges, hotels, etc., etc., having a consumption of 50,000 to 60,000 liters of water per month, will pay at the rate of 14 cents per thousand liters. The drainage rate for such buildings will be arranged in proportion to the water tariff, or 80% of the value of the water.
"(4th) The laundry establishments, bath-houses, etc., when using 50,000 liters or upward, can arrive at some agreement so as to pay 12 cents per 1,000 liters.
"(5th) Groups can be formed of two or more small houses so as to obtain a joint service under the proportion shown in the tariff.
"(6th) Any other combination that cannot be entered into under the basis of this tariff, will be arranged by specially agreed upon prices, such agreement being as much as possible subject to the basis mentioned."
Sanitary Regulations.—The State Government, on March 1st, 1909, published regulations for the proper installation of the water and drainage services within the houses.
At the Government's request, a draft of the proposed regulations was submitted by the writer, who prepared it, after a study of American
and British sanitary by-laws, to suit the special conditions of Monterrey. These regulations were afterward modified by him in collaboration with the Government Technical Inspector and Financial Interventor, and, in their final form, though not as stringent as those adopted in many northern cities, are probably more complete than those in any other Mexican city. Under these regulations only registered plumbers can undertake plumbing installations, and they have to execute a bond to the satisfaction of the Alcalde Primero (City Mayor) for the sum of 2,000 pesos as a guaranty of responsibility. For defective workmanship or any infraction of the plumbing regulations, they are liable to heavy fines, and can be called on to make good all defects in workmanship, without extra charge to the owner of the property. The provisions of the regulations are carried out under the supervision of the Government Technical Inspector, the Company's obligations extending only to the sidewalk and to the meters placed within the houses.